單級直齒圓柱減速器設(shè)計【F=1.25KN V=1.5ms D=250mm】
單級直齒圓柱減速器設(shè)計【F=1.25KN V=1.5ms D=250mm】,F=1.25KN V=1.5ms D=250mm,單級直齒圓柱減速器設(shè)計【F=1.25KN,V=1.5ms,D=250mm】,單級直齒,圓柱,減速器,設(shè)計,kn,ms,mm,妹妹
寧xx學院
《機械設(shè)計基礎(chǔ)》課程設(shè)計
單級直齒圓柱減速器
所在學院
專 業(yè)
班 級
姓 名
學 號
指導(dǎo)老師
年 月 日
29
機械設(shè)計課程設(shè)計計算說明書目錄
一、任務(wù)書 3
二、減速器的結(jié)構(gòu)形式 4
三、電動機選擇 4
四、傳動比分配 5
五、動力運動參數(shù)計算 6
六、V帶設(shè)計傳動零件的設(shè)計 7
七、齒輪的設(shè)計計算 10
八、軸的設(shè)計計算 15
九、軸承、鍵和聯(lián)軸器的選擇 19
十、箱體尺寸及附件的設(shè)計 25
總 結(jié) 28
參考文獻 29
致 謝 30
一、任務(wù)書
如下圖1-1,這是一個帶式運輸機傳動方案圖,
主要技術(shù)參數(shù):
1.原始數(shù)據(jù)
(1)運輸帶工作拉力:1.25KN=1250 F /N;
(2)運輸帶工作速度1.5v/(m.s-1) )
(3)卷筒直徑 250 D/mm.
2.工作條件
連續(xù)單向運轉(zhuǎn),載荷平穩(wěn),空載啟動,使用期限8年,小批量生產(chǎn),兩班制工作,運輸帶速度允許誤差±5%。
3.設(shè)計要求
采用一級圓柱直齒傳動
4.設(shè)計任務(wù)
編寫設(shè)計計算說明書1份(4000-6000字),繪制減速器裝配圖1張(A1圖紙),零件工作圖。
1-1
二、減速器的結(jié)構(gòu)形式
本減速器設(shè)計為水平剖分,封閉臥式結(jié)構(gòu)
三、電動機選擇
1、電動機類型的選擇: Y系列三相異步電動機
2、電動機功率選擇:
(1)傳動裝置的總功率:
從電動機到工作機的傳動總效率為:
其中、、、、分別為V帶傳動、齒輪傳動、滾動軸承、彈性套柱銷聯(lián)軸器和滾筒的效率,查取《機械基礎(chǔ)》P459的附錄3 選取=0.96 、=0.97(8級精度)、=0.99(球軸承)、=0.995、=0.96
故
(1)工作機的功率PW
(3)所需電動機功率Pd
又因為電動機的額定功率
查《機械基礎(chǔ)》P499的附錄50,選取電動機的額定功率大于為2.14kW,滿足電動機的額定功率 。
3、確定電動機轉(zhuǎn)速:
計算滾筒工作轉(zhuǎn)速:
按《機械設(shè)計課程設(shè)計手冊(第三版)》P5推薦的傳動比合理范圍,取圓柱齒輪傳動一級減速器傳動比范圍Ia=3~6。由相關(guān)手冊V帶傳動比I’1=2~4,則總傳動比理時范圍為Ia=6~24。故電動機轉(zhuǎn)速的可選范圍為n筒=(6~24)×119=714~2856r/min
符合這一范圍的同步轉(zhuǎn)速有750、1000、和1500r/min。
(4) 確定電動機的型號
選上述不同轉(zhuǎn)速的電動機進行比較,查《機械基礎(chǔ)》P499附錄50及相關(guān)資料得電動機數(shù)據(jù)和計算出總的傳動比,列于下表:
方案
電機型號
額定功率kW
電機轉(zhuǎn)速r/min
電機質(zhì)量kg
參考
價格(元)
總傳動比
同步
轉(zhuǎn)速
滿載轉(zhuǎn)速
1
Y100L1-4
2.2
1500
1440
38
760
12.57
2
Y112M -6
2.2
1000
960
63
1022
7.797
3
Y132S-8
2.2
750
720
79
800
6.083
表二
為降低電動機重量和價格,由表二選取同步轉(zhuǎn)速為1500r/min的Y系列電動機,型號為Y100L1-4。
查《機械基礎(chǔ)》P500附錄51,得到電動機的主要參數(shù)以及安裝的有關(guān)尺寸(mm),見以下兩表:
電動機的技術(shù)數(shù)據(jù)
電動機型號
額定功率
(kw)
同步轉(zhuǎn)速
(r/min)
滿載轉(zhuǎn)速
(r/min)
Y100L1-4
2.2
1500
1440
2.2
2.2
四、傳動比分配
工作機的轉(zhuǎn)速
取,則
五、動力運動參數(shù)計算
(1) 轉(zhuǎn)速n
(2)功率P
(3)轉(zhuǎn)矩T
把上述計算結(jié)果列于下表:
參數(shù)
軸名
輸入功率 (kW)
轉(zhuǎn)速(r/min)
輸入轉(zhuǎn)矩
(N.m)
傳動比
傳動效率
軸0(電動機軸)
2.14
1440
14.19
3
0.96
軸1(高速軸)
2.05
480
40.87
4.19
0.9603
軸2(低速軸)
1.99
114.56
156.3
1
0.9801
軸3(滾筒軸)
1.95
153.19
六、V帶設(shè)計傳動零件的設(shè)計
(1)計算設(shè)計功率Pd
表4 工作情況系數(shù)
工作機
原動機
ⅰ類
ⅱ類
一天工作時間/h
10~16
10~16
載荷
平穩(wěn)
液體攪拌機;離心式水泵;通風機和鼓風機();離心式壓縮機;輕型運輸機
1.0
1.1
1.2
1.1
1.2
1.3
載荷
變動小
帶式運輸機(運送砂石、谷物),通風機();發(fā)電機;旋轉(zhuǎn)式水泵;金屬切削機床;剪床;壓力機;印刷機;振動篩
1.1
1.2
1.3
1.2
1.3
1.4
載荷
變動較大
螺旋式運輸機;斗式上料機;往復(fù)式水泵和壓縮機;鍛錘;磨粉機;鋸木機和木工機械;紡織機械
1.2
1.3
1.4
1.4
1.5
1.6
載荷
變動很大
破碎機(旋轉(zhuǎn)式、顎式等);球磨機;棒磨機;起重機;挖掘機;橡膠輥壓機
1.3
1.4
1.5
1.5
1.6
1.8
根據(jù)V帶的載荷平穩(wěn),兩班工作制(16小時),查《機械基礎(chǔ)》P296表4,
取KA=1.1。即
(2)選擇帶型
普通V帶的帶型根據(jù)傳動的設(shè)計功率Pd和小帶輪的轉(zhuǎn)速n1按《機械基礎(chǔ)》P297圖13-11選取。
根據(jù)算出的Pd=2.42kW及小帶輪轉(zhuǎn)速n1=1440r/min ,查圖得:d d=112~140可知應(yīng)選取A型V帶。
(3)確定帶輪的基準直徑并驗證帶速
由《機械基礎(chǔ)》P298表13-7查得,小帶輪基準直徑為112~140mm
則取dd1= 112mm> ddmin.=75 mm(dd1根據(jù)P295表13-4查得)
表3. V帶帶輪最小基準直徑
槽型
Y
Z
A
B
C
D
E
20
50
75
125
200
355
500
由《機械基礎(chǔ)》P295表13-4查“V帶輪的基準直徑”,得=355mm
① 誤差驗算傳動比: (為彈性滑動率)
誤差 符合要求
② 帶速
滿足5m/s300mm,所以宜選用E型輪輻式帶輪。
總之,小帶輪選H型孔板式結(jié)構(gòu),大帶輪選擇E型輪輻式結(jié)構(gòu)。
(7)確定帶的張緊裝置
選用結(jié)構(gòu)簡單,調(diào)整方便的定期調(diào)整中心距的張緊裝置。
(8)計算壓軸力
由《機械基礎(chǔ)》P303表13-12查得,A型帶的初拉力F0=55N,上面已得到=161.74o,z=6,則
(9)帶輪的材料
選用灰鑄鐵,HT200。
本方案中帶輪為中小尺寸,選用腹板輪。
七、齒輪的設(shè)計計算
(1)選擇齒輪材料、熱處理方法及精度等級
① 齒輪材料、熱處理方法及齒面硬度
因為載荷中有輕微振動,傳動速度不高,傳動尺寸無特殊要求,屬于一般的齒輪傳動,故兩齒輪均可用軟齒面齒輪。查《機械基礎(chǔ)》P322表14-10,小齒輪選用45號鋼,調(diào)質(zhì)處理,硬度260HBS;大齒輪選用45號鋼,調(diào)質(zhì)處理,硬度為220HBS。
② 精度等級初選
減速器為一般齒輪傳動,圓周速度不會太大,根據(jù)《機械設(shè)計學基礎(chǔ)》P145表5-7,初選8級精度。
選小齒輪齒數(shù)Z1=20,則大齒輪齒數(shù)為Z2=i Z1,所以=4.1920=83.8
使兩齒輪的齒數(shù)互為質(zhì)數(shù),取值
(2)按齒面接觸疲勞強度設(shè)計齒輪
由于本設(shè)計中的減速器是軟齒面的閉式齒輪傳動,齒輪承載能力主要由齒輪接觸疲勞強度決定,其設(shè)計公式為:
② 確定載荷系數(shù)K
因為該齒輪傳動是軟齒面的齒輪,圓周速度也不大,精度也不高,而且齒輪相對軸承是對稱布置,根據(jù)電動機和載荷的性質(zhì)查《機械設(shè)計學基礎(chǔ)》P147表5-8,得K的范圍為1.4~1.6, 取K=1.5。
③ 小齒輪的轉(zhuǎn)矩
接觸疲勞許用應(yīng)力
?。┙佑|疲勞極限應(yīng)力
由《機械設(shè)計學基礎(chǔ)》P150圖5-30中的MQ取值線,根據(jù)兩齒輪的齒面硬度,查得45鋼的調(diào)質(zhì)處理后的極限應(yīng)力為
=600MPa , =560MPa
ⅱ)接觸疲勞壽命系數(shù)ZN
應(yīng)力循環(huán)次數(shù)公式為 N=60 n jth
工作壽命每年按300天,每天工作2×8小時,故
th=(300×10×2×8)=48000h
N1=60×466.798×1×48000=1.344×109
查《機械設(shè)計學基礎(chǔ)》P151圖5-31,且允許齒輪表面有一定的點蝕
ZN1=1.02 ZN2=1.15
ⅲ) 接觸疲勞強度的最小安全系數(shù)SHmin
查《機械設(shè)計學基礎(chǔ)》P151表5-10,得SHmin=1
ⅳ)計算接觸疲勞許用應(yīng)力。
將以上各數(shù)值代入許用接觸應(yīng)力計算公式得
ⅶ)齒寬系數(shù)
由于本設(shè)計的齒輪傳動中的齒輪為對稱布置,且為軟齒面?zhèn)鲃?,查《機械基礎(chǔ)》P326表14-12,得到齒寬系數(shù)的范圍為0.8~1.1。取。
ⅵ)計算小齒輪直徑d1
由于,故應(yīng)將代入齒面接觸疲勞設(shè)計公式,得
④ 圓周速度v
查《機械設(shè)計學基礎(chǔ)》P145表5-7,v1<2m/s,該齒輪傳動選用9級精度。
(1) 主要參數(shù)選擇和幾何尺寸計算
① 齒數(shù)
對于閉式軟齒面齒輪傳動,通常z1在20~40之間選取。為了使重合度較大,取z1=20,則z2=iz1=4.1920=83.8。使兩齒輪的齒數(shù)互為質(zhì)數(shù),最后確定z2=83。
② 模數(shù)m
標準模數(shù)應(yīng)大于或等于上式計算出的模數(shù),查《機械基礎(chǔ)》P311表14-1,選取標準模數(shù)m=3mm。
③ 分度圓直徑d
④ 中心距a
⑤ 齒輪寬度b
大齒輪寬度
小齒輪寬度
⑥ 其他幾何尺寸的計算(,)
齒頂高 由于正常齒輪,
所以
齒根高 由于正常齒
所以
全齒高
齒頂圓直徑
齒根圓直徑
名 稱
計 算 公 式
結(jié) 果 /mm
模數(shù)
m
3
壓力角
n
分度圓直徑
d1
60
d2
249
齒頂圓直徑`
齒根圓直徑
中心距
154.5
齒 寬
(2) 齒根校核
齒根彎曲疲勞強度的校核公式為
① 齒形系數(shù)YF
根據(jù)Z1、Z2,查《機械設(shè)計學基礎(chǔ)》P153表5-11,得YF1=2.81,YF2=2.24
② 彎曲疲勞許用應(yīng)力計算公式
ⅰ)彎曲疲勞極限應(yīng)力
根據(jù)大小齒輪的材料、熱處理方式和硬度,由《機械設(shè)計學基礎(chǔ)》P154圖5-33的MQ取值線查得
,
ⅱ)彎曲疲勞壽命系數(shù)YN
根據(jù)N1=6.722>和N2=>,查《機械設(shè)計學基礎(chǔ)》P156圖5-34得,
YN1=1 , YN2=1
ⅲ)彎曲疲勞強度的最小安全系數(shù)SFmin
本傳動要求一般的可靠性,查《機械設(shè)計學基礎(chǔ)》P151表5-10,取SFmin=1.2。
ⅳ)彎曲疲勞許用應(yīng)力
將以上各參數(shù)代入彎曲疲勞許用應(yīng)力公式得
ⅴ)齒根彎曲疲勞強度校核
因此,齒輪齒根的抗彎強度是安全的。
八、軸的設(shè)計計算
(1) 高速軸的設(shè)計
① 選擇軸的材料和熱處理
采用45鋼,并經(jīng)調(diào)質(zhì)處理,查《機械基礎(chǔ)》P369表16-1,得其許用彎曲應(yīng)力,。
② 初步計算軸的直徑
由前計算可知:P1=2.05KW,n1=480r/min
其中,A取112。
考慮到有一個鍵槽,將該軸徑加大5%,則
查《機械基礎(chǔ)》P458附錄1,取d=25mm
③ 軸的結(jié)構(gòu)設(shè)計
高速軸初步確定采用齒輪軸,即將齒輪與軸制為一體。根據(jù)軸上零件的安裝和固定要求,初步確定軸的結(jié)構(gòu)。設(shè)有7個軸段。
1段:該段是小齒輪的左軸端與帶輪連接,該軸段直徑為25mm,查《機械基礎(chǔ)》P475附錄23,取該軸伸L1=60mm。
2段: 參考《機械基礎(chǔ)》P373,取軸肩高度h為1.5mm,則d2=d1+2h=28mm。
此軸段一部分用于裝軸承蓋,一部分伸出箱體外。
3段:此段裝軸承,取軸肩高度h為1mm,則d3=d2+2h=30mm。
選用深溝球軸承。查《機械基礎(chǔ)》P476附錄24,此處選用的軸承代號為6306,其內(nèi)徑為30mm,寬度為19 mm。為了起固定作用,此段的寬度比軸承寬度小1~2mm。取此段長L3=17mm。
4段與6段:為了使齒輪與軸承不發(fā)生相互沖撞以及加工方便,齒輪與軸承之間要有一定距離,取軸肩高度為2mm,則d4=d6=d3+2h=33mm,長度取5mm,則L4= L6=5mm。
5段::此段為齒輪軸段。由小齒輪分度圓直徑d=60mm可知,d6=60mm。因為小齒輪的寬度為70mm,則L5=70mm。
7段:此段裝軸承,選用的軸承與右邊的軸承一致,即d7=30mm,L7=17mm。
由上可算出,兩軸承的跨度L=mm
④ 高速軸的軸段示意圖如下:
⑤ 按彎矩復(fù)合強度計算
A、圓周力:
B、徑向力:
ⅰ)繪制軸受力簡圖
ⅱ)繪制垂直面彎矩圖
軸承支反力:
由兩邊對稱,知截面C的彎矩也對稱。截面C在垂直面彎矩為
如圖
ⅲ)繪制水平面彎矩圖
ⅳ)繪制合彎矩圖
ⅴ)繪制扭轉(zhuǎn)圖
轉(zhuǎn)矩產(chǎn)生的扭剪力按脈動循環(huán)變化,取α=0.6,
ⅵ)繪制當量彎矩圖
截面C處的當量彎矩:
ⅶ)校核危險截面C的強度
軸上合成彎矩最大的截面在位于齒輪輪緣的C處,W=0.1d43
所以 軸強度足夠。
(2)低速軸的設(shè)計
① 選擇軸的材料和熱處理
采用45鋼,并經(jīng)調(diào)質(zhì)處理,查《機械基礎(chǔ)》P369表16-1,得其許用彎曲應(yīng)力,。
② 初步計算軸的直徑
由前計算可知:P2=1.99KW,n2=114.56r/min
計算軸徑公式:
即:
其中,A取106。
考慮到有一個鍵槽,將該軸徑加大5%,則
查《機械基礎(chǔ)》P458附錄1,取d=40mm
九、軸承、鍵和聯(lián)軸器的選擇
根據(jù)軸上零件得安裝和固定要求,并考慮配合高速軸的結(jié)構(gòu),初步確定低速軸的結(jié)構(gòu)。設(shè)有6個軸段。
1段: 此段裝聯(lián)軸器。裝聯(lián)軸器處選用最小直徑d1=40mm,根據(jù)《機械基礎(chǔ)》P482附錄40,選用彈性套柱銷聯(lián)軸器,其軸孔直徑為40mm,軸孔長度為60mm。根據(jù)聯(lián)軸器的軸孔長度,又由《機械基礎(chǔ)》P475附錄23,取軸伸段(即Ⅰ段)長度L1=58mm。
2段:查《機械基礎(chǔ)》P373,取軸肩高度h為1.5mm,則d2=d1+2h=mm
此軸段一部分長度用于裝軸承蓋,一部分伸出箱體外。
3段:取軸肩高度h為2.5mm,則d3=d2+2h=43+2mm。此段裝軸承與套筒。選用深溝球軸承。查機械基礎(chǔ)P476附錄24,此處選用的軸承代號為6209,其內(nèi)徑為50mm,寬度為18mm。為了起固定作用,此段的寬度比軸承寬度小1~2mm。取套筒長度為10mm,則此段長L3=(18-2)+10+2=28mm。
4段:此段裝齒輪,取軸肩高度h為2.5mm,則d4=d3+2h=mm。因為大齒輪的寬度為60mm,則L4=60-2=58mm
5段:取軸肩高度h為2.5mm,則d5=d4+2h=50mm,長度與右面的套筒相同,即L5=10mm。
6段:此段裝軸承,選用的軸承與右邊的軸承一致,即d6=40mm,L6=17mm。
由上可算出,兩軸承的跨度L=。
③ 低速軸的軸段示意圖如下:
④ 按彎矩復(fù)合強度計算
A、圓周力:
B、徑向力:
?。┣笾Х戳AX、FBY、FAZ、FBZ
ⅱ)由兩邊對稱,知截面C的彎矩也對稱。截面C在垂直面彎矩為
受力圖:
ⅲ)截面C在水平面上彎矩為:
ⅳ)合成彎矩為:
ⅴ)轉(zhuǎn)矩產(chǎn)生的扭剪力按脈動循環(huán)變化,取α=0.6,截面C處的當量彎矩:
ⅵ)校核危險截面C的強度
軸上合成彎矩最大的截面在位于齒輪輪緣的C處,W=0.1d43
所以軸強度足夠。
(3)確定滾動軸承的潤滑和密封
由于軸承周向速度為1m/s <2m/s,宜用軸承內(nèi)充填油脂來潤滑。滾動軸承外側(cè)的密封采用凸緣式軸承蓋和氈圈來密封。
(4)回油溝
由于軸承采用脂潤滑,因此在箱座凸緣的上表面開設(shè)回油溝,以提高箱體剖分面處的密封性能。
(5)確定滾動軸承在箱體座孔中的安裝位置
因為軸承采用脂潤滑,那么可取軸承內(nèi)側(cè)端面到箱體的距離為10mm,并設(shè)置封油盤,以免潤滑脂被齒輪嚙合時擠出的或飛濺出來的熱油沖刷而流失。
( 6 ) 確定軸承座孔的寬度L
,為箱座壁厚,,為箱座、箱蓋連接螺栓所需的扳手空間,查機械基礎(chǔ)表19-1得,?。?mm,C1=18mm,C2=16mm,L=8+18+16+8=50mm。
(7)確定軸伸出箱體外的位置
采用凸緣式軸承蓋,LH3型彈性柱銷聯(lián)軸器,高速軸軸承蓋所用螺栓采用規(guī)格為GB/T5782 M630,低速軸采用螺栓采用規(guī)格為GB/T5782 GB/T5782M835為了方便在不拆卸外接零件的情況下,能方便拆下軸承蓋,
查《機械基礎(chǔ)》附錄33,得出A、B的長度,則:
高速軸:L1>(A-B)=35-23=12mm;低速軸:L2>(A-B)=45-38=7mm
由前設(shè)定高速軸的L=60mm,低速軸的可知,滿足要求。
4、滾動軸承的選擇與校核計算
根據(jù)《機械基礎(chǔ)》P437推薦的軸承壽命最好與減速器壽命相同,取10年,一年按300天計算, T h=(300×10×2×8)=48000h
(1)高速軸承的校核
選用的軸承是6306深溝型球軸承。
軸承的當量動負荷為
由《機械基礎(chǔ)》P407表18-6查得,fd=1.2~1.8,取fd=1.2。
因為Fa1=0N,F(xiàn)r1= 518.8N,則
查《機械基礎(chǔ)》P407表18-5得,X= 1,Y= 0 。
查《機械基礎(chǔ)》p406表18-3得:ft=1 ,
查《機械基礎(chǔ)》p405得:深溝球軸承的壽命指數(shù)為=3 ,
Cr= 20.8KN;
則
所以預(yù)期壽命足夠,軸承符合要求。
(2)低速軸承的校核
選用6209型深溝型球軸承。
軸承的當量動負荷為
由《機械基礎(chǔ)》P407表18-6查得,fd=1.2~1.8,取fd=1.2。
因為Fa2=0N,F(xiàn)r2=492N,則
查《機械基礎(chǔ)》P407表18-5得,X=1 ,Y=0 。
查《機械基礎(chǔ)》p406表18-3得:ft=1 ,
查《機械基礎(chǔ)》p405得:深溝球軸承的壽命指數(shù)為=3 ,Cr=22.8KN;
則
所以預(yù)期壽命足夠,軸承符合要求。
5、鍵聯(lián)接的選擇及其校核計算
(1)選擇鍵的類型和規(guī)格
軸上零件的周向固定選用A形普通平鍵,聯(lián)軸器選用B形普通平鍵。
① 高速軸(參考《機械基礎(chǔ)》p471、附錄17,《袖珍機械設(shè)計師手冊》p835、表15-12a):根據(jù)帶輪與軸連接處的軸徑25mm,軸長為60mm,查得鍵的截面尺寸b=8mm ,h=7mm
根據(jù)輪轂寬取鍵長L=40mm
高速齒輪是與軸共同制造,屬于齒輪軸。
② 低速軸:
根據(jù)安裝齒輪處軸徑,查得鍵的截面尺寸,根據(jù)輪轂寬取鍵長。
根據(jù)安裝聯(lián)軸器處軸徑,查得鍵的截面尺寸,取鍵長L=50mm。
根據(jù)輪轂寬取鍵長L=72mm(長度比輪轂的長度小10mm)
(2)校核鍵的強度
① 高速軸軸端處的鍵的校核:
鍵上所受作用力:
?。╂I的剪切強度
鍵的剪切強度足夠。
ⅱ)鍵聯(lián)接的擠壓強度
<
鍵聯(lián)接的擠壓強度足夠。
② 低速軸兩鍵的校核
A、 低速軸裝齒輪軸段的鍵的校核:
鍵上所受作用力:
ⅰ)鍵的剪切強度
鍵的剪切強度足夠。
ⅱ)鍵聯(lián)接的擠壓強度
鍵聯(lián)接的擠壓強度足夠。
B、低速軸軸端處的鍵的校核:
鍵上所受作用力 :
?。╂I的剪切強度
鍵的剪切強度足夠。
ⅱ)鍵聯(lián)接的擠壓強度
鍵聯(lián)接的擠壓強度足夠。
(6)潤滑與密封
① 齒輪的潤滑
采用浸油潤滑,浸油深度為一個齒高,但不小于10mm。
② 滾動軸承的潤滑
由于軸承周向速度為1m/s <2m/s,所以選用軸承內(nèi)充填油脂來潤滑。
③ 潤滑油的選擇
齒輪選用普通工業(yè)齒輪潤滑油,軸承選用鈣基潤滑脂。
④ 密封方法的選取
箱內(nèi)密封采用擋油盤。箱外密封選用凸緣式軸承蓋,在非軸伸端采用悶蓋,在軸伸端采用透蓋,兩者均采用墊片加以密封;此外,對于透蓋還需要在軸伸處設(shè)置氈圈加以密封。
十、箱體尺寸及附件的設(shè)計
采用HT250鑄造而成,其主要結(jié)構(gòu)和尺寸如下:
中心距a=154.5mm,取整160mm
總長度L:
總寬度B:
總高度H:
箱座壁厚:,未滿足要求,直接取8 mm
箱蓋壁厚:,未滿足要求,直接取8mm
箱座凸緣厚度b: =1.5*8=12 mm
箱蓋凸緣厚度b1: =1.5*8=12mm
箱座底凸緣厚度b2:=2.5*8=20 mm
箱座肋厚m:=0.85*8=6.8 mm
箱蓋肋厚m1:=0.85*8=6.8mm
扳手空間: C1=18mm,C2=16mm
軸承座端面外徑D2:高速軸上的軸承:
低速軸上的軸承:
軸承旁螺栓間距s:高速軸上的軸承:
低速軸上的軸承:
軸承旁凸臺半徑R1:
箱體外壁至軸承座端面距離:
地腳螺釘直徑:
地腳螺釘數(shù)量n:因為a=160mm<250mm,所以n=4
軸承旁螺栓直徑:
凸緣聯(lián)接螺栓直徑: ,?。?0mm
凸緣聯(lián)接螺栓間距L:, 取L=100mm
軸承蓋螺釘直徑與數(shù)量n:高速軸上的軸承:d3=6, n=4
低速軸上的軸承: d3=8,n=4
檢查孔蓋螺釘直徑:,取d4=6mm
檢查孔蓋螺釘數(shù)量n:因為a=160mm<250mm,所以n=4
啟蓋螺釘直徑d5(數(shù)量):(2個)
定位銷直徑d6(數(shù)量): (2個)
齒輪圓至箱體內(nèi)壁距離: ,取 =10mm
小齒輪端面至箱體內(nèi)壁距離: ,取 =10mm
軸承端面至箱體內(nèi)壁距離:當軸承脂潤滑時,=10~15 ,取 =10
大齒輪齒頂圓至箱底內(nèi)壁距離:>30~50 ,取 =40mm
箱體內(nèi)壁至箱底距離: =20mm
減速器中心高H: ,取H=185mm。
箱蓋外壁圓弧直徑R:
箱體內(nèi)壁至軸承座孔外端面距離L1:
箱體內(nèi)壁軸向距離L2:
兩側(cè)軸承座孔外端面間距離L3:
2、附件的設(shè)計
(1)檢查孔和蓋板
查《機械基礎(chǔ)》P440表20-4,取檢查孔及其蓋板的尺寸為:
A=115,160,210,260,360,460,取A=115mm
A1=95mm,A2=75mm,B1=70mm,B=90mm
d4為M6,數(shù)目n=4
R=10
h=3
A
B
A1
B1
A2
B2
h
R
n
d
L
115
90
95
70
75
50
3
10
4
M6
15
(2)通氣器
選用結(jié)構(gòu)簡單的通氣螺塞,由《機械基礎(chǔ)》P441表20-5,取檢查孔及其蓋板的尺寸為(單位:mm):
d
D
D1
S
L
l
a
D1
M22 1.5
32
25.4
22
29
15
4
7
(3)油面指示器
由《機械基礎(chǔ)》P482附錄31,取油標的尺寸為:
視孔
A形密封圈規(guī)格
(4)放油螺塞
螺塞的材料使用Q235,用帶有細牙螺紋的螺塞擰緊,并在端面接觸處增設(shè)用耐油橡膠制成的油封圈來保持密封。由《機械基礎(chǔ)》P442表20-6,取放油螺塞的尺寸如下(單位:mm):
d
D0
L
l
a
D
S
d1
M24 2
34
31
16
4
25.4
22
26
(5)定位銷
定位銷直徑 ,兩個,分別裝在箱體的長對角線上。
=12+12=24,取L=25mm。
(6)起蓋螺釘
起蓋螺釘10mm,兩個,長度L>箱蓋凸緣厚度b1=12mm,取L=15mm ,端部制成小圓柱端,不帶螺紋,用35鋼制造,熱處理。
(7)起吊裝置
箱蓋上方安裝兩個吊環(huán)螺釘,查《機械基礎(chǔ)》P468附錄13,
取吊環(huán)螺釘尺寸如下(單位:mm):
d(D)
d1(max)
D1(公稱)
d2(max)
h1(max)
h
d4
M8
9.1
20
21.1
7
18
36
r1
r(min)
l(公稱)
a(max)
b(max)
D2(公稱min)
h2(公稱min)
4
1
16
2.5
10
13
2.5
箱座凸緣的下方鑄出吊鉤,查《機械基礎(chǔ)》P444表20-7得,
B=C1+C2=18+16=34mm
H=0.8B=34*0.8=27.2mm
h=0.5H=13.6mm
r2 =0.25B=6.8mm
b=2 =2*8=16mm
總 結(jié)
本次設(shè)計,使我進一步鞏固,加深和拓寬對機械原理,綜合運用液壓傳動,材料和其他專業(yè)課程知識的力學,分析和解決機械設(shè)計問題,知識。通過設(shè)計實踐,逐步樹立正確的設(shè)計思想,增強創(chuàng)新意識和競爭意識,熟悉機械設(shè)計的一般規(guī)律,分析問題和解決問題的能力。通過設(shè)計計算,圖紙和技術(shù)標準,應(yīng)用說明書,設(shè)計說明書和其他有關(guān)材料,機械設(shè)計的基本技能和綜合訓練。
因此,它在我們的四年大學生活中占有重要而又獨特的的地位。
參考文獻
[1]濮良貴,紀名剛,機械設(shè)計[M],高等教育出版社,2005
[2]孫桓,陳作模,機械原理[M],高等教育出版社,2005
[3]孫波,畢業(yè)設(shè)計寶典[M],西安電子科技大學出版社,2008
[4]. 楊黎明.機械零件設(shè)計手冊.北京:國防工業(yè)出版社,1996
[5]. 王昆等.機械設(shè)計(機械設(shè)計基礎(chǔ))課程設(shè)計.高等教育出版社,2006
[6]. 徐灝.機械設(shè)計手冊.北京:機械工業(yè)出版社,1995.12
[7]. 劉鴻文.材料力學Ι,第4版.北京:高等教育出版社,2006
[8]. 濮良貴等.機械設(shè)計,第八版.北京:高等教育出版社,2006。
[9]. 葉玉駒等.機械制圖手冊,第四版.北京:機械工業(yè)出版社,2008
致 謝
我要感謝我的指導(dǎo)教師XX老師。老師雖身負教學、科研重任,仍抽出時間,不時召集我和同門以督責課業(yè),從初稿到定稿,不厭其煩,一審再審,大到篇章布局的偏頗,小到語句格式的瑕疵,都一一予以指出。是他傳授給我方方面面的知識,拓寬了我的知識面,培養(yǎng)了我的功底,對論文的完成不無裨益。我還要感謝學院所有教過我的老師,是你們讓我成熟成長;感謝學院的各位工作人員,他細致的工作使我和同學們的學習和生活井然有序。
謹向我的父母和家人表示誠摯的謝意。他們是我生命中永遠的依靠和支持,他們無微不至的關(guān)懷,是我前進的動力;他們的殷殷希望,激發(fā)我不斷前行。沒有他們就沒有我,我的點滴成就都來自他們。
讓我依依不舍的還有各位學友、同門和室友。在我需要幫助的時候他們伸出溫暖的雙手,鼎立襄助。能和他們相遇、相交、相知是人生的一大幸事。
Introduction to the common speed reducer
Device overview:Reducer is the prime mover and work machine independent closed between the transmission device, used to reduce speed and increase torque, in order to meet the job needs, also used for growth in some occasions, known as the accelerator.
When choosing reducer should be according to the selection of working machine conditions, technical parameters, the performance of the engine, the factors such as economy, comparing the gabarite of different types and varieties of reducer, transmission efficiency and carrying capacity, quality, price, etc., choose the most suitable speed reducer.
Reducer is a relatively sophisticated machinery, the use of its purpose is to reduce rotation speed, increase torque.
Structural characteristics of
Reducer is mainly composed of transmission parts (gear or worm), shaft, bearing, box and its accessories. Its basic structure has three parts:
1.gear, shaft and bearing combination
Pinion and shaft made of an organic whole, gear shaft, this structure is used in the gear shaft and the diameter of the diameter of the weather related, if the diameter of the shaft is d, the gear tooth root circle diameter for df, when df - d 6 ~ 7 mn or less, this structure should be adopted. And when df - d > 6 ~ 7 mn, separated with gear and shaft for the two parts of the structure, such as low speed shaft and large gear. The gear and shaft circumferential fixed flat linkage, shaft parts shaft shoulder, shaft sleeve and bearing cover is used as the axial fixation. Two shaft adopts the deep groove ball bearings. This combination, the less used to bear radial load and axial load. When the axial load is larger, should adopt angular contact ball bearing, taper roller bearing and deep groove ball bearing and thrust bearing of composite structures. Bearing is the use of the gear rotates splashing through the thin oil, lubrication. Box medium oil pool of the lubricating oil, the rotation gear splash splash into the lid on the inner wall of the inner flow box side groove to points, through the oil flow into the bearing. Nu when oiled gear circumferential speed 2 m/s, or less grease lubricated bearings should be adopted, in order to avoid possible wash it splashing through the thin oil lubricating grease, the oil retaining ring can be used to separate it. To prevent loss of lubricating oil and dust into the trunk, between bearing end cover and outrigger shaft equipped with sealing element.
2. body
Enclosure is the important part in the reducer parts. It is the base of the transmission parts, should have sufficient strength and rigidity.
Cabinet is usually made of grey cast iron, for overloading or cast steel casing impact load reducer can also be used. Monomer production reducer, in order to simplify the process, to reduce the cost, can use steel plate welded box.
Gray cast iron has good casting and vibration reduction performance. To facilitate the shafting parts installation and disassembly, made along the axis line horizontal split-casing box body. On the box cover and the lower box body with a bolt connection into a whole. The connecting bolt of the bearing should be close to the bearing hole, and the bearing seat at the side of convex set, should have enough supporting material surface, in order to place the connecting bolt, and to ensure that the wrench to tighten bolts need to space. In order to ensure the body has enough stiffness, plus support rib near the bearing hole. In order to ensure the stability and reduce as much as possible on the basis of speed reducer in the mechanical processing of base plane of the area, the case base is generally not used the complete plane.
3. reducer fittings
In order to guarantee the normal work of the speed reducer, in addition to combination of gear, shaft, bearing and the structure design of box body is to give enough attention, also should be considered as reducer oil lubricating oil pool, oil discharge, check the oil level height, processing, maintenance when assembling and disassembling of the box cover and the box of accurate positioning, loading auxiliary parts and components, such as reasonable selection and design.
1) inspection to check the meshing condition of transmission parts, and to infuse lubricating oil contents, should be set in the appropriate location of the box body inspection hole. Inspection hole is located in the top lid can be observed directly on the gear mesh part. Normally, inspection hole of cover plate on the box cover with screws.
2) the ventilator speed reducer is working, the casing temperature, gas expansion pressure, to make overall thermal air free to discharge, to maintain pressure balance inside and outside, not make the lubricating oil or shaft extension along the points box surface seal leakage cracks and other, usually on the top of the box body installed ventilator.
3) bearing cover for the fixed shaft parts of axial position and carry axial load, the bearing hole on both ends with bearing cover closed. Bearing bore of flange type and embedded two kinds. Use hex bolt fixed on the box body, bearing cover is overhang shaft hole, which is equipped with sealing device. Flange type bearing cover has the advantage of tear open outfit, easy to adjust the bearing, but compared with the embedded bearing cover, the number of parts is bigger, the size is bigger, appearance is not smooth.
4) positioning pin every time in order to ensure the container cover, remained bearing hole processing accuracy, should be in before finishing the bearing hole, in the box cover and the box seats on the connecting flange of the locating pin. Placed vertically on both sides of the enclosure on the connecting flange, symmetrical body should be symmetrical arrangement, in order to avoid mistake.
5) oil level indicator to check the oil in the oil pool reducer hight, often maintain oil pool with just the right amount of oil, usually in the box body is convenient for observation, the oil level is relatively stable, installing the oil level indicator.
6) oil drain plug oil change, dirty oil and cleaner emissions, should be in the box seat, at the bottom of the oil pool of the lowest opening oil drain hole location, usually with a screw oil drain plug, oil drain plug and body joint face between gasket shall be leak proof.
7) seal screw for strengthening qi box, usually during assembly on housing subdivision surface coated with sodium silicate or sealant, when remove often due to the cementation close is difficult to open. So often the appropriate placement of the box cover connecting flange, work out ~ 2 screw holes, screwing in enlightening the box with a cylindrical side or flat side box screws. Gyration rev box screws can will cover on top. Small reducer also don't have rev. Cases of screw, when the lid with a screwdriver to pry out of the box cover, and the box can be the same as the size of the screw to the connecting bolt at the flange.
Main load
Machine with reducer connection work load condition is more complex, has much effect on the speed reducer, is one of the important factors, selection and calculation speed reducer the load state of the work machine (motivation) is the load condition, usually divided into three categories:
(1) - even load;
(2) - medium impact load;
(3) - strong impact load.
Design program
A, the original design information and data
1. the type of prime mover, specifications, speed, power (or torque), the startup characteristic, short-term overload capacity, the moment of inertia, etc.
2. the type of machine, specifications, use, speed, power (or torque). Working system: the constant load or changing load and variable load load diagram; Rev., braking and short-time overload torque, start frequency; Shock and vibration levels; Direction of rotation, etc.
3.the prime mover for machine and connection way of the reducer, shaft and if there is a radial force and axial force.
4.installation type (reducer and prime mover, the relative position of working machine, vertical and horizontal).
5.transmission ratio and its error is allowed.
6.the size and weight requirements.
7.to the degree of service life, safety and reliability requirements.
8.environmental temperature, dust concentration, air velocity and environmental conditions such as ph value; (if there is a circulating lubrication and cooling conditions, lubrication station) and the limitation on the vibration and noise.
9.to the requirements of operation and control.
10. the source of material, blank, standard parts and inventory.
11.factory manufacturing capabilities.
12.on volume, cost and price requirements.
13, the delivery date.
The article in the first four is a prerequisite, other aspects according to conventional design, such as the design life is generally! "Years. Used for important occasions, reliability should be higher.
Second, select the type of gear reducer and installation type
Three, set at the beginning of each process methods and parameters
Selected performance level, set at the beginning of the main parts of the gear and the material, heat treatment, finishing methods, lubrication, and lubrication oil.
Fourth, determine the transmission series
According to the total transmission ratio, to determine the transmission series and all levels of the transmission ratio.
Five, the initial geometry parameters
Early calculate gear transmission center distance (or pitch diameter), modulus and other geometric parameters.
Six, the overall design scheme
Determine the structure of the reducer, shaft size, span and the bearing model, etc.
Seven, check
Check the strength of the gear, shaft, key load, calculation of bearing life.
Eight, lubrication cooling calculation
To determine the speed reducer and accessory
Ten, gear carburized depth is determined
When necessary for tooth form and tooth to fix quantity calculation process data.
Eleven, drawing construction drawing
In the design should implement national and industry related standards.
Using the classification
1. reducer in use can be divided into two categories, general reducer and special reducer, design, manufacture and use of the two characteristics of each are not identical. 70-80 - s of the 20th century, reducer technology has made great development in the world, and closely integrated with the development of new technology revolution. The main types: gear reducer; Worm gear reducer; Gear - worm reducer; Planetary gear reducer.
2.general reducer has a helical gear reducer (including parallel shaft helical gear reducer, worm gear reducer, bevel gear reducer, etc.), planetary gear reducer, cycloid pin wheel reducer, the worm gear and worm reducer, planetary friction type mechanical stepless variable speed machine, and so on.
1) cylindrical gear reducer
Single stage level 2, level 2, level 2 above. Decorate a form: expansion, shunt type, coaxial type.
2) cone gear reducer
Used for the input shaft and output shaft position into the intersection.
3) worm gear reducer
Is mainly used for transmission ratio > 10 occasions, I drive more compact structure. Its defect is low efficiency. Wide application of Archimedes worm gear reducer.
4) gear - worm reducer
If gear drive level at high speed, the structure is compact;
If worm transmission at high speed, high efficiency.
5) planetary gear reducer
With a range of high transmission efficiency, transmission ratio, transmission power is 12 w ~ 50000 kw, small volume and weight
3.common types of reducer
1) the main characteristics of worm gear and worm reducer is a reverse self-locking function, can have a large reduction ratio, the input shaft and output shaft is not in the same axis, is not in the same plane. But generally larger, transmission efficiency is not high, the accuracy is not high.
2) harmonic reducer harmonic drive is to use the elastic deformation of flexible components controlled to transfer movement and power, small size, high precision, but the disadvantage is that soft wheel life is limited, don't impact resistance, rigidity compared with metal parts. Input speed cannot be too high.
3) planetary gear reducer, its advantage is more compact in structure, return clearance is small, high precision, long service life, rated output torque can do a lot of. But the price a little expensive. Reducer: in short, generally after the machine power in design and manufacture, the rated power will not change, at this time, the greater the speed, the smaller is the torque (or torque); Speed is smaller, the greater the torque.
The transmission ratio distribution principle
1. to make the bearing capacity of transmission at all levels are equal;
2. make all levels of transmission gear oil immersion depth is roughly similar in;
3.minimize the reducer for the shape of the size or weight, etc
Model selection
As far as possible choose close to ideal reduction ratio:
Reduction ratio = / servo motor speed reducer output shaft speed
Torque calculation:
For the life of the reducer, torque calculation is very important, and should pay attention to the maximum torque value of the acceleration (TP), which is super
Maximum load torque of reducer.
Apply power is usually the servo on market model for power, the applicability of the speed reducer is very high, can remain above 1.2 coefficient of work, but in use can also with their own needs to decide:
There are two main points:
A. choose servo motor output maximum diameter of axle diameter of axle is not greater than form.
B. If the computed torque, rotational speed can meet the normal operation, but in the net output servo have insufficient phenomenon, we can in the motor drive, do current limit control, or on the mechanical shaft torque protection, it is very necessary.
Installation method
The correct installation, use and maintenance of the reducer, it is an important link in ensure the normal operation of machinery and equipment. When you install reducer, therefore, please be sure to use related matters in strict accordance with the following installation, assembly and use seriously.
The first step is to install before confirm the motor and reducer are intact, and strict inspection of motor and reducer connected each part size matches, here is the positioning convex table of the machine, input shaft and gear reducer groove size and tolerance, etc.
The second step is to unscrew the gear reducer dustproof holes on flange lateral screw, adjust the clamping ring dustproof holes and side holes to make it align with each other, and insert the socket head screw. After taking the motor shaft key.
The third step is to connect the motor and the reducer nature. Connection must be to ensure the output gear reducer input shaft and motor shaft concentricity is consistent, and the outer flange is parallel. Such as concentricity is inconsistent, can lead to broken motor shaft or reducer gear wear and tear.
Check the maintenance
Different lubricant mixed ban each other. Oil level screw, oil drain plug and the location of the ventilator is determined by the installation position. Their relative position refer to the installation drawing to determine that speed reducer.
One, the oil level check
Cut off the power supply, prevent to get an electric shock! Waiting for reducer cooling!
Remove the oil level screw check filled with oil.
Install the oil level screw.
Second, the check of oil
Cut off the power supply, prevent to get an electric shock! Waiting for reducer cooling!
Open the oil plug, pick up sample.
Check the oil viscosity index
- if oil significantly turbidity, it is recommended that the replacement as soon as possible.
To bring oil level screw speed reducer
- check the oil level, whether qualified
- the installation of oil level screw
3.the oil replacement
After cooling oil viscosity increases with difficulty, reducer should be under the running temperature oil change.
Cut off the power supply, prevent to get an electric shock! Waiting for reducer cooled down no burning danger!
Note: when an oil change speed reducer should still keep warm.
Under the oil drain screw one by oil pan.
Open the oil level screw, ventilator and oil drain plug.
All the oil out.
Install drain plug.
Injection with brand new oil.
Oil shall conform to the installation location.
Check the oil level in the oil level screw.
Tighten the oil level screw and ventilator.
Failure to solve
Speed reducer leakage oil cause analysis and solution
Analysis of the causes
1.the pressure inside the tank
In closed reducer, each pair of gears meshing friction will emit heat, according to the Boyle trails by specific law, as the lengthen of running time, the deceleration box temperature gradually raised, and the reduction volume inside the case, so the pressure increase, in the case of lubricating oil splash, sprinkle on the inner wall of the deceleration box. Because the permeability of oil is strong, the overall pressure, which a seal is lax and the oil bleeding out from where.
2.the structure of the speed reducer design is not reasonable cause oil leakage
Such as design of reducer without ventilation hood, pressure reducer can not be achieved, in the pressure more and more high, oil leakage occurs.
3.a(chǎn)mount to much
Reducer in the process of operation, oil pool was badly agitation, lubricating oil splash around in the machine, if the amount is overmuch, make a lot of the place such as lubricating oil accumulation in the shaft seal, joint surface and lead to leakage.
4.improper maintenance technology
In equipment maintenance, due to the combined surface dirt removal is not complete, or sealant improper selection, seal, not timely replacement of seals, etc way can also cause oil leakage.
Treatment scheme
Governance using polymer composite materials to repair speed reducer leakage oil, polymer composite materials based on polymer, metal or ceramic powder, fiber and other materials for, under the action of curing agent, curing catalyst of composite materials. All kinds of material in performance from each other each other, to produce synergistic effect, the comprehensive performance is better than the original ingredients of composite materials. Have extremely strong sticky relay, mechanical properties, and chemical corrosion resistance and other performance, and therefore is widely used in metal equipment, mechanical wear, scratches, pits, cracks, leakage, repair such as casting sand holes, and chemistry of chemical storage tank, reaction tank, pipe anti-corrosion protection and restoration. For reducer static seal leakage point can use the ka wah polymer composite materials and technology field leakage of governance, without disassembly, polymer composite materials in the leakage of external governance, save time and effort, the effect is immediate, the product has excellent adhesion, oil resistance, and 350% of the tensile strength, overcome the impact of reducer vibration, well solved for many years for the enterprise is unable to solve the problem. If reducer running in static seal leak, the oil level of emergency repairing adhesive available surface engineering technologies NianDu, so as to achieve the aim of eliminate oil leakage.
Development trend
1.high level and high performance. Widely used cylindrical gear carburizing and quenching, grinding, carrying capacity increased by more than 4 times, small volume, light weight, low noise, high efficiency and high reliability.
2.modular combination design. Basic parameters using priority number, size, parts versatility and interchangeability, series of easy to expand and newer, conducive to tissue mass production and reduce cost.
3.style diversification, variant design. To get rid of the traditional single base installation, added a hollow shaft mounted, floating bearing base, motor and reducer one-piece, different types, such as multiple mounting surface for expanding the
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