對于旋耕滅茬機(jī)械通用刀具轉(zhuǎn)子的研究

1、<p><b>　　畢業(yè)設(shè)計（論文）</b></p><p>　外文翻譯</p><p>　學(xué)生姓名陸金虎</p><p>　班 級11機(jī)設(shè)1 學(xué)號20110603122</p><p>　學(xué)院名稱機(jī)電工程學(xué)院</p><p>　專業(yè)名稱機(jī)械設(shè)計制造及其自動化（機(jī)械設(shè)計）<

2、;/p><p>　指導(dǎo)教師石榮玲</p><p>　　Study on universal blade rotor for rototilling</p><p>　　and stubble-breaking machine</p><p><b>　　Abstract</b></p><p>　　W

3、e have developed a dual-functional machine which can perform both rototilling and stubble-breaking operations. This machine is characterized by a universal rotor and blade mounting disc mechanism, thus the two operations

4、 are performed, respectively, by simple change of the blades. In this paper we present the analysis of the main parameters of the rototilling and stubble-breaking working parts and their effect on the operation quality o

5、n the basis of different agro-technical requirements. We al</p><p>　　the northeast of China and possesses several advantages compared with existing machines.</p><p>　　Keywords: Rototilling blade

6、; Stubble-breaking blade; Universal blade rotor; Multi-spiral arrangement; Rototilling and stubble-breaking machine</p><p>　　1. Introduction</p><p>　　Plowing with the traditional moldboard plows

7、 was used in the early years worldwide. However, this operation brought several problems that were gradually realized by farmers, agricultural engineers and researchers (Negi et al., 1981; Larney and Bullock, 1994; Olsen

8、 and Børresen, 1997; Lo´pez et al., 2000). These problems include severe wind and water erosion, increasingly worsening ecological environment, severe moisture loss in the soil and a significant decrease in so

9、il fertility. To overcome </p><p>　　The northeast of China, with average annual precipitation less than 450 mm in most years (Huang, 2000) and temperate climate, is a typical one crop per year dry farming ar

10、ea in the country. In this area the dry land accounts for 70% of the total farmland (Gao, 2000). Known as China’s “corn belt,” the principal agricultural crop is corn, and next to it are wheat, rice, soybean and others.

11、The ridge tillage system suitable to the dry and low temperature climate conditions has been developed during</p><p>　　Over the past 10 years, two tillage methods, stubble-breaking-shallow-rototilling (there

12、after referred to as stubble-breaking) and rototilling, have been widely adopted in the northeast of China. In ridge planting system, a stubble-breaking machine is used to break the stubbles of the crop left in the ridge

13、 and shallowly rototill the soil, playing a strip-ripping role. In the ridge planting system, typically for the corn field, is usually carried out in the autumn just after harvest. In the foll</p><p>　　The r

14、ototiller has long been developed and mature design methods exist (Hendrick and Gill, 1971a,b). In the literature, however, detailed studies on the stubble-breaking machine and on the dual-functional machine have been ra

15、rely reported. In this article we report our study and development of this dual-functional machine. In the following section we present the analyses of the kinematics of the working parts and the considerations in the de

16、sign of the rotor and blade mounting disc system. In Se</p><p>　　2. Kinematics analyses and determination of design parameters</p><p>　　The core working part of the rototilling and stubble-break

17、ing machine is the universal rototilling and stubble-breaking blade rotor. The blade parameter selection, the structure of the universal blade disc, blade arrangement and test methods are described as follows. </p>

18、<p>　　2.1. Blade motion parameters and the thickness of soil slice</p><p>　　The rototilling blades or stubble-breaking blades mounted on the blade disc complete the following compound motion: the circ

19、ular motion of the blade tip about the blade shaft, which is known as relative motion (its speed is the relative speed V0 (m/s) also known as the peripheral speed), the other is the convected motion in which the blade sh

20、aft (rotor) travels along with the machine (its speed is the convected speed Vm (m/s) or the travel speed of the machine). The parametric equations of their</p><p><b>　　(1)</b></p><p&g

21、t;　　where v is the angular speed of blade rotation (rad/s), R is turning radius of the blade tip. The absolute speed, V (m/s), which is a vector and is also called the cutting speed, can be written as</p><p>

22、;<b>　　(2)</b></p><p>　　The motion trajectory of the tip M of the rototilling blade (or the stubble-breaking blade) is a trochoid as shown in Fig. 1. Taking the center point, O, of the blade shaft

23、 as the origin of the coordinates, the positive direction of axis x is along the travel direction of the machine and the positive direction of y-axis is downward as shown in Fig. 1. Introducing time, t, the parametric eq

24、uation of the motion trajectory of point M (x, y) can be written as (Kanafojsk and Karwowski, 1976)</p><p><b>　　(3a)</b></p><p><b>　　(3b)</b></p><p>　　Elimin

25、ating time t from Eqs. (3a) and (3b), we can obtain the relationship between x and y at point M, </p><p>　　Fig.1. The trajectory of the blade tip. x: horizontal coordinate along machine travel direction; y:

26、vertical coordinate downward; R: radius of blade tip; : machine travel speed; v: rotary speed of blade tip; t: time; O: initial position of shaft where blade tip is horizontal; O0: position of shaft at time t; H: rotot

27、illing depth; : ground point where blade tip starts cutting soil; </p><p>　　M (x, y) point of blade tip at time t. seeing Fig. 1, as</p><p><b>　　(4)</b></p><p>　　By dif

28、ferential of Eqs. (3a) and (3b) we have the parametric equations of the speed components of the blade tip in x and y directions as</p><p><b>　　(5a)</b></p><p><b>　　(5b)</b&g

29、t;</p><p>　　Thus, the absolute value of the cutting speed V can be calculated by</p><p><b>　　(6)</b></p><p>　　Eq. (6) shows that V is a function of t and is influenced b

30、y the parameters ω, R and λ.</p><p>　　The thickness, S, of the soil slice is the displacement in the travel direction of two adjacent blades in the same tilling depth, which has a direct effect on the qualit

31、y of soil crushing and the smoothness of the furrow bottom. S is determined by the kinematical and structural parameters of the blade rotor (Li and Shouren, 1997). As shown in Fig. 2, S is the travel distance of the blad

32、e shaft during the period of when the blade disc rotates an angle of 2π/z, where z is the number of the blades</p><p><b>　　(7)</b></p><p>　　where n is rotation speed of the blade sh

33、aft (rotor) in unit of revolutions per minute (rpm). Eq. (7) shows that reduction of the thickness of soil slice can be realized by adjusting three parameters, by reducing the travel speed of the machine, by increasing t

34、he rotation speed of the blade shaft or by increasing the number of the blades, vice versa. As a quality index the smoothness of the furrow bottom can be represented by △h (see Fig. 2), that is the smaller the △h the smo

35、other the furrow bo</p><p>　　Fig.2. The thickness of soil slice S.</p><p>　　2.2. Structure of the universal blade disc</p><p>　　For a given travel speed of the machine, to meet diff

36、erent requirements of rototilling and stubble-breaking operations, the rotation speed of the blade shaft has to be changed (with a gear box) and the number of the blades should be adapted to the requirements of the opera

37、tions. The previous rototillers in the country use a blade holding mechanism which is easily blocked by mud or grass between the blade holders if the number of the blades (z > 2) increases, which affects the quality o

38、f operatio</p><p>　　As shown in Fig. 3, we determine the radius, r, of the blade disc first. As the maximum depth (about 16 cm) of the rototilling operation is larger than that (12–14 cm) of the stubble-brea

39、king operation, the radius of the blade disc should be selected to ensure that the blade disc does</p><p>　　not contact the soil when the machine conducts the rototilling operation in the maximum depth (Chin

40、ese Academy of Agricultural Mechanization Science, 1988), thus the following condition must be satisfied</p><p><b>　　(8)</b></p><p>　　where r is the radius of the blade disc, R the

41、turning radius of the blade tip and Hmax is the maximum tillage depth. Under the condition of Eq. (8), large value of r is desirable which allows reasonable arrangement of blade</p><p>　　mounting holes and m

42、akes it easy to change the blades. The commonly used turning radius R of the blade tip is 260 mm and maximum tillage depth 160 mm, thus the</p><p>　　maximum disc radius r given by Eq. (8) is 100 mm. In the d

43、esign r = 97 mm was chosen. In determination of the thickness of the blade disc both the strength and rigidity of the material during rototilling operation should be taken into consideration, from practical experience d

44、= 10 mm was chosen.</p><p>　　In the determination of the spacing F between two neighboring blade discs the agrotechnical requirements</p><p>　　of both rototilling and stubble-breaking operations

45、 have to be comprehensively taken into consideration. In order to meet the requirements of stubble-breaking, there should be such a relationship between the blade disc spacing F and the ridge spacing E given by</p>

46、<p><b>　　, or (9)</b></p><p>　　This ensures that the stubbles on every ridge can be fully broken by the blades. For the corn field in the northeast of China the common ridge spacing is 65

47、0 mm, then from Eq. (9) the blade disc spacing should be F = 130 mm. In this case, the centerline of the stubble-breaking area exactly aligns with the standard ridge spacing, and the machine can work normally within the

48、ridge spacing range of 600–700 mm.If F = 120 mm,it is suitable to the ridge spacing of 550–650 mm; if F = 140 mm, it is suit</p><p>　　In the rototilling operation, if there is no omission perpendicular to th

49、e working direction, then no strict restriction is applied to F. Therefore, in the determination of the disc spacing F the main consideration should be given to the requirements of the stubble-breaking operation. Fig. 4

50、sketchs the arrangement of the blade discs on the rotor.</p><p>　　The next step in the blade disc design is to determine the arrangement of mounting holes for both operations. The arrangement must ensure tha

51、t the blades are in their respective spiral arrangement and there is no interference</p><p>　　among the holes. First the arrangements of the holes for rototilling blades and for stubble-breaking blades are d

52、esigned separately; then a superimposing method is applied to examine if the spiral arrangement of the blades and the no-interference condition are satisfied. The optimized arrangement of the holes is gradually obtained

53、after several adjustments. Fig. 5a and b shows the arrangements of the mounting holes for the rototilling blades and for the stubble-breaking blades, respectively, an</p><p>　　According to the national stan

54、dards (National Standards of PR China, GB5668-85), the arrangement of rototilling blades on the discs should fulfil following conditions. (1) The blades of the right and left rotors are in multi-spiral arrangement and th

55、e spiral directions are symmetric to the centre line of the machine. The difference of phase angle at the initial positions between the right and left blade rotors is given by θ/2 = 180°/total lades on the right (or

56、 left) rotor. (2) The blades on the</p><p>　　rototilling blades, as shown in Fig. 6a, in which u/2 = 58. Under similar conditions and taking possible interference between rotortilling holes and the stubble-b

57、reaking holes into consideration, we obtained the arrangement of stubble-breaking blades, as shown in Fig. 6b. The rototilling and stubble-breaking machine with nine discs on each side, see Fig. 6, matches the Iron Cattl

58、e-804 tractor (58.8 kW). The design of the shape of rototilling blades follows the national standard (National Standa</p><p>　　standard to fit the universal disc. The blade is easily mounted on the disc wit

59、h two M12 bolts. The parameters of the rototilling blade are shown in Fig. 7a.</p><p>　　After several rounds of design and improvement, the parameters of the stubble-breaking blade were finally determined as

60、 shown in Fig. 7b.</p><p>　　The structural diagram of the rototilling and stubble-breaking machine is shown in Fig. 8. The machine is equipped with a speed change mechanism to adjust the rotation speed for t

61、he rototilling and stubble-breaking operations.</p><p>　　對于旋耕滅茬機(jī)械通用刀具轉(zhuǎn)子的研究</p><p><b>　　摘要</b></p><p>　　我們已經(jīng)開發(fā)出一種能夠同時執(zhí)行旋耕和滅茬的雙功能機(jī)。此機(jī)器的特征在于， 一個通用的轉(zhuǎn)子和刀片安裝盤機(jī)構(gòu)，由此可有兩個操作被執(zhí)行，這些

62、操作分別由刀片的簡單變化產(chǎn)生的。在本文中，我們在不同的農(nóng)業(yè)技術(shù)要求的基礎(chǔ)上對旋耕及滅茬工作零部件的主要參數(shù)和他們對操作質(zhì)量的影響進(jìn)行分析。我們還提出通用刀片的安裝系統(tǒng)的設(shè)計考慮因素，以確保兩個刀片可以無干擾地安裝在多螺旋裝置中?，F(xiàn)場試驗表明，與現(xiàn)有設(shè)備相??比，在中國的東北地區(qū)，這種雙功能機(jī)既滿足了農(nóng)業(yè)技術(shù)的要求且擁有幾大優(yōu)勢。</p><p>　　關(guān)鍵詞 旋耕刀片；滅茬刀具；通用刀片轉(zhuǎn)子；多螺旋排列；旋耕和滅茬

63、機(jī)1.簡介</p><p>　　早前世界范圍內(nèi)都是用傳統(tǒng)犁耕作土地的。然而，這種操作帶來了逐漸被農(nóng)民，農(nóng)業(yè)工程師和研究人員意識到了幾個問題（那迦等，1981；拉迪和布洛克，1994；奧爾森和布萊斯，1997；萊巴斯等，2000）。這些問題包括嚴(yán)重的風(fēng)蝕和水蝕，日益惡化的生態(tài)環(huán)境，土壤水分嚴(yán)重流失和土壤肥力下降顯著。為了克服這些問題，新的種植機(jī)，耕作和種植系統(tǒng)已經(jīng)發(fā)展了近一個世紀(jì)。自此對作物產(chǎn)量很多調(diào)查，土壤養(yǎng)分

64、和結(jié)構(gòu)，勞動力和燃料消耗比較不同的耕作和種植系統(tǒng)的影響已進(jìn)行了很多調(diào)查（維恩等，1990；艾格博格和萊利，1996；瑞吉等，1998；石道科等人，1999；陳等，2004）。</p><p>　　中國的東北地區(qū)，多數(shù)年份平均年降水量小于450毫米（黃，2000年）和溫帶氣候，在全國每年的旱作農(nóng)業(yè)區(qū)的一個典型的作物氣候帶。在這片區(qū)域內(nèi)旱地占總耕地的70％（高，2000年）。被稱為中國的“玉米帶”的主要農(nóng)作物是玉米，

65、而它旁邊的是小麥，水稻，大豆等。適合于干燥低溫氣候條件下的壟作系統(tǒng)在農(nóng)業(yè)實踐的悠久歷史被開發(fā)出來。在這個系統(tǒng)中，旱地作物如玉米和大豆要么種植在田埂要么或在之后形成的平地和田埂上。在作物生長過程中田埂保持不變。田埂的間距在60-70厘米的范圍內(nèi)，田埂的高度約為16厘米。平播系統(tǒng)適合于小麥，水稻和其他一些作物，在平播系統(tǒng)中作物種植在無起壟的平地。</p><p>　　在過去的10年中，兩耕作方法，滅茬和旋耕，已被廣泛

66、應(yīng)用在中國的東北地區(qū)。在壟作種植系統(tǒng)中，滅茬機(jī)是用來破碎留在田埂上的農(nóng)作物的根茬和淺耕土讓，起到了帶狀種植的作用。在壟作種植系統(tǒng)中，通常是在秋天剛剛收獲后才耕作玉米地。在下面的播種季節(jié)，明年春天，種子種在田埂上。在隨后的種植過程中，完整的田埂是通過培土形成。在平播種植系統(tǒng)，全幅旋耕（約12-16厘米）是有旋耕機(jī)操作完成的。例如在水田中，在春季首先進(jìn)行旋耕，其次是灌溉，平土，最后育苗移栽。這兩種耕作方式正逐步取代傳統(tǒng)的犁耕。最初是由兩個獨

67、立的機(jī)器執(zhí)行兩個耕作作業(yè)。近年來，在中國一些雙功能??機(jī)已經(jīng)發(fā)展到可以同時進(jìn)行滅茬和旋耕的工作了。目前這類機(jī)器有兩種類型，第一種機(jī)器裝有兩個轉(zhuǎn)子，一個用于安裝旋耕刀片和另一個用于滅茬刀片的安裝。對于每一個操作相應(yīng)的轉(zhuǎn)子安裝在機(jī)器上。在本機(jī)中的兩個轉(zhuǎn)子應(yīng)分別制造，然而這導(dǎo)致較高的制造成本，增加轉(zhuǎn)子的變化時間和勞動消耗。第二種機(jī)器的安裝旋耕刀片轉(zhuǎn)子和安裝滅茬刀片的轉(zhuǎn)子都安裝在同一臺機(jī)器上，并且對于一個動作時，其所需的功率被傳輸?shù)较鄳?yīng)的轉(zhuǎn)子。

68、這雙功能機(jī)是比以前的單功能機(jī)好，但是它也有一些缺點。第一個缺點是，由于</p><p>　　該旋耕機(jī)的開發(fā)和成熟的設(shè)計方法早就存在了（亨德里克和吉爾，1971a，b）。但在文獻(xiàn)中，對滅茬機(jī)器和雙功能機(jī)的詳細(xì)研究已鮮有報道。在這篇文章中，我們對這種雙功能機(jī)的研究和發(fā)展進(jìn)行了報道。在下面的部分中，我們對工作部件運動和轉(zhuǎn)子及刀片安裝盤系統(tǒng)的設(shè)計時所考慮的因素進(jìn)行了分析。在第3節(jié)我們提出了田間試驗結(jié)果與討論。結(jié)論總結(jié)在第

69、4節(jié)。</p><p>　　2.運動學(xué)分析和設(shè)計參數(shù)的確定</p><p>　　旋耕滅茬機(jī)的核心工作部分是旋耕及滅茬刀片工作時通用的轉(zhuǎn)子。刀片參數(shù)選擇，通用刀片安裝盤的結(jié)構(gòu)，刀片裝置和試驗方法描述如下。</p><p>　　2.1 刀片的運動參數(shù)和土壤切削的厚度</p><p>　　安裝在刀盤上的旋耕刀片或滅茬刀片可以完成以下的復(fù)合運動：刀片

70、軸上刀尖的圓周運動被稱為相對運動（其速度是相對速度（m/s）也被稱為圓周速度），另一種是牽連運動，其中，刀片軸（轉(zhuǎn)子）沿機(jī)器的行進(jìn)運動（其速度是牽連速度（米/秒），或者是機(jī)器的行進(jìn)速度）。他們的運動軌跡和運動速度的參數(shù)方程相同。相對速度與牽連速度的比例由（1）式給出</p><p><b>　?。?）</b></p><p>　　其中是刀片旋轉(zhuǎn)（弧度/秒）的角速度，R

71、是刀尖的圓角半徑。矢量絕對速度V（米/秒），也稱為切削速度，可以寫為（2）式</p><p><b>　　(2)</b></p><p>　　旋耕刀片（或滅茬刀片）的尖端M的運動軌跡是一擺線，如圖1所示。以刀片軸的中心點O作為坐標(biāo)原點的，軸線x的正方向是沿著機(jī)器的行進(jìn)方向和y軸的正方向是向下的，如圖1所示。引入時間t，點M（x，y）的運動軌跡的參數(shù)方程可以寫為（卡納負(fù)

72、基斯卡和卡若斯基，1976）</p><p><b>　　(3a)</b></p><p><b>　　(3b)</b></p><p>　　由式（3a）和（3b）消除時間t。我們可以得到在M點 x和y之間的關(guān)系。</p><p>　　圖1。刀尖的軌跡。 x：沿機(jī)器運行方向橫向坐標(biāo)；y：向

73、下垂直坐標(biāo)；R：刀尖圓角半徑；：機(jī)器行進(jìn)速度；：刀片尖端的旋轉(zhuǎn)速度；t：時間；O：軸的初始位置，刀尖是水平初始位置；：軸在t時刻的位置；H：旋耕深度；：刀尖開始切削土壤時地面上的點； 刀尖在時間t時刻的點M（x，y）。</p><p><b>　　由圖1可知</b></p><p><b>　　(4)</b></p>&l

74、t;p>　　由式（3a）和（3b）我們可得到刀尖x和y方向上的速度分量參數(shù)方程為</p><p><b>　　(5a)</b></p><p><b>　　(5b)</b></p><p>　　因此，在切削速度V的絕對值可通過（6）式計算</p><p><b>　　(6)</

75、b></p><p>　　式（6）顯示，V是關(guān)于時間t的函數(shù)，并且受參數(shù)ω，R和λ的影響。</p><p>　　土壤切削的厚度，S是在兩個相鄰的刀片以相同的耕作深度的行進(jìn)方向的位移，這對土壤粉碎的質(zhì)量和的光滑度有直接影響。 S由刀片轉(zhuǎn)子（李碩仁，1997年）的運動學(xué)和結(jié)構(gòu)參數(shù)來確定。如圖2所示，S是刀片軸在時間內(nèi)的行駛距離，是當(dāng)?shù)侗P旋轉(zhuǎn)2π/ z角度時的時刻，其中z是裝在同

76、一側(cè)的以等角度安裝在同一刀盤的刀片的數(shù)目。因此，對S簡單的描述后，S能寫為</p><p><b>　　(7)</b></p><p>　　其中n是在單位分鐘（rpm）內(nèi)刀片軸（轉(zhuǎn)子）的旋轉(zhuǎn)速度。式（7）顯示，可以通過調(diào)節(jié)三個參數(shù)、減少機(jī)器的行進(jìn)速度、增加刀片軸的轉(zhuǎn)速或通過增加刀片的數(shù)量減少土壤切削的厚度，反之亦然。作為品質(zhì)指標(biāo)的溝底部的平滑度可以通過△h（見圖2）來

77、表示，即越小的△h時溝底部越平滑。在這里，我們簡單地指出，增加R或減少S將導(dǎo)致△h減少。</p><p>　　圖2 土壤片的厚度S</p><p>　　2.2 萬能刀盤結(jié)構(gòu)</p><p>　　對于機(jī)器的給定行進(jìn)速度，以滿足旋耕滅茬的不同操作要求，必須改變刀片軸的旋轉(zhuǎn)速度（與齒輪箱）和刀片的數(shù)量應(yīng)根據(jù)要求的操作做出相應(yīng)的調(diào)節(jié)。在先前國內(nèi)使用的旋耕機(jī)是用一個刀片保持機(jī)

78、構(gòu)，這會使刀片夾持器之間容易被泥或草阻塞，如果刀片的數(shù)量（Z> 2）增加，操作的質(zhì)量將會收到影響，并且想要安裝滅茬刀片在上面幾乎是不可能的。因此，對于通用的轉(zhuǎn)子的發(fā)展的關(guān)鍵任務(wù)是刀盤（固定在轉(zhuǎn)子上）的設(shè)計，在不同的時間內(nèi)及針對不同的操作需求其上可以同時安裝旋耕刀片和滅茬刀片。</p><p>　　如圖3所示，我們首先需要確定刀盤的半徑r。由于旋耕操作的最大深度（大約16厘米）比滅茬操作（12-14厘米）的大

79、，應(yīng)選擇合適的刀盤半徑以確保當(dāng)機(jī)器旋耕作業(yè)達(dá)到最大深度時該刀片圓盤不與土壤接觸（中國農(nóng)業(yè)機(jī)械化科學(xué)，1988年），從而以下條件必須得到??滿足</p><p><b>　　(8)</b></p><p>　　其中，r是所述刀片圓盤的半徑，R是刀尖的圓角半徑和是最大耕作深度。在滿足式（8）的條件下，r應(yīng)適當(dāng)?shù)剡x取大值，這就可以它允許刀片安裝孔合理安排并可以很容易地轉(zhuǎn)換刀

80、片。刀尖圓角半徑R為260毫米，最大耕深為160毫米，因而可由公式（8）給出最大的刀盤半徑r為100毫米。在設(shè)計中r=97毫米。在判定刀盤厚度時應(yīng)同時考慮旋耕時材料的強(qiáng)度和剛性的厚度，由實際經(jīng)驗可知 =10毫米。</p><p>　　在判定兩個相鄰刀盤的間隔F時一應(yīng)全面考慮旋耕和滅茬操作的農(nóng)業(yè)技術(shù)要求。為了滿足滅茬的要求，刀盤間距F和田埂間距E應(yīng)該有這樣一種關(guān)系</p><p><b

81、>　　, or (9)</b></p><p>　　這確保了留在每個田埂上的根茬可以被刀片完全破碎。對于在中國的東北地區(qū)的玉米地中常見的田埂間距為650毫米，然后從公式（9）可知刀盤間距F = 130毫米。在這種情況下，滅茬區(qū)的中心線正好對準(zhǔn)標(biāo)準(zhǔn)壟間距，并且機(jī)器能夠在600-700 mm內(nèi)工作。如果 F =120毫米，合適的田埂間距為550-650毫米;當(dāng)F = 140毫米，合適的田埂間距為6

82、50-750毫米。</p><p>　　在旋耕操作中，如果在垂直于工作方向沒有遺漏，則對于F沒有嚴(yán)格的限制。因此，判定刀盤間距F時應(yīng)主要考慮滅茬操作的工作要求。圖4 簡述了轉(zhuǎn)子上的刀盤的位置安排。</p><p>　　刀盤設(shè)計的下一步驟是確定進(jìn)行兩個操作時安裝孔的排列。該裝置必須確保刀片在各自螺旋裝置中并且安裝孔之間相互沒有干擾。首先，對于旋耕刀片和滅茬刀片而言，安裝孔應(yīng)分別設(shè)計；然后可以

83、用疊加的方法檢查刀片的螺旋裝置是否合格及相互之間是否沒有干擾?？梢越?jīng)過多次調(diào)整逐步獲得孔的優(yōu)化布局。圖5a和b分別顯示了用于安裝旋耕刀片和滅茬刀片的安裝孔的布置，圖5c顯示出了同時安裝兩種類型刀具的孔的布置。這兩種類型的孔之間的相位角為 = 5°。目前對于孔的位置的設(shè)計的計算機(jī)軟件正在發(fā)展之中，當(dāng)輸入定量的充分條件和要求時，該計算機(jī)軟件將在幾秒內(nèi)秒自動獲得最優(yōu)化設(shè)計。</p><p>　　根據(jù)國家標(biāo)準(zhǔn)，

84、刀盤上旋耕刀具的安排應(yīng)符合以下條件。（1）轉(zhuǎn)子左右側(cè)多螺旋裝置刀片和螺旋方向關(guān)于機(jī)器的中心線是對稱的。左，右刀片轉(zhuǎn)子之間在初始位置的相位角之差為θ/ 2 = 180°/右（或左）轉(zhuǎn)子總安裝孔個數(shù)。 （2）對稱的刀盤及對稱的位置上的刀片依次穿透土壤，這樣會造成應(yīng)力均勻，減少沖擊和振動，軸向力平衡。（3）當(dāng)切削面積相同時，刀片的切削間距應(yīng)保證工作質(zhì)量和刀片均勻磨損。（4）同一刀盤的同一側(cè)的兩個相鄰刀片之間的角度應(yīng)大于24

85、°，以防止土壤和根茬堵塞刀片。在滿足這些條件的情況下，我們可以得到如圖6a所示的正確的旋耕刀片的布置，其中θ/ 2 = 58°。在類似條件下并考慮旋耕刀片安裝孔和滅茬刀片安裝孔之間可能產(chǎn)生的干擾，我們可得到滅茬刀片的布置，如圖6b所示。旋耕滅茬機(jī)械每邊有9個刀盤，如圖6所示，并由牛鐵-804拖拉機(jī)（58.8千瓦）驅(qū)動。</p><p>　　旋耕刀片的形狀的設(shè)計遵循國家標(biāo)準(zhǔn)（中國，GB5669-