1328545 九、發明說明： / 【發明所屬之技術領域】 本發明是有關於一種鼓式煞車機構，特別是有關於一 種可增進煞車制動效果之鼓式煞車機構。 【先前技術】 請參閱第1圖，一習知之鼓式煞車機構1主要包括有 B —煞車槓桿11、一煞車槓桿固定座12、一煞車導線21、 一導管22、一調整螺帽37、一煞車臂31、一固定盤33以 及一導線定位座33a。煞車槓桿11是以轉動之方式連接於 煞車槓桿固定座12，並且煞車槓桿11是與煞車導線21之 一端接合。煞車槓桿固定座12是設置於一機車之一把手 上。導管22之一端22a是固定於煞車槓桿固定座12，而 部份的煞車導線21是被導管22所包覆。煞車導線21之另 一端具有端部螺牙21a，端部螺牙21a是經由調整螺帽37 φ 來固定於煞車臂31上。導線定位座33a是設置於固定盤 33之上，而導管22之另一端22b是固定於導線定位座33a 上。 此外，如第1圖及第2圖所示，在固定盤33内設置有 一煞車凸輪34、一第一煞車蹄片35a、一第二煞車蹄片35b 以及一定位銷36。第一煞車蹄片35a是相對於第二煞車蹄 片35b，並且第一煞車蹄片35a之兩端及第二煞車蹄片35b 之兩端分別是抵接於煞車凸輪34及定位銷36。更詳細的 來說，第一煞車蹄片35a及第二煞車蹄片35b可以定位銷 0134-A22136TWF(N2)；A-503；hawdong 1328545 .36為旋轉支點來進行旋轉，因而可根據操作需要來抵緊摩 .、擦套設在固錢33相上之—輪框38, _可達成對輪 框38(或車輪)的煞車效果。此外，如第！圖及第2圖所示， 煞車臂31是連接於設置在固錢33内之煞車凸輪料。 ‘騎乘者欲對輪框38(或車輪)進行煞車操作時，騎 乘者可扳動煞車槓桿11來拉動煞車導線21，因而可使得 連接於煞車導線21之煞車臂31旋轉一角度。此時，連接 於煞車臂31之煞車凸輪34亦會隨之旋轉一角度，以使得 鲁第一煞車蹄片35a及第二煞車蹄片35b以定位銷36為旋轉 支點而撐開。在此，值得注意的是，當輪框38(或車輪)朝 車體刖方轉動（如第1圖及第2圖中之箭頭a所示方向轉動) 時，輪框38(或車輪)之煞車制動主要是靠第二煞車蹄片3讣 與其抵緊摩擦來達成。然而，由於第二煞車蹄片35b長時 間承受較大的煞車力作用，故其磨損速度會比第一煞車蹄 片35a來得快。如上所述，當第一煞車蹄片35a及第二煞 車蹄片35b之厚度不均勻時，整個鼓式煞車機構1之煞車 籲制動效果會變差。 有鑑於此，本發明之目的是要提供一種鼓式煞車機 構，其可使第一煞車蹄片及第二煞車蹄片受到均等之煞車 力作用，因而可使其磨損情形均勻化，進而提升整體煞車 制動效果。 【發明内容】 本發明基本上採用如下所詳述之特徵以為了要解決上 述之問題。也就是說，本發明包括一煞車槓桿固定座；一 0134-A22136TWF(N2)：A-503；hawdong 1328545 -··煞車槓桿，係以轉動之方式連接於該煞車槓桿固定座；一 / 輪框；一固定盤，套設於該輪框之中，並且具有一第一凸 輪、一第二凸輪、一第一煞車蹄片及一第二煞車蹄片’其 令’該第一煞車蹄片係相對於該第二煞車蹄片，該第一煞 車蹄片之兩端係分別抵接於該第一凸輪及該第二凸輪，以 及該第二煞車蹄片之兩端係分別抵接於該第一凸輪及該第 二凸輪；一第一煞車臂，係以轉動之方式設置於該固定盤 之上，並且係連接於該第一凸輪；一第二煞車臂’係以轉 ‘ 動之方式設置於該固定盤之上，並且係連接於該第二凸 輪；一導管，連接於該煞車槓桿固定座與該第二煞車臂之 間；以及一煞車導線，穿設於該導管之中，並且連接於該 煞車槓桿與該第一煞車臂之間，其中，當該煞車槓桿相對 於該煞車槓桿固定座轉動而拉動該煞車導線時’該煞車導 線係拉動該第一煞車臂以及該導管係推動該第二煞車臂， 以迫使該第一煞車臂及該第二煞車臂相向轉動，進而迫使 該第一凸輪及該第二凸輪轉動，以及該第一煞車蹄片及該 鲁第二煞車蹄片係藉由該第一凸輪及該第二凸輪之轉動而抵 緊摩擦該輪框。 同時，根據本發明之鼓式煞車機構’該第一凸輪具有 一第一圓弧部及一第一平面部，該第一圓弧部係相對且連 接於該第一平面部，該第二凸輪具有一第二圓弧部及一第 二平面部’該第二圓弧部係相對且連接於該第二平面部， 該第一煞車蹄片具有一第一圓弧凹槽及一第一抵擋平面， 該第二煞車蹄片具有一第二圓弧凹槽及一第二抵擋平面， 0134-Α22136TWF(N2) ： A-503；hawdon〇 8 1328545 -* 該第一圓弧部係以轉動之方式設置於該第一圓弧凹槽之 . 中，該第一平面部係抵接於該第二抵擋平面，該第二圓弧 部係以轉動之方式設置於該第二圓弧凹槽之中，該第二平 面部係抵接於該第一抵擋平面，以及當該第一凸輪及該第 二凸輪轉動時，該第一煞車蹄片係藉由該第二平面部之抵 推而抵緊摩擦該輪框以及該第二煞車蹄片係藉由該第一平 面部之抵推而抵緊摩擦該輪框。 又在本發明中，該煞車導線之長度係大於該導管之長 • 度，以及該煞車導線係經由該第二煞車臂而連接於該第一 煞車臂。 又在本發明中，更包括一定位座及一調整螺栓，其中， 該定位座係設置於該固定盤之上，以及該調整螺栓係鎖附 於該定位座，並且係抵接於該第二煞車臂，用以調整該第 二煞車臂之位置。 又在本發明中，更包括一第一回復彈簧及一第二回復 彈簧，其中，該第一回復彈簧係連接於該固定盤與該第一 • 煞車臂之間，以及該第二回復彈簧係連接於該固定盤與該 第二煞車臂之間。 又在本發明中，該固定盤更具有至少一拉伸彈簧，係 連接於該第一煞車蹄片與該第二煞車蹄片之間。 為使本發明之上述目的、特徵和優點能更明顯易懂， 下文特舉較佳實施例並配合所附圖式做詳細說明。 【實施方式】 茲配合圖式說明本發明之較佳實施例。 0134-A22136TWF(N2)；A-503；hawdong 9 1328545 • 請參閱第3圖，本實施例之鼓式煞車機構loo主要包 ·、括有一煞車槓桿固定座110、一煞車槓桿120、一輪框130、 一，定盤140、一第一煞車臂15〇、一第二煞車臂155、一 導官160、一煞車導線Π0、一定位座18〇、一調整螺栓185、 一第一回復彈簧190及一第二回復彈簧195。 煞車槓桿固定座110可以是設置於一機車之上，而煞 車槓桿120是以轉動之方式連接於煞車槓桿固定座11〇。 如第3圖、第4A圖、第4B圖及第4C圖所示，固定 •盤140是套設於輪框130之中，並且固定盤 -凸輪，一第二凸輪142、一第一煞車盤蹄片二有一 J 二煞車蹄片144及兩拉伸彈簧145。如第4八圖、第43圖 及第4C圖所示’第-煞車蹄片143相對於第二煞車蹄片 144。第-煞車蹄片143之兩端是分別抵接於第—凸輪i4i 及第二凸輪142,而第二煞車蹄片144之兩端亦是分別抵 接於第-凸輪141及第二凸輪142。更詳細的來說，第一 凸輪141具有-第-圓弧部141a及一第一平面部勵， 鲁第-圓弧部141a是相對且連接於第一平面部i4ib。第二 凸輪142具有-第二圓弧部142a及一第二平面部屬， 第二圓弧部142a是相對且連接於第二平面部14沘。如第 4C圖所示，第-煞車蹄片143具有一第一圓弧凹槽143& 及一第一抵擋平面143b，而第二煞車蹄片144具有一第二 圓弧凹槽144a及一第二抵擋平面144b。第一凸輪i4i之 第一圓弧部141a是以轉動之方式設置於第一煞車蹄片143 之第-圓弧凹槽143a之中’而其第一平面部襲則是抵 0134-A22136TWF(N2) ；A-503； hawdong 1328545 :外，煞車導線170具有一第一端171及一第二端π， ,舳I71疋固疋於煞車槓桿120之上，而第二端172成 形有螺紋，並且是藉由鎖附於一調整螺帽196而連接於第 一煞車臂150。 定位座180是設置於固定盤140之上。 η調整螺检185是鎖附於定位a 18〇,並且調整螺栓185 疋抵接於第二煞車f 155,其可用來調整第二煞車臂⑸ 之位置。 接下來說明鼓式煞車機構之運作方式。 當-操作者欲對輪框130(或車輪）進行煞車操作時，騎 者可扳動煞車槓桿12G，此時，煞車槓桿12G會相對於 煞車槓桿si定座no轉動而拉祕車導線17(^在此煞 車導線170會拉動第一煞車臂15〇以及導管16〇會推動第 二煞車臂155，以迫使第一煞車臂15〇及第二煞車臂155 相向轉動’進而迫使固錢14〇内之第—凸輪ΐ4ι及第二 凸輪142轉動。更詳細的來說，煞車導線17G會先拉動第 一煞車臂15〇，第-凸輪141之第一圓弧部_會在第一 煞車蹄片143之第一圓弧凹槽1433中轉動，而其第一平面 部141b會抵推第二煞車蹄片144之第二抵擋平面！州， 以將第二煞車蹄片144撐開（如第4B圖所示），因而使得第 二煞車蹄片144抵緊摩擦(依箭頭B所示之方向)轉動之輪 框130。在另一方面’導管16〇會接著推動第二煞車臂丨55, 第二凸輪142之第二圓弧部142a會在第二煞車蹄片144之 第二圓弧凹槽144a中轉動，而其第二平面部M2b會抵推 0134-A22136TWF(N2)；A-503；hawdong 12 1328545 、車蹄143之第一抵擋平面1431)，以將第一煞車蹄 ⑷撐開（如帛4c圖所示），因而使得第一煞車蹄片143 抵緊摩擦(依箭頭B所示之方向）轉動之輪框13〇。 如上所述，當輪框13〇(或車輪)朝車體前方轉動(如第3 ^、第4A圖、f 4B圖及第4C圖中之箭頭b所示方向轉 由於第一煞車蹄片143及第二煞車蹄片144被撐開 之方向是與輪框230(或車輪)之轉動方向相同（例如，在第1328545 IX. DESCRIPTION OF THE INVENTION: / TECHNICAL FIELD OF THE INVENTION The present invention relates to a drum brake mechanism, and more particularly to a drum brake mechanism that can improve the brake effect of a brake. [Prior Art] Referring to Figure 1, a conventional drum brake mechanism 1 mainly includes a B-brake lever 11, a brake lever mount 12, a brake wire 21, a conduit 22, an adjustment nut 37, and a The brake arm 31, a fixed disk 33 and a wire positioning seat 33a. The brake lever 11 is rotationally coupled to the brake lever mount 12, and the brake lever 11 is engaged with one end of the brake wire 21. The brake lever mount 12 is disposed on one of the handles of a locomotive. One end 22a of the duct 22 is fixed to the brake lever mount 12, and a part of the brake wire 21 is covered by the duct 22. The other end of the brake wire 21 has an end thread 21a, and the end thread 21a is fixed to the brake arm 31 via an adjusting nut 37φ. The wire positioning seat 33a is disposed above the fixed disk 33, and the other end 22b of the catheter 22 is fixed to the wire positioning seat 33a. Further, as shown in Figs. 1 and 2, a brake cam 34, a first brake shoe 35a, a second brake shoe 35b, and a positioning pin 36 are disposed in the fixed disk 33. The first brake shoe 35a is opposite to the second brake shoe 35b, and both ends of the first brake shoe 35a and the second brake shoe 35b are abutted against the brake cam 34 and the positioning pin 36, respectively. In more detail, the first brake shoe 35a and the second brake shoe 35b can be positioned by the pin 0334-A22136TWF (N2); A-503; hawdong 1328545.36 is rotated by the pivot point, so that it can be operated according to the operation needs. The wheel frame 38, _ can achieve the braking effect on the wheel frame 38 (or the wheel). Also, like the first! As shown in Fig. 2 and Fig. 2, the brake arm 31 is connected to a brake cam material provided in the solid money 33. ‘When the rider wants to perform a braking operation on the wheel frame 38 (or the wheel), the rider can pull the brake lever 11 to pull the brake wire 21, thereby rotating the brake arm 31 connected to the brake wire 21 by an angle. At this time, the brake cam 34 connected to the brake arm 31 is also rotated by an angle so that the first brake shoe 35a and the second brake shoe 35b are pivoted with the positioning pin 36 as a pivot point. Here, it is worth noting that when the wheel frame 38 (or the wheel) rotates toward the side of the vehicle body (rotating in the direction indicated by the arrow a in FIGS. 1 and 2), the wheel frame 38 (or the wheel) The brakes of the brakes are mainly achieved by the friction of the second brake shoe 3讣. However, since the second brake shoe 35b is subjected to a large braking force for a long period of time, the wear speed is faster than that of the first brake shoe 35a. As described above, when the thicknesses of the first weeping shoe 35a and the second weir shoe 35b are not uniform, the braking effect of the entire drum brake mechanism 1 is deteriorated. In view of the above, an object of the present invention is to provide a drum brake mechanism that can cause the first brake shoe and the second brake shoe to be subjected to equal braking force, thereby uniformizing the wear condition and thereby improving the overall situation. Brake braking effect. SUMMARY OF THE INVENTION The present invention basically employs the features detailed below in order to solve the above problems. That is, the present invention includes a brake lever mount; a 0314-A22136TWF (N2): A-503; hawdong 1328545 - a brake lever that is rotationally coupled to the brake lever mount; a / wheel frame a fixed disk disposed in the wheel frame and having a first cam, a second cam, a first brake shoe and a second brake shoe 'which makes the first brake shoe system The two ends of the first brake shoe are respectively abutted against the first cam and the second cam, and the two ends of the second brake shoe are respectively abutted against the second brake shoe a cam and the second cam; a first brake arm is disposed on the fixed plate in a rotating manner and is coupled to the first cam; and a second brake arm is disposed in a rotating manner Above the fixed disk, and connected to the second cam; a conduit connected between the brake lever mount and the second brake arm; and a brake wire disposed in the conduit and connected Between the brake lever and the first brake arm, wherein When the brake lever rotates relative to the brake lever mount to pull the brake wire, the brake wire pulls the first brake arm and the conduit pushes the second brake arm to force the first brake arm and the first brake arm The second arm rotates toward each other, thereby forcing the first cam and the second cam to rotate, and the first brake shoe and the second brake shoe are rotated by the rotation of the first cam and the second cam Tightly rub the wheel frame. Meanwhile, according to the drum brake mechanism of the present invention, the first cam has a first circular arc portion and a first planar portion, and the first circular arc portion is oppositely coupled to the first planar portion, the second cam The second circular arc portion has a second circular arc portion and is connected to the second planar portion, and the first brake shoe has a first circular arc groove and a first resisting portion Plane, the second brake shoe has a second arc groove and a second abutment plane, 0134-Α22136TWF(N2): A-503; hawdon〇8 1328545-* the first arc portion is rotated The method is disposed in the first circular arc groove. The first planar portion abuts against the second resisting plane, and the second circular arc portion is disposed in the second circular arc groove in a rotating manner. The second planar portion abuts against the first resisting plane, and when the first cam and the second cam rotate, the first brake shoe is resisted by the second planar portion Tightly rubbing the wheel frame and the second brake shoe is abutting against the wheel frame by the pushing of the first flat portionIn still another aspect of the invention, the length of the brake wire is greater than the length of the conduit, and the brake wire is coupled to the first brake arm via the second brake arm. In the present invention, the method further includes a positioning seat and an adjusting bolt, wherein the positioning seat is disposed on the fixing plate, and the adjusting bolt is locked to the positioning seat and is abutted against the second The brake arm is used to adjust the position of the second brake arm. In the present invention, the method further includes a first return spring and a second return spring, wherein the first return spring is coupled between the fixed disc and the first arm and the second return spring Connected between the fixed disk and the second brake arm. In still another aspect of the invention, the fixed disk further has at least one tension spring coupled between the first brake shoe and the second brake shoe. The above described objects, features and advantages of the present invention will become more apparent from the description of the appended claims. [Embodiment] A preferred embodiment of the present invention will be described with reference to the drawings. 0134-A22136TWF(N2); A-503; hawdong 9 1328545 • Please refer to FIG. 3, the drum brake mechanism loo of the present embodiment mainly includes a brake lever mount 110, a brake lever 120, and a wheel frame 130. First, the fixed plate 140, a first brake arm 15〇, a second brake arm 155, a guide 160, a brake wire Π0, a positioning seat 18〇, an adjusting bolt 185, a first return spring 190 and A second return spring 195. The brake lever mount 110 may be disposed on a locomotive, and the brake lever 120 is coupled to the brake lever mount 11 in a rotational manner. As shown in FIG. 3, FIG. 4A, FIG. 4B and FIG. 4C, the fixing plate 140 is sleeved in the wheel frame 130, and the fixed disk-cam, the second cam 142, and the first brake disk are fixed. The shoe piece 2 has a J two-turned shoe piece 144 and two tension springs 145. As shown in Figs. 4, 43 and 4C, the first-inch shoe piece 143 is opposite to the second side shoe piece 144. Both ends of the first weeping shoe 143 abut against the first cam i4i and the second cam 142, respectively, and the two ends of the second weir shoe 144 are respectively abutted against the first cam 141 and the second cam 142. More specifically, the first cam 141 has a --arc portion 141a and a first plane portion, and the Lu-Arc portion 141a is opposed to and connected to the first plane portion i4ib. The second cam 142 has a second circular arc portion 142a and a second planar portion, and the second circular arc portion 142a is opposite and connected to the second planar portion 14A. As shown in FIG. 4C, the first weir shoe piece 143 has a first circular arc groove 143& and a first resisting plane 143b, and the second rolling shoe piece 144 has a second circular arc groove 144a and a first The second resists the plane 144b. The first circular arc portion 141a of the first cam i4i is disposed in the first arc-shaped groove 143a of the first brake shoe 143 in a rotational manner, and the first planar portion thereof is offset to 0334-A22136TWF (N2) A-503; hawdong 1328545: outside, the brake wire 170 has a first end 171 and a second end π, the 舳I71 is fixed on the brake lever 120, and the second end 172 is formed with a thread, and It is connected to the first brake arm 150 by being attached to an adjustment nut 196. The positioning seat 180 is disposed on the fixed plate 140. The η adjustment screw 185 is locked to the position a 18 〇, and the adjustment bolt 185 疋 abuts against the second brake f 155, which can be used to adjust the position of the second brake arm (5). Next, the operation of the drum brake mechanism will be explained. When the operator wants to perform the braking operation on the wheel frame 130 (or the wheel), the rider can pull the brake lever 12G. At this time, the brake lever 12G will rotate relative to the brake lever si to pull the secret car wire 17 ( ^When the brake wire 170 pulls the first brake arm 15〇 and the conduit 16〇 pushes the second brake arm 155 to force the first brake arm 15〇 and the second brake arm 155 to rotate toward each other, thereby forcing the solid money within 14 inches. The first - the cam ΐ 4 ι and the second cam 142 rotate. In more detail, the brake wire 17G first pulls the first brake arm 15 〇, and the first circular arc portion _ of the first cam 141 will be in the first brake shoe 143 The first circular arc groove 1433 rotates, and the first flat portion 141b thereof pushes against the second resisting plane of the second brake shoe 144! to open the second brake shoe 144 (as shown in FIG. 4B) As shown, thereby causing the second shovel 144 to abut the wheel frame 130 that is rotated (in the direction indicated by arrow B). On the other hand, the 'duct 16 〇 will then push the second arm 丨 55, second The second circular arc portion 142a of the cam 142 is rotated in the second circular arc groove 144a of the second brake shoe piece 144. And the second planar portion M2b is pressed against 0334-A22136TWF (N2); A-503; hawdong 12 1328545, the first resisting plane 1431 of the hoof 143) to open the first shovel (4) (such as 帛 4c) As shown, the first brake shoe 143 is thereby abutted against the friction (in the direction indicated by arrow B). As described above, when the wheel frame 13 (or the wheel) is rotated toward the front of the vehicle body (for the directions indicated by the arrow b in the 3rd, 4th, 4th, and 4th, and the arrow b), the first brake shoe 143 is turned. And the direction in which the second brake shoe 144 is distracted is the same as the direction of rotation of the wheel frame 230 (or the wheel) (for example, in the first
从圖、$4B圖及帛4Cffi中皆為順時針方向），故產生之 ^車制動力會大幅增加。也就是說，鼓式煞車機構_之 整體煞車制動絲會A幅提升。此外，由- 143及第二。煞車蹄片144是受到均等之煞車力作用，故其 兩者之磨損情形會較為均勻，因而亦可提升鼓式煞車機構 100之整體煞車制動效果。 雖然本發明已以較佳實施例揭露於上，然其並非用以 限定本發明’任何熟習此項技藝者，在不脫離本發明之精 神和範圍内’當可作些許之更動與潤飾，因此本發明之保 護範圍當視後附之申請專利範圍所界定者為準。From the figure, $4B and 帛4Cffi are all clockwise), so the resulting car brake force will increase significantly. In other words, the overall brake brake wire of the drum brake mechanism will increase in A. In addition, by - 143 and second. The brake shoe 144 is subjected to equal braking force, so that the wear of the two shoes is relatively uniform, and thus the overall braking effect of the drum brake mechanism 100 can be improved. Although the present invention has been disclosed in its preferred embodiments, it is not intended to limit the invention, and the invention may be modified and modified without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.
0134-A22136TWF(N2)：A-503：hawdonQ 1328545 【圖式簡單說明】 第1圖係顯示一習知鼓式煞車機構之平面示意圖； 第2圖係顯示根據第1圖之習知鼓式煞車機構之固定 盤之内部構造示意圖； 第3圖係顯示本發明之鼓式煞車機構之平面示意圖； 第4A圖係顯示根據第3圖之鼓式煞車機構之固定盤之 一内部構造示意圖； 第4B圖係顯示根據第3圖之鼓式煞車機構之固定盤之 另一内部構造示意圖；以及 第4C圖係顯示根據第3圖之鼓式煞車機構之固定盤之 又一内部構造示意圖。 【主要元件符號說明】 I、 100〜鼓式煞車機構 II、 120〜煞車槓桿 12、110〜煞車槓桿固定座 21、 170〜煞車導線 21a〜端部螺牙 22、 160〜導管 22a、22b 〜端 31〜煞車臂 33、140〜固定盤 33a〜導線定位座 34〜煞車凸輪 0134-A22136TWF(N2) ；A-503； hawdong ί S ) 1328545 v 35a、143〜第一煞車蹄片 35b、144〜第二煞車蹄片 3 6〜定位銷 37、 196〜調整螺帽 38、 130〜輪框 141〜第一凸輪 141a〜第一圓弧部 141b〜第一平面部 • 142〜第二凸輪 142a〜第二圓弧部 142b〜第二平面部 143a〜第一圓弧凹槽 143b〜第一抵擋平面 144a〜第二圓弧凹槽 144b〜第二抵擋平面 145〜拉伸彈簧 • 150〜第一煞車臂 155〜第二煞車臂 171〜第一端 172〜第二端 180〜定位座 185〜調整螺栓 190〜第一回復彈簧 195〜第二回復彈簧 0134-A22136TWF(N2)；A-503；hawdon〇 150134-A22136TWF(N2): A-503:hawdonQ 1328545 [Simple description of the drawings] Fig. 1 is a schematic plan view showing a conventional drum brake mechanism; Fig. 2 is a schematic view showing a drum brake according to the first figure. Schematic diagram of the internal structure of the fixed disc of the mechanism; Fig. 3 is a plan view showing the drum brake mechanism of the present invention; Fig. 4A is a schematic view showing the internal structure of the fixed disc of the drum brake mechanism according to Fig. 3; The figure shows another internal configuration diagram of the fixed disk of the drum brake mechanism according to Fig. 3; and Fig. 4C shows another internal structure of the fixed disk of the drum brake mechanism according to Fig. 3. [Description of main component symbols] I, 100~Drum brake mechanism II, 120~ brake lever 12, 110~ brake lever mount 21, 170~ brake wire 21a~ end screw 22, 160~ conduit 22a, 22b~end 31~煞-arm 33,140~fixing plate 33a-wire positioning seat 34~ brake cam 0334-A22136TWF(N2); A-503; hawdong ί S) 1328545 v 35a, 143~ first brake shoe 35b, 144~ Two-way car shoes 3 6 to positioning pins 37, 196 to adjusting nuts 38, 130 to wheel frame 141 to first cam 141a to first arc portion 141b to first plane portion 142 to second cam 142a to second Arc portion 142b to second plane portion 143a to first arc groove 143b to first abutting plane 144a to second arcuate groove 144b to second abutting plane 145 to tension spring • 150 to first brake arm 155 ~ second brake arm 171 ~ first end 172 ~ second end 180 ~ positioning seat 185 ~ adjustment bolt 190 ~ first return spring 195 ~ second return spring 0334-A22136TWF (N2); A-503; hawdon 〇 15