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1、<p><b>  外文原文:</b></p><p>  The vertical Boom-type Roadheader design</p><p>  1 Introduction</p><p>  Mechanical design is in the process of product design and an i

2、mportant part of the main links, it is followed in programme design after the design work. The vertical Boom-type roadheader (the roadheader) to the overall design of the merits of complete machine play a decisive role,

3、and the decision of the assembly, the system, coordination between the various components of the unity and match, to obtain the high-end performance and overall better economic efficiency technology. Roadheader design,&l

4、t;/p><p>  2 the selected models and various components and structural type, drive, and the overall layout of the reasonable</p><p>  In determining the content, first task should be designed to me

5、et the contents, especially the users of the main demands of the investigation, the two sides exchanged views repeatedly, to satisfy both users (or superior) conditions, can better meet the product development of the ove

6、rall plan.</p><p>  2.1 the selected models</p><p>  According to roadheader use, for the coal mine tunnel boring or used for other sectors of the works, roadheader working conditions for cuttin

7、g coal roadway or semi-Coal Lane, the compressive strength of coal and rock one-way (or the value of platts coefficient f) and the rock abrasion factor. At the same time the control line should be superscript MT138 ~ 199

8、5 "cantilevered Roadheader types and parameters",</p><p>  according to cutting coal and rock the biggest one-way compressive strength, the type of selected models.</p><p>  2.2 the st

9、ructure of the various components, the way the driver identified</p><p>  Roadheader by cutting general agencies, shipping agencies, walking, hydraulic system, electronic control systems and auxiliary device

10、s (such as dust removal devices, security devices, remote monitoring devices) and other components. 1) Cutting agencies. Cutting the drive from AC motor-driven, in the transmission system located in the general profile c

11、oupling with no mechanical overload protection device, the two planets reducer driven spindle front of the cutting head. Some sections of the worki</p><p>  factor, loading good effect, the application is wi

12、despread. However, such institutions loading width restricted (because boring machine running track when agencies generally do not arouse). To expand the loading width, will shovel the entire harrow board, together with

13、the claw agencies in the level of swing, or design dual rake claws, to expand the scope of loading. Institutions than the rake-wheel-claw simple, high intensity, reliable, but with less bulk materials. Loading agency pro

14、gramme is </p><p>  and wear more serious. At present cross-section of the boring machine is usually used crawler-run institutions. Walking agencies tracked the general pattern, the two tracked separately by

15、 the respective power to drive, to achieve in situ. Caterpillar is the driving force of two motors and hydraulic motors, motor driver is generally set up a walking speed, hydraulic motor-driven large low-speed torque mot

16、or can be driven directly tracked sprocket, or used in the hydraulic motor speed Reducer led </p><p>  2.3 Layout</p><p>  General layout of the contents include the following: 1) Identify the c

17、omponents in complete machine said the location, shape and size of the request; 2) To identify the parts, components and the connections between complete machine; 3) estimates complete machine weight and the weight of al

18、l components requested; 4) layout of the manipulation of institutions, the driver's seat;</p><p>  5) examination of moving parts of the movement space, rule out the possibility of interference in the ca

19、mpaign.</p><p>  2.4 specific requirements</p><p>  Boring machine in the general layout, the need to pay attention to the following questions: 1) institutions into the reducer reducer, as far a

20、s possible to coax axis; 2) cantilever and spade-suited to the size of relations, not only conducive to loading, to avoid cutting the first shovel cutting board; 3) the level of cantilever and vertical position can swing

21、 the center coincidence, can not overlap. From the increased stability of the machine, these are highly swing should be reduced. In the ca</p><p>  2.5 types and power transmission components choice</p>

22、;<p>  transmission patterns and components should follow the principle of choice 1) the advanced nature of technology: machines to improve performance, increase productivity; 2) economic rationality: drive system

23、 as simple as possible, fewer components and easy processing, low price, easy maintenance, long life;</p><p>  3) reliability of the work: the transmission system reliability performance for the life of comp

24、onents, as well as component quality requirements; 4) adaptation: the drive system components should be adapted to load, working conditions and environmental conditions of the request. Agencies to the transmission system

25、 requirements and the choice of transmission patterns . Boring machine cutting, loading, transport, walking and other institutions generally are respectively transmission, all parts of</p><p>  3) walk the t

26、rack-driven approach and a motor-driven motor oil in two ways. Respectively, through mechanical devices or directly from the slowdown in motor oil led the initiative sprocket running track. Mechanical transmission of the

27、 walking track, with General Motors will be tracked in two reducer rear, the brake hydraulic braking by mechanical means way. This transmission mode drive high reliability and low prices of motor, easy maintenance, but n

28、ot speed, slow me larger, Lin Shui major roadwa</p><p>  3 determination complete machine main technology senate parameter</p><p>  Mechanical Roadheader complete machine main technical paramete

29、r including size senate parameter (length ×width ×highly); weight parameter, parameter of movement and dynamic parameter.</p><p>  3.1 size parameters</p><p>  Complete machine length,

30、 width of the size directly related to its turning radius, Recommended light-length ≤ 7.5 m, medium-length ≤ 8.5 m, heavy machine ≤ l0m, the corresponding width were ≤ 1.6 m, ≤ 2.5 m, ≤ 3 m. The complete machine relates

31、its tendency, the static stability highly directly, the adaptation scope and passes quality, therefore lower better. The current development trend of Chinese and foreign models is the dwarf models, medium and heavy-high

32、1.6 ~ 2 m, special light, light mach</p><p>  3.2 weight parameters</p><p>  The complete machine dead weight is the mechanical roadheader - an important parameter, the engine weight too is ligh

33、t, the work stability drops, when swinging cutting can occur fishtails the phenomenon, the cutting efficiency drops, truncation tooth rate of wear increase; Heavy-weight, poor mobility, flexibility to decline. The self-r

34、espect as it may be w = (t) estimates, in the N-type body for cutting power, kW; V for the cutting head on average cutting speed, m / s; can also be Roadheader wit</p><p>  ≤ 0.14 MPa; muddy for the water to

35、 soften the shale bottom, </p><p>  ≤ 0.05 MPa.</p><p>  3.3 movement parameters</p><p>  Cutting the movement parameters: cutting head of the average cutting speed V: on the one-wa

36、y coal and rock compressive strength of σ c ≤ 40 MPa, V = 3 ~ 3.5m / s;</p><p>  σ c ≤ 60MPa, V = 2 ~ 2.5m / s, σ c > 60MPa. V = l ~ 2m / s. But eventually cutting</p><p>  speed by cutting t

37、echnology to determine.</p><p>  3.4 dynamic parameters</p><p>  Roadheader-driven power sources are used Motors. Cutting power body size. In fact the general use of analogy, combined with roadh

38、eader some personality and</p><p>  experience factors to determine. Roadheader in the operating process, the vertical axis and the horizontal axis-of the need for adequate cutting edge and push forward swin

39、g (horizontal and vertical) force. According to Russia (the former Soviet Union) in the laboratory test results that the cutting of coal and rock platts hardness f = 4 ~ 6 (equivalent to 0 C = 40 ~ 60MPa), grinding coeff

40、icient F = 5 ~ 7mg/mm2. Cutting the shaking force (traction) Pv = (1 ~ 1.34) P, P = M / Rcp, in the P-cutting</p><p>  3.5 technical and economic indicators</p><p>  Q = (m3/min), in the sx-cutt

41、ing head for the verticalcross sectional area, m2: Vn for the cutting head of cutting swing speed, m / min. Roadheader designed life, in the international advanced products up to 3 to 5 years, during which the need of ma

42、jor repair or wells, the general domestic product for 1 to 2 years.</p><p>  4 in accordance with design requirements. Determine the parameters of the main components and their relationship between the conne

43、ctor</p><p>  4.1 cutting agencies and technical parameters of the established link between</p><p>  1) Cutting-agency technical parameters of cutting the head with the general pick for the doub

44、le-headed or three spiral layout. Cutting head speed n = 20 ~ 65r/min, a sharp pick cutting the average speed V = 1.5 ~ 2.5m / s, cutting swing speed Vn = 0.8 ~ l0m / s. Cut-off line from t = 20 ~ 50mm, (when cutting coa

45、l from the value of all-time for small value). Average single-pole/double-throw force should reach: f4 grade coal and rock F ≥ 2500 N, f6 grade coal and rock F ≥ 5000 N, f8 grade coal and</p><p>  slewing ri

46、ng size specifications. If the user does not require a cantilever stretching structure, is generally not recommended.</p><p>  4.2 shipping agencies determine the parameters</p><p>  1) Loading

47、mechanism Loading bodies and Middle conveyor used linkage or single-action mode, loading the bodies rake claws speed is generally 25 ~ 48 r / min. Star Ferry's speed can be slightly higher than some. Using direct-dri

48、ve hydraulic motors, the maximum output torque rated torque for calculating the value of 1.5 times. Shovel coal-general of the tilt angle to 21 ° ~ 25 °, it should be the width of track, spacious than the 0.6 ~

49、 1.2 m, declining position should not be less than the minimum </p><p>  4.3 running track and identify the technical parameters of connectivity between</p><p>  a)walking track drivers and tran

50、smission patterns have the following two ways, the overall design and layout determined at the time one of them. 1) Drive a motor-driven than reducer (i ≈ 250) → led initiative sprocket. Can only establish a walking spee

51、d of 5 ~ 7.5 m / min. 2) The speed of a hydraulic motor torque direct drive or take the initiative sprocket of a slowdown in high-speed motor driven me a sprocket can take the initiative to achieve rapid mobilization and

52、 the need to slow operations</p><p>  wear small chain of contacts. Heavy and severe roadheader recommend using this structure type. Track-installed at the bottom of the supporting wheels, each bearing capac

53、ity should be not less than 50 percent of weight, distance is generally tracked the plate pitch 1.5 times.</p><p>  4.4 the hydraulic system of technical parameters established</p><p>  Hydrauli

54、c system of technical parameters should be determined in the hydraulic design calculations. The pressure should not be rated higher than the 20 ~ 25 MPa. A hydraulic motor in the system should be set up power transmissio

55、n cooler, the system in the optional round series at the pump, rated pressure announced that the following 20 MPa. Selection of pumps and motors of the Anyu should be around 1.5. Each loop system in the pressure relief v

56、alve is set for the rated pressure of 1.8 to 2.2 tim</p><p>  4.5 electronic control system identified the main technical parameters</p><p>  Electronic control system of power supply voltage sh

57、ould be roadheader models to determine the size of pressure levels, special light, light machine should be elected 660 V, medium and heavy aircraft should be elected 660 V/1140V. Some momentum in the electrical circuit c

58、omponents, the power supply should meet the range of 70% to 115% of the requests.</p><p>  4.6 other supporting systems</p><p>  1) Spray system, cutting nozzles installed in the front organizat

59、ions cantilever pressure for 1.5 MPa. Spray nozzle within the system installed in cutting the first pick in the back seat of the spray system pressure of not less than 4 MPa. Cutting rock on the case should be to increas

60、e water pressure and water. 2) Inside and outside the water spray system shall not exceed the actual health roadheader capacity of 6 to 8 percent, or stagnant water in the face of slime.</p><p>  5 the overa

61、ll calculation of the necessary plans and systems</p><p>  Such as in roadheader design and overall layout is complete with two of the main components of each system and the main structure, the basic technic

62、al parameters have been determined, theComplete machine should carry out the necessary calculations and the overall system, and other plans. 1) Cutting agencies roadheader static and dynamic stability of the calculation.

63、 2) Transmission and hydraulic components of the electronic control system of power calculation.</p><p>  3) Hydraulic system heat balance calculations. 4) Drawing transmission, hydraulic, electronic control

64、 system plans. 5) Drawing cutting sections of roadway.</p><p>  6 Conclusion</p><p>  Roadheader design is roadheader design projects in the technical design of the components. It is the key to

65、the design of the overall performance parameters of reasonable choices, the assembly of each system and optimize the design standards, in particular, cutting the cutting technology is particularly important. Roadheader d

66、escribed in this paper, the overall design is still based on traditional design, dynamics, kinematics, the calculation of the force should be wider use of modern design met</p><p><b>  譯文:</b><

67、;/p><p>  懸臂縱軸式掘進(jìn)機(jī)的總體設(shè)計(jì)</p><p>  總體設(shè)計(jì)是機(jī)械產(chǎn)品設(shè)計(jì)過程中的重要內(nèi)容和主要環(huán)節(jié), 它是在方案設(shè)計(jì)之 后緊接著進(jìn)行的設(shè)計(jì)工作。 懸臂縱軸式掘進(jìn)機(jī)(以下簡(jiǎn)稱掘進(jìn)機(jī))的總體設(shè)計(jì)對(duì)整 機(jī)性能的優(yōu)劣起著決定性的作用, 并決定了各總成、 系統(tǒng)、 各部件之間的協(xié)調(diào)性, 統(tǒng)一性和匹配關(guān)系,從而獲得總體的高端 性能和較好的技術(shù)經(jīng)濟(jì)效益。 掘進(jìn)機(jī)的總體設(shè)計(jì),主要包括以下內(nèi)容:

68、 1)據(jù)設(shè)計(jì)任務(wù)書選擇機(jī)型及各部件結(jié)構(gòu)型式 2)定整機(jī)的主要技術(shù)性能參數(shù),包括尺寸參數(shù)、重量參數(shù)、運(yùn)動(dòng)參數(shù)和技 術(shù)經(jīng)濟(jì)指標(biāo) 3)按照總體設(shè)計(jì)的性能要求,確定整機(jī)系統(tǒng)的組成 及它們之間的匹配性以 及各個(gè)部件的主要技術(shù)參數(shù) 4)進(jìn)行必要的總體計(jì)算,并繪制傳動(dòng)、液壓、電控系統(tǒng)圖等。</p><p>  1.選定該機(jī)型和各個(gè)部件及其結(jié)構(gòu)型式、驅(qū)動(dòng)方式、并進(jìn)行總 體的合理布置</p><p>  該

69、項(xiàng)內(nèi)容在確定前,首先應(yīng)滿足設(shè)計(jì)任務(wù)書的內(nèi)容,特別是用戶提出的主要 要求經(jīng)過調(diào)研,雙方反復(fù)交換意見,達(dá)到既能滿足用戶(或上級(jí))條件,又能較好 的符合本企業(yè)產(chǎn)品發(fā)展的總體規(guī)劃。</p><p><b>  1)機(jī)型的選定</b></p><p>  根據(jù)掘進(jìn)機(jī)的用途, 是用于煤礦井下巷道的掘進(jìn)還是用于其他行業(yè)的工程作 業(yè),掘進(jìn)機(jī)的工作條件是用于截割煤巷還是半煤巖巷,煤巖的

70、單向抗壓強(qiáng)度(或 普氏系數(shù) f 值)及巖石的磨蝕系數(shù)。同時(shí)應(yīng)對(duì)照行標(biāo) MT138~1995《懸臂式掘進(jìn)機(jī) 的型式與參數(shù)》 ,按其截割煤巖的最大單向抗壓強(qiáng)度,選定機(jī)型的類別。</p><p>  2)各部件結(jié)構(gòu)型式、驅(qū)動(dòng)方式的確定</p><p>  掘進(jìn)機(jī)一般由截割機(jī)構(gòu)、裝運(yùn)機(jī)構(gòu)、行走機(jī)構(gòu)、液壓系統(tǒng)、電控系統(tǒng)及輔助 裝置(如除塵裝置、安全裝置、遙控 監(jiān)測(cè)裝置)等組成。 a.截割機(jī)構(gòu)。截割機(jī)

71、構(gòu)的驅(qū)動(dòng)方式由交流電動(dòng)機(jī)驅(qū)動(dòng),在傳動(dòng)系統(tǒng)中一般 設(shè)齒形聯(lián)軸節(jié),不設(shè)機(jī)械式過載保護(hù)裝置,經(jīng)兩級(jí)行星減速器帶動(dòng)主軸前端的截 割頭。 部分?jǐn)嗝婢蜻M(jìn)機(jī)的工作機(jī)構(gòu)有截鏈?zhǔn)?、圓盤銑削式和懸臂截割式等。因懸臂 截割式掘進(jìn)機(jī)機(jī)體靈活、體積較小,可截出各種形狀和斷面的巷道,并能實(shí)現(xiàn)選 擇性截割,而且截割效果好,掘進(jìn)速度較高;所以,現(xiàn)在主要采用懸臂截割式, 并已成為當(dāng)前掘進(jìn)機(jī)工作機(jī)構(gòu)的一種基本型式。</p><p>  按截割頭的布

72、置方式,分為縱軸和橫軸式兩種。 縱軸式截割頭的優(yōu)點(diǎn)是:傳動(dòng)方便、結(jié)構(gòu)緊湊,能截出任意形狀的斷面,易 于獲得較為平整的斷面,有利于采用內(nèi)伸縮懸臂,可挖柱窩或水溝。截割頭的形 狀有圓柱形、圓錐形和圓錐加圓柱形,由于后兩種截割頭利于鉆進(jìn),并使截割表 面較平整,故使用較多。這種工作機(jī)構(gòu)的缺點(diǎn)是:由于縱軸式截割頭在橫向擺動(dòng) 截割時(shí)的反作用力不通過機(jī)器中心,與懸臂形成的力矩使掘進(jìn)機(jī)產(chǎn)生較大的振 動(dòng), 故穩(wěn)定性較差。 因此, 在煤巷掘進(jìn)時(shí), 需加大機(jī)

73、身重量或裝設(shè)輔助支撐裝置。 目前,這種掘進(jìn)機(jī)在部分?jǐn)嗝婢蜻M(jìn)機(jī)中使用較多。 b.裝運(yùn)機(jī)構(gòu)。它一般由裝載機(jī)構(gòu)和中間輸送機(jī)組成。它們可采用分別驅(qū)動(dòng) 或集中聯(lián)動(dòng)方式,既可用交流電動(dòng)機(jī)驅(qū)動(dòng),也可用液壓馬達(dá)驅(qū)動(dòng)。 耙爪式是利用一對(duì)交替動(dòng)作的耙爪來不斷地耙取物料并裝入轉(zhuǎn)載運(yùn)輸機(jī)構(gòu)。 這種方式結(jié)構(gòu)簡(jiǎn)單、工作可靠、外形尺寸小、裝載效果好,目前應(yīng)用很普遍。但 這種裝載機(jī)構(gòu)寬度受限制(因?yàn)榫蜻M(jìn)機(jī)工作時(shí)履帶行走機(jī)構(gòu)一般不調(diào)動(dòng)) 。為擴(kuò) 大裝載寬度,可使鏟板連同

74、整個(gè)耙爪機(jī)構(gòu)一起水平擺動(dòng),或設(shè)計(jì)成雙耙爪機(jī)構(gòu), 以擴(kuò)大裝載范圍。 星輪式機(jī)構(gòu)比耙爪式簡(jiǎn)單、強(qiáng)度高、工作可靠,</p><p>  斷面掘進(jìn)機(jī)通常采用履帶式行走機(jī)構(gòu)。兩條履帶分別由各自的動(dòng)力來驅(qū)動(dòng),可實(shí) 現(xiàn)原地轉(zhuǎn)向。履帶的驅(qū)動(dòng)動(dòng)力有電動(dòng)機(jī)和液壓馬達(dá)兩種,電動(dòng)機(jī)驅(qū)動(dòng)一般只設(shè)置 一種行走速度,液壓馬達(dá)驅(qū)動(dòng)可采用低速大扭矩馬達(dá)直接帶動(dòng)履帶鏈輪,或采用 中速液壓馬達(dá)減速器帶動(dòng)履帶鏈輪的傳動(dòng)方式,它可實(shí)現(xiàn)無極調(diào)速。 履帶結(jié)構(gòu)

75、型式有滑動(dòng)和滾動(dòng)兩種,當(dāng)機(jī)器調(diào)動(dòng)速度≤10m/min 的中、輕型掘 進(jìn)機(jī),宜采用滑動(dòng)結(jié)構(gòu)型式;當(dāng)機(jī)器的調(diào)動(dòng)速度>10m/min 的重型、特重型掘進(jìn) 機(jī),應(yīng)采用滾動(dòng)結(jié)構(gòu)型式。 d.液壓系統(tǒng)。液壓系統(tǒng)多采用開式系統(tǒng)多路閥集中控制(直接操縱或遙控操 縱)方式。以往國(guó)內(nèi)外多采用齒輪泵,近年來掘進(jìn)機(jī)液壓系統(tǒng)采用柱塞泵有增多 的趨勢(shì)。 e.電控系統(tǒng)。電控系統(tǒng)包括動(dòng)力部分、控制部分和檢測(cè)部分。電控系統(tǒng)必 須按照煤礦井下防爆要求設(shè)計(jì)、制造、檢驗(yàn),

76、必須符合 GB3836-2000 標(biāo)準(zhǔn)中的 有關(guān)規(guī)定和要求。為了提高掘進(jìn)機(jī)在作業(yè)時(shí)的安全性,操作的靈活性 以及機(jī)械 傳動(dòng)部分的故障診斷及監(jiān)控功能,從實(shí)用角度考慮,裝設(shè)必要的離機(jī)遙控裝置、 測(cè)控壓力、溫度、液位及關(guān)鍵部位的故障診斷裝置。</p><p><b>  3)總體布置</b></p><p>  總體布置的內(nèi)容包括以下幾個(gè)方面: (1)確定各部件在整機(jī)說的位置

77、,并對(duì)外形尺寸提出要求; (2)確定各部件、部件與整機(jī)之間的連接方式; (3)估算整機(jī)重量,并對(duì)各部件的重量提出要求; (4)布置各操縱機(jī)構(gòu)、司機(jī)座位等; (5)審核個(gè)運(yùn)動(dòng)部件的運(yùn)動(dòng)空間,排除可能發(fā)生的運(yùn)動(dòng)干涉。</p><p><b>  4) 具體要求</b></p><p>  在掘進(jìn)機(jī)總體布置時(shí),需注意以下問題: (1)工作機(jī)構(gòu)減速器減速器的進(jìn)、出軸盡量同軸線

78、; (2)懸臂和鏟板的尺寸關(guān)系相適應(yīng),既有利于裝載,又要避免截割頭截割 鏟板; (3)懸臂的水平和垂直擺動(dòng)中心的位置可以重合,也可以不重合。從增加 機(jī)器的穩(wěn)定性看,擺動(dòng)這些都高度應(yīng)盡量降低。在保證懸臂不與其他機(jī)構(gòu)干涉的 條件下, 擺動(dòng)中心的位置應(yīng)盡量靠后, 但必須保證中心在機(jī)器的縱向?qū)ΨQ平面內(nèi); (4)當(dāng)各主要部件設(shè)計(jì)出來之后。應(yīng)進(jìn)行校核,不滿足需求時(shí)需僅需調(diào)整, 使重心位于履帶中心稍偏前且小于 L/6(L 為履帶接地長(zhǎng)度) 。此外,還

79、需求重心 位置在截割機(jī)構(gòu)回轉(zhuǎn)臺(tái)中心線之后,而且重心高度越低越好,以提高機(jī)器作業(yè)時(shí) 的穩(wěn)定性。</p><p> ?。?)總體布置應(yīng)考慮左右兩側(cè)重量對(duì)稱并照顧工作習(xí)慣及方便操作。司機(jī) 座一般設(shè)在機(jī)身左側(cè)、且位于機(jī)身后部,座椅高度應(yīng)保證司機(jī)的視線,使其哪個(gè) 很好地操縱機(jī)器,截割出規(guī)則的巷道; (6)操縱臺(tái)位置要適當(dāng),應(yīng)保證司機(jī)操縱方便、省力。儀表顯示裝置的位 置要便于司機(jī)觀察,又不分散司機(jī)正常操作的注意力。</

80、p><p>  5)傳動(dòng)型式及動(dòng)力元件的選擇</p><p>  a.傳動(dòng)型式及元件選擇應(yīng)遵循的原則 (1)技術(shù)先進(jìn)性:能夠改善機(jī)器性能,提高生產(chǎn)率; (2)經(jīng)濟(jì)合理性:傳動(dòng)系統(tǒng)盡量簡(jiǎn)單、元件少,易加工,價(jià)格低,維修容 易,使用壽命長(zhǎng); (3)工作可靠性:傳動(dòng)系統(tǒng)的可靠性表現(xiàn)為元件使用壽命,因此也是對(duì)元件 質(zhì)量的要求; (4)適應(yīng)性:元件應(yīng)適應(yīng)傳動(dòng)系統(tǒng)的載荷、工況及環(huán)境等條件的要求。 b.各機(jī)

81、構(gòu)對(duì)傳動(dòng)系統(tǒng)的要求及傳動(dòng)型式的選擇 掘進(jìn)機(jī)的截割、裝載、運(yùn)輸、行走等機(jī)構(gòu)一般均為分別傳動(dòng),各部件受力狀 態(tài)及工作條件不同,因而傳動(dòng)型式有不同的要求。 (1)工作機(jī)構(gòu)要求有較大的短時(shí)過載能力,而油馬達(dá)對(duì)沖擊負(fù)荷很敏感, 過載負(fù)荷能力低,影響截割頭正常連續(xù)運(yùn)轉(zhuǎn)。所以,掘進(jìn)機(jī)的工作機(jī)構(gòu)宜采用電 動(dòng)機(jī)為動(dòng)力的機(jī)械傳動(dòng)型式。應(yīng)利用體積小、功率大、過負(fù)荷能力強(qiáng)的專用電動(dòng) 機(jī),并配備可靠的電氣保護(hù)裝置。根據(jù)工作機(jī)構(gòu)結(jié)構(gòu)緊湊的特點(diǎn),通常工作機(jī)構(gòu) 的減速

82、器設(shè)在懸臂內(nèi),成為懸臂的組成部分。截割頭調(diào)速方式一般采用配換掛輪 的方法,變速機(jī)構(gòu)力求簡(jiǎn)單。 (2)耙裝機(jī)構(gòu)傳動(dòng)裝置的特點(diǎn)是:減速器需裝在尺寸有限的鏟板下部,因 而設(shè)計(jì)空間較小, 工作條件惡劣。 減速器經(jīng)常浸泡在煤巖泥水中, 卡料</p><p>  方式采用機(jī)械液壓制動(dòng)方式。這種傳動(dòng)方式傳動(dòng)可靠性高,電動(dòng)機(jī)價(jià)格低,維修 容易,但不能調(diào)速,減速箱體積較大,巷道淋水大時(shí),電動(dòng)機(jī)易受潮而燒毀。 履帶行走機(jī)構(gòu)采用液壓傳

83、動(dòng)型式,系統(tǒng)簡(jiǎn)單、性能較好、技術(shù)先進(jìn)。液壓傳 動(dòng)的行走機(jī)構(gòu)中,在液壓馬達(dá)型式選擇及調(diào)速方式設(shè)計(jì)方面,有不同的方案。 采用低速大扭矩馬達(dá)驅(qū)動(dòng),其特點(diǎn)是系統(tǒng)簡(jiǎn)單,尺寸小、重量輕,能夠?qū)崿F(xiàn) 無級(jí)調(diào)速及過載自動(dòng)保護(hù)。但液壓馬達(dá)傳動(dòng)復(fù)雜、制造費(fèi)用高,維護(hù)較難。 采用齒輪油馬達(dá),容積效率高,耐沖擊性能好,維修容易,造價(jià)較低,一臺(tái) 10KW 左右齒輪油馬達(dá)的價(jià)格只有同功率徑向柱塞馬達(dá)的 1/10;尺寸小、重量輕。 一臺(tái) 10KW 左右齒輪油馬達(dá)的重量

84、,僅為同功率低速大扭矩馬達(dá)的 1/18,為電動(dòng) 機(jī)重量的 1/13。采用齒輪油馬達(dá)后,減速器尺寸雖然較低速大扭矩馬達(dá)的大, 但較電動(dòng)式的?。∕RH-S50-13 型機(jī)的減速器傳動(dòng)比 i=328) 。因此可方便地將馬 達(dá)、減速器、液壓制動(dòng)閥、緊鏈裝置等安裝于履帶架中間。這種方式在技術(shù)性能 上優(yōu)于機(jī)械傳動(dòng), 在經(jīng)濟(jì)指標(biāo)上優(yōu)于低速大扭矩馬達(dá)傳動(dòng)。 因此具有獨(dú)特的優(yōu)點(diǎn)。 行走機(jī)構(gòu)的調(diào)速方式有兩種,一種</p><p> 

85、 2.確定整機(jī)主要技術(shù)參數(shù)</p><p>  掘進(jìn)機(jī)整機(jī)主要技術(shù)參數(shù)包括尺寸參數(shù) (長(zhǎng)×寬×高)、重量參數(shù)、運(yùn)動(dòng)參 數(shù)和動(dòng)力參數(shù)。</p><p><b>  1)尺寸參數(shù)</b></p><p>  整機(jī)長(zhǎng)度、寬度的大小直接與其轉(zhuǎn)彎半徑有關(guān),推薦輕型機(jī)長(zhǎng)度≤7.5m, 中型機(jī)長(zhǎng)度≤8.5m,重型機(jī)≤l0m,對(duì)應(yīng)的寬度分別

86、為≤1.6m,≤2.5m,≤3m。 整機(jī)的高度直接關(guān)系到它的動(dòng)、靜態(tài)穩(wěn)定性,適應(yīng)范圍和通過性的好壞,因 此越低越好。當(dāng)今中外機(jī)型發(fā)展趨勢(shì)是矮機(jī)型,中、重型機(jī)高度 1.6~2m,特輕 型、輕型機(jī)的高度 1.4~1.6m。掘進(jìn)機(jī)可掘巷道斷面的最大、最小高度和寬度應(yīng) 滿足設(shè)計(jì)任務(wù)書的要求。臥底深度 250~400mm,離地間隙 C=B/13+84(mm),B 為兩 履帶中心距)。中間輸送機(jī)龍門口過料高度最好為 400mm,履帶接地長(zhǎng)度 L 與

87、其 中心距 B 之比應(yīng)為 L/B≤1.6。</p><p><b>  2)重量參數(shù)</b></p><p>  整機(jī)自重是掘進(jìn)機(jī)的—個(gè)重要參數(shù),機(jī)重太輕,工作穩(wěn)定性下降,擺動(dòng)截割 時(shí)會(huì)發(fā)生擺尾現(xiàn)象、截割效率下降,截齒磨耗率增加;機(jī)重太重時(shí),機(jī)動(dòng)性差, 轉(zhuǎn)向靈活性下降?!闼淖灾乜砂?w=(t)估算,式中 N 為截割機(jī)構(gòu)功率,kW; V 為截割頭平均截割速度,m/s

88、;也可參照現(xiàn)有掘進(jìn)機(jī)用類比法來確定,機(jī)重(t) 與截割功率 (kW) 之比為 0. 25~0. 對(duì)于一般煤、 4。 巖底板, 許用值</p><p><b>  ≤0.14MPa;</b></p><p>  對(duì)于水軟化的泥質(zhì)頁巖底板,</p><p><b>  ≤0.05MPa。</b></p><

89、p><b>  3)運(yùn)動(dòng)參數(shù)</b></p><p>  截割機(jī)構(gòu)的運(yùn)動(dòng)參數(shù):截割頭的平均截割速度 V:對(duì)煤巖的單向抗壓強(qiáng)度 σ c ≤ 40MPa,V=3~3.5m/s; σ c ≤ 60MPa,V=2~2.5m/s, σ c >60MPa.V=l~2m/s。 但最終切割速度由切割技術(shù)來確定。</p><p><b>  4)動(dòng)力參數(shù)</

90、b></p><p>  掘進(jìn)機(jī)驅(qū)動(dòng)的動(dòng)力源都采用交流電動(dòng)機(jī)。截割機(jī)構(gòu)功率大小。實(shí)際上一般采 用類比法,再結(jié)合掘進(jìn)機(jī)一些個(gè)性因素及經(jīng)驗(yàn)來確定。 掘進(jìn)機(jī)在作業(yè)過程中,縱軸式和橫軸式部需要足夠的掏槽推進(jìn)力和擺動(dòng)(水 平方向和垂直方向)力。 根據(jù)俄羅斯(原蘇聯(lián))在實(shí)驗(yàn)室的試驗(yàn)結(jié)果得知,截割煤巖的普氏硬度 f=4~6(相當(dāng)于 0 C=40~60MPa),研磨系數(shù) F=5~7mg/mm2。截割時(shí)的擺動(dòng)力 (牽 引力)

91、Pv=(1~1.34)P,P=M/Rcp,式中 P 為截割頭上的平均截割力;Rcp 為截 割頭平均半徑; 為截割頭上的額定扭矩。 M 掏槽時(shí)的進(jìn)給力(軸向推力)R; (1.8~ 2.5)Pv,此力不得大于履帶對(duì)底板打滑時(shí)的極限牽引力。</p><p><b>  5)技術(shù)經(jīng)濟(jì)指標(biāo)</b></p><p>  Q=(m3/min),式中 sx 為截割頭的縱向橫截面積,m

92、2:Vn 為截割頭的截割擺 動(dòng)速度,m/min。 掘進(jìn)機(jī)的設(shè)計(jì)壽命,在國(guó)際上先進(jìn)的產(chǎn)品可達(dá) 3~5 年,在此期間它無需升 井大修,國(guó)內(nèi)產(chǎn)品一般為 1~2 年。</p><p>  3.按照總體設(shè)計(jì)的要求。 確定各主要部件參數(shù)及其相互之間的連 接關(guān)系</p><p>  1)截割機(jī)構(gòu)技術(shù)參數(shù)的確定及其連接關(guān)系</p><p>  (1)截割機(jī)構(gòu)技術(shù)參數(shù)的確定截割頭上的

93、截齒排列一般為雙頭或三頭螺旋 線布置方式。 截割頭轉(zhuǎn)速 n=20~65r/min, 截齒尖的平均截割速度 V=1. 5~2. 5m /s,截割擺動(dòng)速度 Vn=0.8~l0m/s。截線距離 t=20~50mm,(切煤時(shí)取大值, 切巖時(shí)取小值)。 平均單刀力應(yīng)達(dá)到: 級(jí)煤巖 F≥2500N, 級(jí)煤巖 F≥5000N, f4 f6 f8 級(jí)煤巖 F≥12000N,截齒安裝角最佳為 45°~48°。 (2)截割機(jī)構(gòu)的連接 截

94、割機(jī)構(gòu)懸臂安裝在叉形架前端,叉形架固定在回轉(zhuǎn)臺(tái)上,回轉(zhuǎn)臺(tái)固定在機(jī) 架上。根據(jù)截割機(jī)構(gòu)在作業(yè)過程中的作用力和力矩,應(yīng)用 MT475-1996《懸臂式 掘進(jìn)機(jī)回轉(zhuǎn)支承型式、基本參數(shù)和技術(shù)要求》選定回轉(zhuǎn)支承的結(jié)構(gòu)型式,通過計(jì) 算確定回轉(zhuǎn)支承規(guī)格尺寸。如用戶對(duì)懸臂不要求有伸縮結(jié)構(gòu),一般不推薦采用。</p><p>  2)裝運(yùn)機(jī)構(gòu)參數(shù)的確定</p><p>  (1)裝載機(jī)構(gòu) 裝載機(jī)構(gòu)與中間輸送機(jī)

95、采用聯(lián)動(dòng)方式或單動(dòng)方式, 裝載機(jī)構(gòu)耙爪的轉(zhuǎn)速一般 為 25~48r/min。星輪的轉(zhuǎn)速可略高一些。采用液壓馬達(dá)直接驅(qū)動(dòng)時(shí),最大輸出 扭矩應(yīng)為計(jì)算額定扭矩值的 1.5 倍。鏟煤板的傾斜角一般為 21°~25°,它 的寬度應(yīng)比履帶外寬大 0.6~1.2m,下降最低位置不應(yīng)小于臥底深度上升最大高 度應(yīng)達(dá)到 350~400mm。 (2)中間輸送機(jī) 中間輸送機(jī)的鏈條可采用單鏈或雙鏈結(jié)構(gòu)形式的圓環(huán)鏈,鏈速不應(yīng)超過 0.92m/s

96、,鏈條采用美國(guó)萬向套筒滾子鏈單鏈時(shí),鏈速不應(yīng)超過 2.5m/s,一般取 1.6~2m 為了滿足卸載高度的變化要求,機(jī)尾應(yīng)設(shè)多級(jí)升降液壓缸實(shí)現(xiàn)升降,升 起時(shí)的最小高度應(yīng)為受料斗高度加 300mm 左右。如機(jī)尾需要左右擺動(dòng)時(shí),必須采 用一條美國(guó)萬向套筒滾子鏈, 在轉(zhuǎn)向位置的一側(cè)設(shè)置單作用液壓缸實(shí)現(xiàn)機(jī)尾左右 擺動(dòng) 45°,以擴(kuò)大卸載的寬度。</p><p>  3)行走履帶技術(shù)參數(shù)的確定和連接關(guān)系</p

97、><p>  a.行走履帶的驅(qū)動(dòng)型式和傳動(dòng)方式有兩種, 總體設(shè)計(jì)和總體布置時(shí)確定其中 一種。 (1)電動(dòng)機(jī)驅(qū)動(dòng)一大傳動(dòng)比減速器(i≈250)→帶動(dòng)主動(dòng)鏈輪。 一般只能確定一種行走速度 5~7.5m/min。 (2)速大扭矩液壓馬達(dá)一直接驅(qū)動(dòng)主動(dòng)鏈輪或中高速馬達(dá)一減速箱一帶動(dòng)主 動(dòng)鏈輪能實(shí)現(xiàn)快速調(diào)動(dòng)和慢速作業(yè)的需要, 行走速度為 0~10m/min 的無級(jí)調(diào)速。 b.履帶傳動(dòng)的連接關(guān)系 結(jié)構(gòu)型式有滑動(dòng)和滾動(dòng)兩種 ,滑動(dòng)

98、式結(jié)構(gòu)簡(jiǎn)單,內(nèi)阻較大,對(duì)特輕型、輕 型、中型掘進(jìn)機(jī)推薦采用滑動(dòng)結(jié)構(gòu)式。滾動(dòng)式運(yùn)行阻力較小,履帶架底部與履帶 鏈相接觸磨損小。重型和特重型掘進(jìn)機(jī)推薦采用這種結(jié)構(gòu)型式。履帶架底部裝設(shè) 的支重輪,每個(gè)承載力應(yīng)不小于機(jī)重 50%,間距一般為履帶板節(jié)距的 1.5 倍。</p><p>  4) 液壓系統(tǒng)技術(shù)參數(shù)的確定</p><p>  液壓系統(tǒng)的技術(shù)參數(shù)的確定應(yīng)在液壓設(shè)計(jì)計(jì)算后定。 系統(tǒng)的額定工作

99、壓力不 宜高于 20~25MPa。在系統(tǒng)有液壓馬達(dá)傳動(dòng)動(dòng)力時(shí)應(yīng)設(shè)置冷卻器,系統(tǒng)中選用串 聯(lián)輪泵時(shí),額定壓力宣在 20MPa 以下。選用泵和馬達(dá)的安裕度應(yīng)為 1.5 左右。 系統(tǒng)中每個(gè)回路的溢流閥調(diào)定壓力為其額定壓力的 1.8~2.2 倍為宜。</p><p>  5)電控系統(tǒng)主要技術(shù)參數(shù)的確定</p><p>  電控系統(tǒng)的供電電壓應(yīng)按掘進(jìn)機(jī)機(jī)型大小來確定壓等級(jí),特輕型、輕型機(jī)應(yīng) 選 66

100、0V,中、重型機(jī) 型應(yīng)選 660V/1140V。動(dòng)力部分回路中的電器元件應(yīng)滿足供 電電的波動(dòng)范圍 70%~115%的要求。</p><p><b>  6)其他輔助系統(tǒng)</b></p><p>  1)外噴霧系統(tǒng),噴嘴設(shè)置在截割機(jī)構(gòu)懸臂的前端水壓為 1.5 MPa。 內(nèi)噴霧系統(tǒng)的噴嘴裝置設(shè)在截割頭截齒座的后面內(nèi)噴霧系統(tǒng)的壓力不低于 4MPa。對(duì)截割巖石的情況下應(yīng)適當(dāng)提

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