201217667 六、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 種可有效提升煞車制動效果之鼓式煞車機構。 【先前技術】 請參閱第1A圖、第1B圖及第2圖，一習知之鼓式煞 車機構1主要包括有一固定盤10、一輪鼓20、一定位銷 30、一凸輪40、一煞車臂50、一煞車導線60、一第一煞 車蹄片71、一第二煞車蹄片72及兩拉伸彈簧80。 輪鼓20是以轉動之方式套設於固定盤10之中。在此， 輪鼓20乃是一車輪輪框（未顯示）之一部份。 定位銷30是連接於固定盤10，並且定位銷30是被輪 鼓20圍繞。 如第2圖所示，凸輪40是以轉動之方式套設於固定盤 10之中，並且凸輪40亦是被輪鼓20圍繞。 煞車臂50是連接於凸輪40，其可用來驅使凸輪40轉 動。 如第1A圖、第1B圖及第2圖所示，煞車導線60是 連接於煞車臂50，其可用來驅使煞車臂50轉動。 第一煞車蹄片71及第二煞車蹄片72是以彼此相對之 方式設置於輪鼓20之中。在此，第一煞車蹄片71之兩端 及第二煞車蹄片72之兩端是分別抵接於凸輪40及定位銷 30，以及第一煞車蹄片71及第二煞車蹄片72皆是以可分 離之方式抵緊摩擦輪鼓20。 201217667 兩拉伸彈簀80是連接於第一煞車蹄片71與第二煞車 蹄片72之間，其可使得第一煞車蹄片71之兩端及第二煞 車蹄片72之兩端分別保持抵接於凸輪40及定位銷30。 當一操作者欲對輪鼓20 (或車輪輪框）進行煞車操作 時，操作者可藉由一煞車操作裝置（未顯示）來拉動煞車導 線60，因而可使得連接於煞車導線60之煞車臂50旋轉一 角度，如第1B圖所示。此時，連接於煞車臂50之凸輪40 亦會隨之旋轉一角度，以使得第一煞車蹄片71及第二煞車 φ 蹄片72以定位銷30為旋轉支點而撐開。在此，當第一煞 車蹄片71及第二煞車蹄片72被凸輪40撐開時，由於構造 上的限制，第一煞車蹄片71會比第二煞車蹄片72優先接 觸到輪鼓20。由於凸輪40只能在固定盤10上進行旋轉運 動，而無法進行位移運動，故第二煞車蹄片72便無法完全 與輪鼓20接觸，因而使得第二煞車蹄片72與輪鼓20之間 的摩擦面積不足，進而導致鼓式煞車機構1之煞車制動效 果不佳。 • 有鑑於此，本發明之目的是要提供一種鼓式煞車機 構，其可使得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，本發明包括一固定盤；一輪鼓，係 以轉動之方式套設於該固定盤之中；一定位銷，連接於該 201217667 [ ===:^?固定盤之中;-襯套，套設於 襯套之該輛向偏心孔”二輪/套設於該 :偏::之中，並且抵緊於該襯套與該凸輪::套二： =鼓:Γ該輪鼓之中;以及一第二煞車蹄片，設置： 敏車蹄片之/且相對於該第—煞車蹄片，其t，該第- 凸第4車蹄片之兩端係分別抵接於該 輪及該疋位銷’以及該第一煞車蹄片 係以可分離之方式把緊摩擦該輪鼓。 ‘，，、旱蹄片 巧’根據本發明之鼓式煞車機構，其更包括至少一 間1隹黃’係連接於該第一煞車蹄片與該第二煞車蹄片之 /又在本發明t，該鼓式煞車機構更包括—煞車導線， 係連接於該煞車臂，用以驅使該煞車臂轉動。 為使本發明之上述目的、特徵和優點能更明顯易僅， 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】 鲁 知配合圖式說明本發明之較佳實施例。 請參閱第3圖、第4圖及第5圖，本實施例之鼓式煞 車機構100可以是適用於一機車之中’並且其主要包括 一固定盤110、一輪鼓120、一定位銷130、一軸承14〇、 一襯套150、一凸輪160、一油封17〇、一煞車臂18〇、— 煞車導線185、一第一煞車蹄片191、一第二煞車蹄片 6 201217667 及兩拉伸彈簧195。 輪鼓120是以轉動之方式套設於固定盤110之中。在 此，輪鼓120乃是一車輪輪框（未顯示）之一部份。 定位銷130是連接於固定盤110，並且定位銷130亦 是被輪鼓120圍繞。 軸承140是設置於固定盤110之中，並且轴承140亦 是被輪鼓120圍繞。 如第4圖所示，襯套150是套設於軸承140之中，並 φ 且襯套15〇具有一軸向偏心孔151。 凸輪160是套設於襯套150之軸向偏心孔151之中。 油封170是設置於襯套150之軸向偏心孔151之中， 並且油封170是抵緊於襯套150與凸輪160之間。 如第3圖、第4圖及第5圖所示，煞車臂180是連接 於凸輪160，其可用來驅使凸輪160轉動。 煞車導線185是連接於煞車臂180，其可用來驅使煞 車臂180轉動。 • 如第3圖所示，第一煞車蹄片191及第二煞車蹄片192 是以彼此相對之方式設置於輪鼓120之中。在此，第一煞 車蹄片191之兩端及第二煞車蹄片192之兩端是分別抵接 於凸輪160及定位銷130,以及第一煞車蹄片191及第二 煞車蹄片192皆是以可分離之方式抵緊摩擦輪鼓120。 兩拉伸彈簧195是連接於第一煞車蹄片191與第二煞 車蹄片192之間，其可使得第一煞車蹄片191之兩端及第 二煞車蹄片192之兩端分別保持抵接於凸輪160及定位銷 130 ° 201217667 田操作者奴對輪鼓120 (或車輪輪框）進行煞車操作 時，操作者可動1車㈣裝置（未㈣）來拉動煞車導 線185 ’ 而可使得連接於煞車導'線185之煞車臂⑽旋 轉角度如第6A圖及第6B圖所示。此時，連接於煞車 臂180之凸輪160亦會隨之旋轉一角度。在此，值得注意 的疋’由於油封170是抵緊於襯套15〇與凸輪16〇之間， 故凸輪160與襯套15〇之間會有一阻抗存在。在另一方面， 由於襯套150是套設於軸承14〇之中，故概套15〇可以相 對於固定盤11G自由轉動。如上所述，當煞車臂18〇帶動 凸輪160旋轉時，襯套15〇會與凸輪16〇同步旋轉，並且 凸輪16G會將第-煞車蹄片191及第二煞車蹄片μ撐 開。接著，當第一煞車蹄片〗91優先接觸到輪鼓12〇時， 如第6B圖所示，凸輪16〇仍會繼續被煞車臂18〇帶動。此 時’由於輪鼓120(或第一煞車蹄片191)會對凸輪16〇施加 (向下之）反作用力，故凸輪16〇與襯套15〇會開始產生 相對旋轉運動。更具體而言，概套15〇會(朝逆時針方向） 轉動以及套設於襯套15G之軸向偏心孔151中之凸輪16〇 會同時產生(順時針)旋轉及（向下)位移，㈣可以迫使第二 煞車蹄片192與輪鼓120發生確實的接觸，進而能增加第 二煞車蹄片192與輪鼓12G摩擦接觸的面積，如第6c圖所 不。如上所述，在本實施例所揭露之鼓式煞車機構議之 運作下’第-煞車蹄片191及第二煞車蹄片192會受到均 等之煞車力作用，因而可使其磨損情形均勻化，進而可提 升整體煞車制動效果。 此外’如第6D圖所示’當煞車導線185不再拉動煞 201217667 車臂180時，兩拉伸彈簧195會迫使第一煞車蹄片191及 第二煞車蹄片192與輪鼓120分離，以解除煞車狀態。此 時，凸輪160與襯套150又會產生相對旋轉運動，而回復 至其原始位置處，如第6A圖所示。 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。 201217667 【圖式簡單說明】 一第1A圖係顯示一種習知之鼓式煞車機構於一種 狀恶下之平面示意圖； 圖係顯示習知之鼓式煞車機構於另—種運作狀 L卜之平面示意圖； 第2圖係顯示根據第1A圖之A-A剖面示意圖； =圖係顯示本發明之鼓式煞車機構之平面示意圖； 圖係顯示根據第3圖之B-B剖面示意圖； 圖；5 本發明之鼓式煞車機構之部份平面示意 態下本發明之鼓式煞車機構於-種運作狀 狀態㈣之鼓式煞車機構於另—種運作 狀態下之平面示’意:本::之鼓式煞車機構於再-種運作 狀態本㈣之鼓心車機構於又-種運作 【主要元件符號說明】 1、100〜鼓式煞車機構 10、〗10〜固定盤 2() ' 120〜輪鼓 、130〜定位錦 40、】60〜凸輪 201217667 50、180〜煞車臂 60、185〜煞車導線 71、 191〜第一煞車蹄片 72、 192〜第二煞車蹄片 80、195〜拉伸彈簧 140〜轴承 150〜襯套 151〜轴向偏心孔 170〜油封201217667 VI. Description of the Invention: [Technical Field] The present invention relates to a drum brake mechanism, and more particularly to a drum brake mechanism that can effectively improve the braking effect of a brake. [Prior Art] Referring to FIG. 1A, FIG. 1B and FIG. 2, a conventional drum brake mechanism 1 mainly includes a fixed disk 10, a drum 20, a positioning pin 30, a cam 40, and a brake arm 50. A brake wire 60, a first brake shoe 71, a second brake shoe 72 and two tension springs 80. The drum 20 is sleeved in the fixed disk 10 in a rotating manner. Here, the drum 20 is a part of a wheel frame (not shown). The positioning pin 30 is attached to the fixed disk 10, and the positioning pin 30 is surrounded by the drum 20. As shown in Fig. 2, the cam 40 is sleeved in the fixed disk 10 in a rotating manner, and the cam 40 is also surrounded by the drum 20. The brake arm 50 is coupled to a cam 40 that can be used to drive the cam 40 to rotate. As shown in Figures 1A, 1B and 2, the brake wire 60 is coupled to the brake arm 50 which can be used to drive the brake arm 50 to rotate. The first brake shoe 71 and the second brake shoe 72 are disposed in the drum 20 in such a manner as to face each other. Here, the two ends of the first brake shoe 71 and the second brake shoe 72 are respectively abutted against the cam 40 and the positioning pin 30, and the first brake shoe 71 and the second brake shoe 72 are The friction drum 20 is detached in a detachable manner. 201217667 Two tension magazines 80 are connected between the first brake shoe 71 and the second brake shoe 72, which can maintain the two ends of the first brake shoe 71 and the second brake shoe 72 respectively. It abuts against the cam 40 and the positioning pin 30. When an operator wants to perform a braking operation on the drum 20 (or the wheel frame), the operator can pull the brake wire 60 by a brake operating device (not shown), thereby enabling the brake arm connected to the brake wire 60. 50 rotates an angle as shown in Figure 1B. At this time, the cam 40 connected to the brake arm 50 is also rotated by an angle so that the first brake shoe 71 and the second brake shoe φ shoe 72 are pivoted with the positioning pin 30 as a pivot point. Here, when the first brake shoe 71 and the second brake shoe 72 are distracted by the cam 40, the first brake shoe 71 will preferentially contact the drum 20 than the second brake shoe 72 due to structural constraints. . Since the cam 40 can only perform a rotational motion on the fixed disk 10 and cannot perform the displacement movement, the second brake shoe 72 cannot completely contact the drum 20, thus causing the second brake shoe 72 and the drum 20 to be in contact with each other. The friction area is insufficient, which in turn causes the brake function of the drum brake mechanism 1 to be poor. In view of the above, it is an object of the present invention to provide a drum brake mechanism that allows the first brake shoe and the second brake shoe to be subjected to equal braking force, thereby uniformizing wear and thereby enhancing The overall brake 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 fixed disk; a drum is sleeved in the fixed disk; a positioning pin is connected to the 201217667 [===:^? fixed disk; The sleeve is disposed on the bushing of the eccentric hole of the second wheel/set in the: partial:: and is abutted against the bushing and the cam:: sleeve 2: = drum: Γ the drum And a second brake shoe, which is provided with: and/or with respect to the first brake shoe, wherein t, the two ends of the fourth raised fourth shoe are respectively abutted to the wheel And the first pin' and the first brake shoe are slidably rubbed in a detachable manner. ',, the dry shoe is a drum brake mechanism according to the present invention, which further comprises at least one 1隹黄' is attached to the first brake shoe and the second brake shoe/in the present invention, the drum brake mechanism further includes a brake wire connected to the brake arm for driving the brake shoe The above-mentioned objects, features, and advantages of the present invention will become more apparent and obvious. The following detailed description of the preferred embodiments and the accompanying drawings [Embodiment] A preferred embodiment of the present invention will be described with reference to the drawings. Referring to Figures 3, 4 and 5, the drum brake mechanism 100 of the present embodiment may be suitable for a locomotive. And it mainly includes a fixed disc 110, a drum 120, a positioning pin 130, a bearing 14〇, a bushing 150, a cam 160, an oil seal 17〇, a brake arm 18〇, a brake wire 185, a first brake shoe 191, a second brake shoe 6 201217667 and two tension springs 195. The drum 120 is sleeved in the fixed disk 110. Here, the drum 120 is a wheel A part of the wheel frame (not shown). The positioning pin 130 is coupled to the fixed disk 110, and the positioning pin 130 is also surrounded by the drum 120. The bearing 140 is disposed in the fixed disk 110, and the bearing 140 is also The drum 120 is surrounded. As shown in Fig. 4, the bushing 150 is sleeved in the bearing 140, and φ and the bushing 15b has an axial eccentric hole 151. The cam 160 is sleeved on the shaft of the bushing 150. The oil seal 170 is disposed in the axial eccentric hole 151 of the bushing 150, and And the oil seal 170 is abutted between the bushing 150 and the cam 160. As shown in Figures 3, 4 and 5, the brake arm 180 is coupled to the cam 160, which can be used to drive the cam 160 to rotate. 185 is connected to the brake arm 180, which can be used to drive the brake arm 180 to rotate. • As shown in Fig. 3, the first brake shoe piece 191 and the second brake shoe piece 192 are disposed on the drum drum 120 in a manner opposite to each other. Here, the two ends of the first brake shoe 191 and the second brake shoe 192 are respectively abutted against the cam 160 and the positioning pin 130, and the first brake shoe 191 and the second brake shoe 192. The friction drum 120 is abuttable in a detachable manner. The two tension springs 195 are connected between the first brake shoe 191 and the second brake shoe 192, so that the two ends of the first brake shoe 191 and the two ends of the second brake shoe 192 are respectively abutted. When the cam 160 and the positioning pin 130 ° 201217667 field operator slave wheel drum 120 (or wheel wheel frame) brake operation, the operator can move 1 car (four) device (not (four)) to pull the brake wire 185 ' can make the connection The rotation angle of the arm (10) of the vehicle guide line 185 is as shown in Figs. 6A and 6B. At this time, the cam 160 connected to the brake arm 180 is also rotated by an angle. Here, it is worth noting that since the oil seal 170 is in contact with the bushing 15〇 and the cam 16〇, there is an impedance between the cam 160 and the bushing 15〇. On the other hand, since the bushing 150 is sleeved in the bearing 14A, the collar 15 can be freely rotated with respect to the fixed disk 11G. As described above, when the brake arm 18 〇 rotates the cam 160, the bush 15 〇 rotates in synchronization with the cam 16 ,, and the cam 16G disperses the first and second brake shoes 191 and the second brake shoe μ. Then, when the first brake shoe 91 is preferentially brought into contact with the drum drum 12, as shown in FIG. 6B, the cam 16〇 will continue to be driven by the brake arm 18〇. At this time, since the drum 120 (or the first brake shoe 191) exerts a (downward) reaction force on the cam 16 ,, the cam 16 〇 and the bush 15 开始 start to generate a relative rotational motion. More specifically, the set of 15 turns (counterclockwise) and the cam 16 套 sleeved in the axial eccentric hole 151 of the bushing 15G simultaneously produce (clockwise) rotation and (downward) displacement, (4) The second brake shoe piece 192 can be forced to make a firm contact with the drum drum 120, thereby increasing the area in which the second brake shoe piece 192 is in frictional contact with the drum drum 12G, as shown in Fig. 6c. As described above, in the operation of the drum brake mechanism disclosed in the embodiment, the 'first-turning shoe piece 191 and the second side-turning shoe piece 192 are subjected to equal braking force, thereby making the wear situation uniform. In turn, the overall brake effect can be improved. In addition, as shown in FIG. 6D, when the brake wire 185 is no longer pulling the 17201217667 arm 180, the two tension springs 195 will force the first brake shoe 191 and the second brake shoe 192 to separate from the drum 120. Release the brakes. At this point, the cam 160 and the bushing 150 again in a relative rotational motion and return to their original position, as shown in Figure 6A. Although the present invention has been disclosed in its preferred embodiments, it is not intended to limit the present invention, and it is possible to make some modifications and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims. 201217667 [Simple description of the drawing] A 1A figure shows a schematic plan view of a conventional drum type brake mechanism in a form of evil; the figure shows a schematic view of a conventional drum type brake mechanism in another type of operation; Figure 2 is a schematic cross-sectional view of the AA according to Figure 1A; = Figure shows a schematic plan view of the drum brake mechanism of the present invention; Figure 4 shows a schematic view of the BB according to Figure 3; Figure 5; Part of the mechanism of the mechanism, the drum type brake mechanism of the present invention is in the state of operation of the drum type brake mechanism in the state of operation (4) in the other state of operation, meaning: this: the drum type brake mechanism is - Kind of operation state (4) The drum car mechanism in the operation - the main component symbol description 1, 100 ~ drum brake mechanism 10, 〗 10 ~ fixed plate 2 () ' 120 ~ wheel drum, 130 ~ positioning 40,] 60~Cam 201217667 50, 180~ brake arm 60, 185~ brake wire 71, 191~ first brake shoe 72, 192~ second brake shoe 80, 195~ tension spring 140~ bearing 150~ lining 151~ axial eccentric hole 170 Seal