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🚗 | You can test drive the popular electric kickboard and 3-wheel EV ... Asomobi 2021


Photo Asomobi 2021: Two-wheeled and three-wheeled motorcycles are also EV

You can test drive the popular electric kickboard and 3-wheel EV ... Asomobi 2021

 
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It also has a regenerative braking function, but it is said that mechanical disc brakes (all wheels) and drum brakes (rear wheels) are installed because regenerative braking is not recognized as the main braking device under domestic law.
 

Since "Mobi" in "Asomobi 2021" means mobility, the exhibition vehicle is not limited to four wheels. Exhibition of 4 and 2 wheels ... → Continue reading

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Drum brake

Drum brake(British: drum brake) Is a cylindrical member (drum) that rotates with the shaft.Brake shoePress (brake shoe) to obtain braking force and binding forcebrakeIs a kind of.

Overview

Drum brake methods can be broadly divided into pressing shoes on the outside of the drum.CircumscribedAnd press inwardInscribed, As well as both outside and insideInternal / external connection typeThere are three types.The circumscribed type is used for winches that wind up fishing nets and fishing nets for ships, and the inscribed type is used for wheels of automobiles and motorcycles.One end of the brake shoe is rotatably held as a swing shaft, and a load is applied to the other end via a hydraulic pressure, a cam, or a link mechanism, and the brake shoe is pressed against the drum.The side fixed to the swing shaft of the shoeHeel(British: very), The side to which the load is applied by flood controltoe (British: toe).When the sliding surface of the drum rotates in the direction from the toe to the heel, the frictional force applied to the shoe acts as a couple acting in the direction of pressing the shoe.As a result, a normal force greater than the load that operates the brake is applied, and a higher frictional force is generated.This is called self-boosting action.On the other hand, when it rotates in the opposite direction, a couple acting in the direction of releasing the shoe is generated, and the frictional force becomes weak.The disk is sandwiched from the side by the self-boosting action.Disc brakeCompared to a brake that sandwiches the wheel from the side, a high braking force and binding force can be generated with a low operating force.

Use in vehicles

The inscribed drum brake is one of the widely used brakes for braking the wheels of transportation machines traveling on land such as automobiles and motorcycles.Railway car,TramThere is also an example of adoption.Disc brakes are also widely used for automobiles, but they are smaller and lighter than disc brakes, have lower manufacturing costs, have self-boosting action, and have high binding force.[1][2]..On the other hand, inside the brake drumWedThere are drawbacks such as the braking force is reduced when a minute is entered, the recovery until it dries is slow, the heat dissipation is worse than the disc brake, and the controllability is low.[1][3]..Lightweight drums to improve heat dissipation (fade resistance) of drum brakesAluminumAlfin drum (made of) or equipped with heat dissipation fins in addition to itBritish: alfin brake drum) Etc. were adopted[4]..Abrasion resistance (life) by casting a steel cylinder on the inner sliding surface of the drum made by casting aluminum.Strength,rigidityThe structure that secures is adopted,Japanese carThen.1960 eraFor up tosports car,luxury carAdopted by[4].

Old timesPassenger carAnd smallfreight carHowever, it was common for vehicles to use drum brakes for all four wheels (all wheels), but with the improvement in power performance and the sophistication of user needs, disc brakes have been replaced, and many vehicle models have disc brakes on the front wheels. It came to be adopted.The last model of Japanese cars that adopted drum brakes on all four wheels (all wheels) except large cars was produced from January 4 to November 4 for ordinary cars.Nissan Bluebird(910 type systemBusiness carSeries only), mini vehicles produced from March 1996 to March 3Daihatsu Midget IIMet.Rear wheel brakes for inexpensive passenger cars and small freight carsParking brakeDrum brakes with high binding force are common because they also serve as.Also,Vehicle total weightBig oflarge OfTrack,busNow, the advantages of drum brakes are emphasized, and as of 2020SnowplowThe second generation that uses all-wheel (ventilated) disc brakes as standard on most vehicles except for a few special vehicles such asUD・QuonIt is used on all wheels except. For 4 wheelsDisc brakeAmong passenger cars that adopt the above, in the case of a relatively heavy vehicle, the parking brake by the disc brake is insufficient in binding force, so a mechanical drum brake dedicated to the parking brake is built in the rear wheel disc brake.Drum-in-disc typeOrInner drum typeIn some cases, a method called is adopted.Former medium-sized and heavy-duty trucksCross countryOf typeFour-wheel driveIn the carPropeller shaftA drum brake was placed in the parking brake.

Like passenger cars, motorcycles1970 eraUntil now, it was common to use mechanical drum brakes for both front and rear wheels, but front wheels have been replaced with hydraulic disc brakes in many vehicle models, and disc brakes have also been adopted for rear wheels in vehicles with high power performance. It became so.Drum brakes are left as they are mechanical, and many inexpensive and small models still use drum brakes for the front and rear wheels.

On the tram1950 eraFrom the late 1960sElastic wheelThere is an example of adoption in a high-performance vehicle manufactured by equipping with.Elastic wheels are for soundproofing and vibration isolationWheelA rubber cushioning material was incorporated between the wheel core and the tire of the tire, but in order to brake a vehicle with high power performance.Tread brakeWhen used continuously, there was a problem that the bolts that fasten the cushioning material loosened due to heat generation.In order to ensure high braking performance commensurate with high acceleration performance, a drum brake that does not transfer heat to the wheels was adopted instead of the tread brake.

There are two types of operation mechanism: one is to push one end of the shoe with a cam, and the other is to push it with a cylinder using hydraulic or pneumatic pressure.The operation mechanism using the cam operates the brake by pulling the end of the lever that rotates the shaft of the cam with a control cable.Widely used in automobile parking brakes and motorcycle brakes.In the operation mechanism using a cylinder, this cylinder is used.Wheel cylinderThe axial force of the piston is directly applied to one end of the shoe to operate it.The wheel cylinder is the base of the drum brakeBack plateIt may be fixed to, or it may be float-supported by one shoe.Often used in automobile foot brakes.

Subclassification

Rotation in the main direction of rotation causes the sliding surface to move from the toe to the heel, that is, the shoe is arranged to generate self-boosting action.Reading shoeAnd vice versaTrailing shoeCall[4]..In automobiles, the leading shoe is a shoe that produces a self-boosting effect when moving forward.It is classified as follows according to the arrangement of shoes and brake cylinders.

Reading trailing
The leading shoe and trailing shoe are opposed to each other, and it is the basic method of a drum brake that can operate with one mechanism to operate the shoe.[4]..This type is adopted for the rear wheels that also serve as parking brakes because the same braking force can be obtained for forward rotation (forward) and reverse rotation (reverse), the structure is simple, and the manufacturing cost is low.[4]..In addition to being used for the rear wheels of motorcycles, it is also used for the front wheels of small and inexpensive models.
Two reading
In the form of incorporating two leading shoes, the mechanism that operates the shoes is combined with one for each shoe.[5].. The two leading shoes provide a large braking force in forward rotation (forward), but the braking force is low in reverse rotation (backward) without self-boosting action.[5]..Used for front wheels that require a large braking force.Once a racing motorcycleSuzuki GT750,Suzuki TempterThe two-reading type was used symmetrically for the front wheels.Double panel to readingThe format called was adopted.
Uni Servo
It is a format that operates two-reading with one operation mechanism.[6].. The two shoes have their facing ends connected by a link mechanism, and the first leading shoe (Primary shoe) Is operated by the operating mechanism[6]..Meanwhile, the second shoe (Secondary shoeThe other end of) is rotatably supported and driven by the movement of the primary shoe transmitted through the link mechanism.[6].
Dual to reading
Two double-ended wheel cylinders are arranged as an operating mechanism, and each operates one end of the two shoes.[4]..Each shoe is pushed at both ends and acts as a two-leader for both forward and backward movements.[4]..Often used in the rear wheels of large vehicles in Japan[4].
Duo servo
An advanced version of touring, it is a method of operating two leading shoes with one movement mechanism.[4].. One end of the two shoes is connected to a common operating mechanism, and the other end is not fixed and the shoes are connected by a link mechanism.[4]..When the primary shoe operates by an operating mechanism such as a wheel cylinder and receives drum torque, it pushes the secondary shoe via the link mechanism.[5][4]..When reversing, the roles of the primary and secondary shoes are switched, and a strong braking force is exerted both during normal rotation (forward) and reverse (reverse).[4]..In addition to freight vehicles that require particularly large braking forcebusUsed for large passenger cars such as[5].

footnote

  1. ^ a b "JAF | Car Anything Question Box: Basic Knowledge of Mechanism | Difference between Disc Brake and Drum Brake”. Japan Automobile Federation. NovemberBrowse.
  2. ^ "What are the benefits of brake discs?What are the types of holes and their effects?”. I & C Cruise Co., Ltd. (June 2015, 6). As of September 16, 2015オ リ ジ ナ ル[Broken link]More archives.NovemberBrowse.
  3. ^ "| S & E Brake Co., Ltd.”. S & E Brake Co., Ltd. NovemberBrowse.
  4. ^ a b c d e f g h i j k l "Big Car Forest Automobile Information Encyclopedia" Sanei Shobo, 2003.ISBN 978-4-87904-678-9.
  5. ^ a b c d "Drum Brake | Automotive Brake | Product | Product / Technology | Akebono Brake Industry Co., Ltd.”. Akebono Brake Industry Co., Ltd. NovemberBrowse.
  6. ^ a b c "16 Standard Technology Collection Procedure 14-3-1 (PDF)". Patent Office.As of August 2015, 11オ リ ジ ナ ル[Broken link]More archives.NovemberBrowse.

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