手提式挖坑機(jī)開合螺母式自動(dòng)進(jìn)給機(jī)構(gòu)的設(shè)計(jì)與試驗(yàn)

馬麗娜，王警梁，宗望遠(yuǎn)，黃小毛，馮 軍

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手提式挖坑機(jī)開合螺母式自動(dòng)進(jìn)給機(jī)構(gòu)的設(shè)計(jì)與試驗(yàn)

馬麗娜，王警梁，宗望遠(yuǎn)※，黃小毛，馮 軍

（華中農(nóng)業(yè)大學(xué)工學(xué)院，武漢 430070）

挖坑機(jī)鉆頭進(jìn)給量是影響其扭矩和工作效率的重要因素，研究挖坑機(jī)進(jìn)給量與其動(dòng)態(tài)力學(xué)參數(shù)之間的變化規(guī)律對(duì)開發(fā)挖坑機(jī)具有重要意義。該文首先根據(jù)開合螺母的工作原理，利用解析法分析了開合螺母機(jī)構(gòu)的運(yùn)動(dòng)特性，確定出了其動(dòng)銷軌道角為105°，進(jìn)而設(shè)計(jì)出了一種開合螺母式自動(dòng)進(jìn)給機(jī)構(gòu)的手提式挖坑機(jī)，不僅實(shí)現(xiàn)了挖坑作業(yè)的自動(dòng)化，又能迅速完成回程運(yùn)動(dòng)。然后基于挖坑機(jī)升土理論，分析了挖坑機(jī)鉆頭進(jìn)給量與其升土效果之間的影響關(guān)系，并通過試驗(yàn)進(jìn)行了驗(yàn)證，從而為挖坑機(jī)進(jìn)給量的設(shè)計(jì)提供了參考。研究表明，開合螺母螺距為5 mm時(shí)，挖坑機(jī)扭矩及其波動(dòng)幅度均較小、工作效率最高。

機(jī)械化；設(shè)計(jì)；土壤；挖坑機(jī)；開合螺母；自動(dòng)進(jìn)給；鉆頭進(jìn)給量；扭矩

0 引 言

挖坑機(jī)是一種用途廣泛、結(jié)構(gòu)簡單、操作方便的挖坑整地機(jī)械，主要有懸掛式、手提式、牽引式和自走式四類。而在山地、丘陵、溝壑等復(fù)雜地形工況下普遍采用手提式挖坑機(jī)進(jìn)行果樹栽植、橡膠定植、小樹移植和挖追肥穴等的作業(yè)[1]。

目前，國內(nèi)外學(xué)者普遍采用試驗(yàn)研究了挖坑機(jī)動(dòng)態(tài)力學(xué)參數(shù)對(duì)其扭矩、功率和工作效率的影響規(guī)律[2-6]，分析了挖坑機(jī)鉆頭、支撐機(jī)構(gòu)、主軸等結(jié)構(gòu)的動(dòng)力學(xué)特性和振動(dòng)特性[7-14]，對(duì)其結(jié)構(gòu)進(jìn)行了優(yōu)化。為適應(yīng)特殊環(huán)境作業(yè)工況的要求，并達(dá)到提高工作效率和降低勞動(dòng)強(qiáng)度[15-16]的目的，設(shè)計(jì)了以液壓為動(dòng)力[17-18]或具備新型進(jìn)給機(jī)構(gòu)[19-24]以及仿生鉆頭[25]等結(jié)構(gòu)的自動(dòng)化及智能化的新型挖坑機(jī)，甚至設(shè)計(jì)出了挖坑機(jī)器人[26]，但其普遍造價(jià)高、使用周期短，而且受到工作條件限制[27]。對(duì)于挖坑機(jī)鉆頭進(jìn)給量的控制，多采用液壓或手動(dòng)等方式實(shí)現(xiàn)[28-30]，尚未明確機(jī)械式挖坑機(jī)進(jìn)給量的設(shè)計(jì)方法。此外，現(xiàn)有手提式挖坑機(jī)多無支架，不僅坑穴的垂直度得不到保障，大大增加了挖坑機(jī)鉆頭扭矩，嚴(yán)重制約著結(jié)構(gòu)的可靠性和穩(wěn)定性，而且增大了挖坑作業(yè)過程中的不安全因素。

因此，本文基于挖坑升土理論，確定了挖坑機(jī)的進(jìn)給量，并結(jié)合開合螺母機(jī)構(gòu)的工作原理，設(shè)計(jì)出了一種開合螺母式自動(dòng)進(jìn)給機(jī)構(gòu)的手提式挖坑機(jī)。

1 手提式挖坑機(jī)開合螺母式自動(dòng)進(jìn)給機(jī)構(gòu)的設(shè)計(jì)

1.1 開合螺母式自動(dòng)進(jìn)給機(jī)構(gòu)螺距的設(shè)計(jì)

根據(jù)挖坑機(jī)升土理論[31]可知，影響鉆頭順利升土的主要因素有2個(gè)，即鉆頭轉(zhuǎn)速和鉆頭進(jìn)給量。鉆頭進(jìn)給量一定時(shí)，鉆頭實(shí)際轉(zhuǎn)速超過臨界轉(zhuǎn)速時(shí)土壤向上流動(dòng)，挖坑機(jī)順利升土。鉆頭轉(zhuǎn)速一定時(shí)，鉆頭進(jìn)給量則是影響鉆頭升土效果和挖坑效率的關(guān)鍵因素。手提式挖坑機(jī)自動(dòng)進(jìn)給機(jī)構(gòu)采用絲杠螺母?jìng)鲃?dòng)的進(jìn)給方式，該自動(dòng)進(jìn)給機(jī)構(gòu)的螺距即決定了挖坑機(jī)的進(jìn)給量。

挖坑機(jī)鉆頭工作時(shí)，當(dāng)土壤垂直運(yùn)動(dòng)速度大于土壤堵塞臨界速度時(shí)鉆頭能夠正常工作，而不發(fā)生堵塞現(xiàn)象。

土壤垂直運(yùn)動(dòng)速度[1]為

式中v為土壤垂直運(yùn)動(dòng)速度，m/s；0為鉆頭半徑，m；為鉆頭轉(zhuǎn)速，rad/s；為土壤速度損失系數(shù)；為鉆頭升角，(°)；2為土壤之間摩擦系數(shù)；為鉆頭半徑處的質(zhì)點(diǎn)速度與水平面的夾角，(°)；與為系數(shù)；1為土鋼摩擦角，一般取20°；為重力加速度，9.8 m/s2。

鉆頭進(jìn)給速度[31]v為

避免鉆頭堵塞臨界條件為

式中為鉆頭進(jìn)給量，mm/r；為土壤彭松系數(shù)，取1.6。

本文中選用的鉆頭半徑為0.15 m，鉆頭升角為20°。根據(jù)文獻(xiàn)[1]，土鋼摩擦角和土壤內(nèi)摩擦角分別取20°和44°。由式（1）～式（3），可得出土壤垂直速度和堵塞臨界速度分別隨鉆頭進(jìn)給量變化曲線，如圖1所示。

由圖1可知，土壤垂直速度和堵塞臨界速度隨進(jìn)給量變化曲線相交于點(diǎn)（5.3，0.048）。當(dāng)進(jìn)給量小于5.3 mm/r時(shí)，土壤垂直運(yùn)動(dòng)速度大于鉆頭堵塞臨界速度，挖坑機(jī)能夠正常升運(yùn)土壤。當(dāng)進(jìn)給量大于5.3 mm/r時(shí)，土壤垂直速度小于鉆頭堵塞臨界速度，挖坑機(jī)鉆頭發(fā)生堵塞。當(dāng)鉆頭進(jìn)給量滿足順利升土條件時(shí)，進(jìn)給量越大，挖坑效率越高。結(jié)合螺母絲杠螺距在國標(biāo)中的規(guī)定，開合螺母螺紋規(guī)格選為Tr24×5，即直徑為24 mm，螺距為5 mm的梯形螺紋。為匹配挖坑機(jī)鉆頭旋向和動(dòng)力輸出軸的轉(zhuǎn)向，自動(dòng)進(jìn)給機(jī)構(gòu)螺紋旋向設(shè)計(jì)為右旋。

1.2 開合螺母結(jié)構(gòu)設(shè)計(jì)

采用螺紋傳動(dòng)能夠?qū)崿F(xiàn)挖坑機(jī)鉆頭自動(dòng)進(jìn)給運(yùn)動(dòng)，但若采用閉合螺母與絲杠配合形式，需要?jiǎng)恿敵鲚S反轉(zhuǎn)才能完成鉆頭的回程運(yùn)動(dòng)。但挖坑機(jī)動(dòng)力源是汽油機(jī)，其動(dòng)力輸出軸不能反轉(zhuǎn)，故采用閉合螺母與絲杠配合的進(jìn)給運(yùn)動(dòng)形式無法用于實(shí)際的挖坑作業(yè)。因此，本文采用開合螺母式自動(dòng)進(jìn)給機(jī)構(gòu)，當(dāng)螺母閉合時(shí)，挖坑機(jī)鉆頭完成進(jìn)給運(yùn)動(dòng)；挖坑作業(yè)完成后，打開開合螺母，手動(dòng)提起鉆頭至初始位置，完成回程運(yùn)動(dòng)。該方案既實(shí)現(xiàn)了挖坑作業(yè)的自動(dòng)化，又能迅速完成回程運(yùn)動(dòng)。

本文借鑒汽車輪胎平衡機(jī)快速鎖緊螺母機(jī)構(gòu)進(jìn)行開合螺母結(jié)構(gòu)設(shè)計(jì)，如圖2a所示。半螺母上有2個(gè)銷釘孔，分別裝有定銷和動(dòng)銷。定銷和基座固聯(lián)，半螺母可繞定銷轉(zhuǎn)動(dòng)。螺母撥片上有2種類型的4個(gè)軌道呈對(duì)稱分布，定銷在圓軌道內(nèi)滑動(dòng)，動(dòng)銷在直軌道內(nèi)滑動(dòng)。螺母撥片繞定銷轉(zhuǎn)動(dòng)時(shí)帶動(dòng)動(dòng)銷在直軌道內(nèi)滑動(dòng)，從而控制螺母開閉。螺母撥片和基座之間設(shè)置有彈簧，保證螺母一直處于閉合狀態(tài)。開合螺母中心點(diǎn)記為點(diǎn)，其中任意一個(gè)定銷位置記為點(diǎn)，動(dòng)銷所在滑道末端位置記為點(diǎn)，動(dòng)銷在滑道內(nèi)的位置記為點(diǎn)，螺母開合運(yùn)動(dòng)簡圖如圖2b所示。

a. 開合螺母結(jié)構(gòu)示意圖a. Half nuts structure diagramb. 螺母開合運(yùn)動(dòng)簡化示意圖b. Schematic diagram of nuts opening and closing movement

c. 螺母開合運(yùn)動(dòng)分析圖

c. Analysis of nuts opening and closing motion

1.螺母撥片 2.定銷 3.半螺母 4.動(dòng)銷 5.基座

1.Nut picks 2.Fixed pin 3.Half nut 4.Movable pin 5.Base

注：為桿的擺動(dòng)角，(°)；為桿的擺動(dòng)角，(°)；為動(dòng)銷軌道角，(°)；1為點(diǎn)與點(diǎn)之間的長度，m；2為點(diǎn)與點(diǎn)之間的長度，m；3為點(diǎn)與點(diǎn)之間的長度，m；4為點(diǎn)與點(diǎn)之間的長度，m；1為桿與水平線的夾角，(°)；2為桿與水平線的夾角，(°)；3為桿與水平線的夾角，(°)。

Note:is the swing angle of rod, (°);is the swing angle of rod, (°);is the orbit angle of movable pin, (°);1is the distance between pointand point, m;2is the distance between pointand point, (m);3is the distance between pointand point, m;4is the distance between pointand point, m;1is the angle between rodand horizontal level, (°);2is the angle between rodand horizontal level, (°);3is the angle between rodand horizontal level, (°).

圖2 開合螺母機(jī)構(gòu)運(yùn)動(dòng)分析圖

Fig.2 Movement analysis chart of half nut mechanism

利用解析法對(duì)半螺母的開合運(yùn)動(dòng)進(jìn)行運(yùn)動(dòng)分析，建立如圖2c所示的直角坐標(biāo)系。各桿件組成了一個(gè)封閉的矢量多邊形，即。在此封閉矢量多邊形中，各矢量和等于0，即滿足

式中1為點(diǎn)至點(diǎn)的方向向量；2為點(diǎn)至點(diǎn)的方向向量；3為點(diǎn)至點(diǎn)的方向向量；4為點(diǎn)至點(diǎn)的方向向量。

將封閉矢量方程（4）改寫并表示為復(fù)數(shù)矢量形式為

式中1為點(diǎn)與點(diǎn)之間的長度，m；2為點(diǎn)與點(diǎn)之間的長度，m；3為點(diǎn)與點(diǎn)之間的長度，m；4為點(diǎn)與點(diǎn)之間的長度，m；1為桿與水平線的夾角，(°)；2為桿與水平線的夾角，(°)；3為桿與水平線的夾角，(°)。

式中為動(dòng)銷軌道角，(°)。

由幾何關(guān)系知1=3=4，消去未知量2后，將1從0°取到60°，間隔5°，動(dòng)銷軌道角從90°取到120°，間隔5°，代入式（7）得3。由各桿件的桿長關(guān)系和初始位置角度（1=60°，3=120°），可知桿轉(zhuǎn)動(dòng)角為=60°?1，桿轉(zhuǎn)動(dòng)角為=120°?3。列出不同和組合下的值，如表1所示。

表1 動(dòng)銷軌道角和桿AE轉(zhuǎn)動(dòng)角對(duì)桿BF轉(zhuǎn)動(dòng)角的影響

表1中桿轉(zhuǎn)動(dòng)角的變化趨勢(shì)為：在動(dòng)銷軌道角不變時(shí)桿轉(zhuǎn)動(dòng)角隨桿轉(zhuǎn)動(dòng)角增大而增大，在桿轉(zhuǎn)動(dòng)角不變時(shí)桿3轉(zhuǎn)動(dòng)角隨動(dòng)銷軌道角增大而增大。從工作效率看，相同的桿轉(zhuǎn)動(dòng)角對(duì)應(yīng)的桿轉(zhuǎn)動(dòng)角越大螺母開合的效率就越高。從結(jié)構(gòu)尺寸看，桿轉(zhuǎn)動(dòng)角越大開合螺母機(jī)構(gòu)整體尺寸越大。即，桿轉(zhuǎn)動(dòng)角越大，螺母開合的效率就越高，但桿轉(zhuǎn)動(dòng)角變大時(shí)開合螺母機(jī)構(gòu)的整體尺寸就會(huì)變大。綜合考慮開合螺母的工作效率和結(jié)構(gòu)尺寸，取動(dòng)銷軌道角為105°。

1.3 手提式挖坑機(jī)整體結(jié)構(gòu)設(shè)計(jì)

該手提式挖坑機(jī)結(jié)構(gòu)如圖3所示，主要由機(jī)架、汽油機(jī)、帶輪、開合螺母、支撐架、絲杠、導(dǎo)軌和鉆頭等組成。汽油機(jī)動(dòng)力在其輸出軸處分為兩部分：一部分傳遞給鉆頭，帶動(dòng)鉆頭轉(zhuǎn)動(dòng)；另一部分經(jīng)帶輪傳遞到開合螺母，開合螺母與絲杠形成螺旋副，帶動(dòng)鉆頭實(shí)現(xiàn)進(jìn)給運(yùn)動(dòng)。在挖坑作業(yè)完成后，停止汽油機(jī)工作，通過螺母撥片打開開合螺母，將支撐架連同汽油機(jī)及鉆頭提起到初始位置，然后閉合開合螺母以備下次作業(yè)。

2 試驗(yàn)與分析

本文采用北京新宇航世紀(jì)科技有限公司JN338-100A型扭矩儀實(shí)時(shí)測(cè)量挖坑機(jī)作業(yè)過程中鉆頭轉(zhuǎn)速和扭矩。

2.1 試驗(yàn)裝置

試驗(yàn)裝置如圖4a所示，汽油機(jī)動(dòng)力輸出軸通過聯(lián)軸器與扭矩儀的一端相連，扭矩儀的另一端通過聯(lián)軸器與鉆頭聯(lián)接軸相連[32-33]。圖4b為試驗(yàn)現(xiàn)場(chǎng)。

2.2 試驗(yàn)方法

試驗(yàn)時(shí)間為2016年5月6日至8日，選擇華中農(nóng)業(yè)大學(xué)現(xiàn)代農(nóng)業(yè)科技試驗(yàn)基地平整地塊作為試驗(yàn)區(qū)域，試驗(yàn)過程中空氣濕度基本一致，試驗(yàn)前首先測(cè)定試驗(yàn)區(qū)域的土壤堅(jiān)實(shí)度。在試驗(yàn)區(qū)域均布取4個(gè)測(cè)試點(diǎn)，分別測(cè)量每個(gè)測(cè)試點(diǎn)在不同深度處的土壤堅(jiān)實(shí)度，測(cè)量結(jié)果見表2。由表2可知，土壤堅(jiān)實(shí)度在土層深度變化時(shí)基本保持不變，排除了土壤堅(jiān)實(shí)度變化對(duì)挖坑機(jī)作業(yè)中鉆頭消耗功率的影響。

為分析不同進(jìn)給量對(duì)挖坑作業(yè)過程中鉆頭扭矩變化的影響，選用Tr24×3、Tr24×5和Tr24×8 3種不同螺距的自動(dòng)進(jìn)給機(jī)構(gòu)進(jìn)行挖坑作業(yè)對(duì)比試驗(yàn)。試驗(yàn)過程中保證挖坑機(jī)鉆頭勻速工作。

表2 各測(cè)點(diǎn)土壤堅(jiān)實(shí)度

2.3 試驗(yàn)數(shù)據(jù)處理與分析

扭矩儀數(shù)據(jù)采集卡采集到的數(shù)據(jù)為各測(cè)點(diǎn)對(duì)應(yīng)的鉆頭轉(zhuǎn)速、鉆頭扭矩，進(jìn)而計(jì)算出各測(cè)點(diǎn)對(duì)應(yīng)的鉆頭位移。而后將各組數(shù)據(jù)按時(shí)長為1 s分段，計(jì)算出扭矩標(biāo)準(zhǔn)差，各組數(shù)據(jù)見圖5、圖6和圖7。

a. 測(cè)點(diǎn)1

a. Test point 1

b. 測(cè)點(diǎn)2

b. Test point 2

c. 測(cè)點(diǎn)3

c. Test point 3

a. 測(cè)點(diǎn)1

a. Test point 1

b. 測(cè)點(diǎn)2

b. Test point 2

c. 測(cè)點(diǎn)3

c. Test point 3

由圖5、圖6和圖7可知，在鉆頭速度恒定的前提下，3種試驗(yàn)條件挖坑作業(yè)過程中，鉆頭扭矩均隨時(shí)間增加呈上升趨勢(shì)。

對(duì)比分析圖5、圖6和圖7可知：1）螺距為8 mm各測(cè)點(diǎn)鉆頭扭矩均比螺距為3和5 mm大，且波動(dòng)幅度大。螺距為8 mm時(shí)，鉆頭對(duì)應(yīng)的進(jìn)給量8大于5.3 mm/r，土壤垂直運(yùn)動(dòng)速度小于鉆頭堵塞臨界速度，挖坑機(jī)鉆頭發(fā)生堵塞，所以扭矩增加且波動(dòng)幅度增大；2）螺距為3和5 mm時(shí)，對(duì)應(yīng)的進(jìn)給量分別為3和5 mm/r，均小于5.3 mm/r，土壤垂直速度大于鉆頭堵塞臨界速度，挖坑機(jī)能夠正常升運(yùn)土壤，因此二者各測(cè)點(diǎn)鉆頭扭矩和波動(dòng)幅度均相對(duì)較小。但是當(dāng)鉆頭進(jìn)給量滿足順利升土條件時(shí)，進(jìn)給量越大，挖坑效率越高，因此開合螺母螺距為5 mm時(shí)，不僅可以滿足正常升運(yùn)土壤，而且工作效率最高。

a. 測(cè)點(diǎn)1

a. Test point 1

b. 測(cè)點(diǎn)2

b. Test point 2

c. 測(cè)點(diǎn)3

c. Test point 3

此外，挖坑作業(yè)時(shí)，閉合開合螺母，開合螺母與絲杠形成螺旋副，帶動(dòng)鉆頭實(shí)現(xiàn)進(jìn)給運(yùn)動(dòng)；挖坑作業(yè)完成后，手動(dòng)打開開合螺母，通過提起開合螺母，能夠?qū)@頭順利提升至初始位置，從而完成鉆頭的回程運(yùn)動(dòng)，以備進(jìn)行下一個(gè)挖坑作業(yè)。整個(gè)試驗(yàn)過程中，開合螺母機(jī)構(gòu)工作性能均可靠。

3 結(jié) 論

1）設(shè)計(jì)了一種手提式挖坑機(jī)開合螺母式自動(dòng)進(jìn)給機(jī)構(gòu)，不僅實(shí)現(xiàn)了挖坑作業(yè)的自動(dòng)化，而且能迅速完成回程運(yùn)動(dòng)。該手提式挖坑機(jī)設(shè)計(jì)有支撐結(jié)構(gòu)，不僅能夠保證挖坑的垂直度，而且增強(qiáng)了安全性和可靠性。

2）運(yùn)用經(jīng)典挖坑理論，明確了挖坑機(jī)鉆頭進(jìn)給量對(duì)其升土效果的影響關(guān)系，并通過試驗(yàn)進(jìn)行了驗(yàn)證，為挖坑機(jī)進(jìn)給量的設(shè)計(jì)提供了參考。研究表明，開合螺母螺距為5 mm時(shí)，挖坑機(jī)扭矩及其波動(dòng)幅度均較小、工作效率最高。

3）采用解析法分析了開合螺母機(jī)構(gòu)的運(yùn)動(dòng)特性，確定出了其動(dòng)銷軌道角為105°。

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Design and experiment of automatic feed mechanism with half nuts structure of portable digging machine

Ma Li’na, Wang Jingliang, Zong Wangyuan※, Huang Xiaomao, Feng Jun

(430070,)

Digging machine is a kind of digging and tillage machine. Because its structure is simple and it can be operated conveniently, it is widely used as a hole digger. There are mainly 4 types of digging machines, i.e. suspension type, portable type, traction type and self-propelled type. On the mountains, hills, ravines and other complex terrain conditions, portable type of digging machine is popularly used to dig a hole so as to plant or transplant trees. Hence, this paper designed a new portable digging machine with a half-nut mechanism to keep the feed rate stable and decrease the torque of the drilling bit as far as possible when drilling the hole. In addition, the support structure was also designed for the digging machine for the sake of guaranteeing the verticality of the hole and ensuring the reliability and stability of the digging machine, as well as making the structure more secure. The feed rate of the digging machine was an important factor, which affected the torque and work efficiency of the drilling bit greatly. Research on the effect of the feed rate on the dynamic mechanical parameters of digging machine was of great significance for developing a new model of digging machine. However, the power of the digging machine was gasoline engine, so the power output shaft could not reversely rotate, and it could not be used for actual digging. Thus there was a great need to design a new structure that could solve the gasoline engine’s problem of rotating only in one direction. Accordingly, the half-nut mechanism was designed. According to the working principle of the half-nut, the motion characteristics of half-nut mechanism were analyzed by using the analytic method. The straight track angle of half-nut picks was decided as 105°, and thus a portable digging machine with half-nut mechanism was designed. The new designed digging machine could not only realize the digging operation automatically, but also complete the return movement rapidly. Then based on the working principle of digging machine, the relationship between the feed rate and the effect of lifting soil was studied. In order to verify the result, the experiment of testing the torque and rotational speed during the process of drilling a hole was conducted by using the torque measuring device JN338-100A made by Beijing Xinyuhang Century Science and Technology Co., Ltd. to collect the data afterward. Therefore it successfully provided a theoretical basis for the determination of feed rate of a new type of digging machine. It showed that when the pitch of half nut was taken as 3 or 5 mm, the torque and its fluctuation both were small. However when the pitch of half nut was taken as 8 mm, for it did not satisfy the working principle of digging machine, the torque and its fluctuation varied greatly, and the digging machine could not lift soil smoothly. In order to improve the work efficiency, the pitch of half nut was taken as 5 mm for this new designed digging mechanism finally. This paper provides a theoretical basis for the design of automatic feed mechanism of a new portable digging machine.

mechanization; design; soils; digging machine; half nuts; feed automatically; feed rate; torque

10.11975/j.issn.1002-6819.2017.04.004

S776.26+2

A

1002-6819(2017)-04-0025-07

2016-06-06

2017-02-05

公益性行業(yè)（農(nóng)業(yè)）科研專項(xiàng)經(jīng)費(fèi)(201203047)

馬麗娜，女，講師，山東萊蕪人，主要從事農(nóng)業(yè)裝備數(shù)字化設(shè)計(jì)技術(shù)研究。武漢 華中農(nóng)業(yè)大學(xué)工學(xué)院，430070。Email：sunnylina@163.com

宗望遠(yuǎn)，男，河南周口人，教授，博士生導(dǎo)師，主要從事現(xiàn)代農(nóng)業(yè)裝備設(shè)計(jì)與測(cè)控技術(shù)研究。武漢 華中農(nóng)業(yè)大學(xué)工學(xué)院，430070。 Email：zongwangyuan@mail.hzau.edu.cn

馬麗娜，王警梁，宗望遠(yuǎn)，黃小毛，馮 軍. 手提式挖坑機(jī)開合螺母式自動(dòng)進(jìn)給機(jī)構(gòu)的設(shè)計(jì)與試驗(yàn)[J]. 農(nóng)業(yè)工程學(xué)報(bào)，2017，33(4)：25－31. doi：10.11975/j.issn.1002-6819.2017.04.004 http://www.tcsae.org

Ma Li’na, Wang Jingliang, Zong Wangyuan, Huang Xiaomao, Feng Jun. Design and experiment of automatic feed mechanism with half nuts structure of portable digging machine[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2017, 33(4): 25－31. (in Chinese with English abstract) doi：10.11975/j.issn.1002-6819.2017.04.004 http://www.tcsae.org