Motobur

One of the first patents for a manual drive and control drilling rig was granted on May 13, 1890 to Mr. John R. Lamb of the USA for his Post Hole Boring Machines ^[1] . It was a prototype of a hand drill, on which the rotation of the drilling tool was carried out due to the physical strength of the operator. And the first motor drills began to appear on construction sites much later. Along with the advent of light and compact two-stroke engines on the market, the idea was born to create a mechanism for drilling with a drilling tool driven by a gasoline engine, which is controlled by two people and which can be freely moved and drilled where it is impossible to go on a stationary drilling rig. The first hand-driven motor drills operated by two operators were heavy. Their weight was within 55 kg. The main weight fell on a large-sized worm gearbox and its body, which at that time was cast from steel . Light alloys were then not available for widespread use. Nevertheless, manual motorized drills operated by two operators began to be widely used, as the demand for a cheap drilling mechanism for general construction work was very high. And at the end of the fifties, when light alloys based on aluminum became widespread, the weight of a hand motor drill was almost halved. This was possible due to the manufacture of a motor-drill gearbox made of light alloys, as well as the reduction of gearbox sizes due to the use of the latest numerically controlled machine tools for gearboxes. In the early nineties, small-sized hydraulic components began to appear on the world market ( hydraulic pump , hydraulic motor , hydraulic distributor ), which manufacturers of manual motor drills began to install as a power drive for manual motor drills.

• Auger drilling in soft soils of the 1st, 2nd, 3rd and partially 4th categories
• Auger drilling to a depth of 10 meters, depending on the power and torque of the motor drill
• Auger drilling with a diameter of up to 500 mm depending on the power and torque of the motor drill
• Installation of fences and barriers of various types
• Installation of the column foundation
• Foundation strengthening
• Installation of heat exchangers
• Installation of communication lines and lighting poles
• Shoreline strengthening
• Strengthening sheet pits in shallow pits in loose soil with sheet pile piles
• Installation of lightning rods
• Geological survey

• Engine power - from 1.3 to 21 l / s
• Torque - from 75 to 1200 Nm
• Weight - from 7 to 250 kg
• Type of drilling transmission - mechanical or hydraulic
• Drilling depth - to 10 meters
• Drilling diameter - up to 500 mm

• Easy management does not require special training
• Low weight
• High mobility
• Low price
• Quick payback
• Cheap drilling tools

The main elements of a manual motor drill are the engine and the drilling transmission, which increases the torque provided by the engine and reduces the engine speed to acceptable for drilling. In manual motor drills with a mechanical drive, worm or cylindrical (coaxial) reduction gears are used as part of the drilling transmission . A centrifugal clutch is installed between the input shaft of the gearbox and the motor shaft, which allows the gasoline engine to transmit rotation through the gearbox to the drill auger when it reaches maximum speed. The main disadvantage of the mechanical drive is the large number of mechanical parts that are heavily loaded during drilling and are subject to increased wear due to this. In hydraulic hand drills, a simple hydraulic system is used consisting of a hydraulic pump and a hydraulic motor. The hydraulic pump creates oil pressure in the hydraulic system, which rotates the hydraulic motor with the drilling tool installed. The hydraulic distributor is responsible for the direction of rotation of the hydraulic motor and is equipped with a safety valve that relieves excess oil pressure in case of possible overload. The load on the hydraulic components during drilling is several times less compared to a similar mechanical gearbox. An important technical characteristic of any motor drill is the torque that the drilling transmission produces. The higher the torque, the easier the drilling process. This is especially noticeable when drilling soils above the second category. The main disadvantage of manual motor drills is the back impact that occurs during drilling, when the drilling tool sticks in the hole and the inertia of rotation of the drilling tool is instantly transmitted to the controls of the motor drill. This is a dangerous enough moment for operators when drilling, which can be harmful to their health. To prevent a kickback, some hand motor drills have special mechanical protection or are structurally designed so that the kickback is suppressed by the design of the motor drill frame and could not cause any harm to the operator.

Screw drills with a spiral (flange) are used as a drilling tool in manual motor drills, along which the excavated soil, destroyed by the cutting knives of the drill auger, rises to the surface. Very rarely, core drilling tools are used when drilling with manual motor drills. Sometimes during geological sampling of soil, hand-held augers install tools for sampling. Depending on the type of soil and the season of use, various types of cutting knives that facilitate drilling under different drilling conditions are installed on the augers. The auger method of drilling using a motor drill is designed to develop soft soils of categories 1, 2, 3 and partially soils of category 4 (depending on development conditions and the motor drill used). ^[2] .

A set of drilling tools ^[3] was specially developed for Antarctic research to extract ice core from a depth of 5 meters. This kit was used in conjunction with three different motor drills by the J. Craig Venter Institute of America in research in Antarctica in 2009.

1. A light manual motor-drill with a mechanical drive controlled by one person - this is a manual motor-drill with a weight of up to 11 kg with an engine power of up to 3.5 l / s and low torque of up to 150 Nm. The back impact that occurs during drilling is not very strong, so one person can control the motor drill. Categories of the cultivated soil 1st, 2nd. On the basis of light mechanical motor drills, motorized ice drills are made for fishing , equipped with special drilling augers for ice drilling.

There are also universal lightweight motor drills with the ability to separately control one or two operators. The special design of the handles, specially created for inexperienced users, allows without loss of convenience, to control the motor-drill for one person, and if necessary, use the help of a second person. This is especially important when drilling rocky soil, where a back impact can be quite strong and dangerous.

2. Manual motor drill with a mechanical drive controlled by two people (operators) - a tool weighing from 12 to 30 kg, engine power from 3.5 to 7 l / s, torque up to 300 Nm. The weight of the motor drill is large, the rotational speed of the drilling tool is high and the back impact is strong enough, therefore, two operators control it. Categories of cultivated soil 1st, 2nd, partially 3rd.

3. A heavy manual one-man motorized drill with a mechanical drive - a manual drilling rig with a mechanical drive, engine power from 5 to 8 l / s, torque up to 350 Nm and weight up to 80 kg. Structurally, the motor drill is made in the form of two blocks, an engine and drive handles, which are interconnected by a jet rod that completely extinguishes a back strike. The main drawback of all motor drills for the two operators - the back strike - is completely defeated. Categories of cultivated soil 1st, 2nd, partially 3rd.

4. A manual motorized drill with a hydraulic drive controlled by two operators - a manual drilling rig consisting of two blocks. The first block is a hydraulic station weighing 30 kg, the second block of the control handle with a hydraulic motor weighing 15 kg. The weight of the control levers is lower than the equivalent power of the weight of a mechanical motor drill, but the torque reaches 500 Nm, so two people are required to control it. Back impact is low due to the small working revolutions of the drilling tool. Categories of cultivated soil 1st, 2nd, partially 3rd.

5. Manual motorized drill with hydraulic drive controlled by one person - a manual drilling rig with a capacity of 7 to 15 l / s, a torque of up to 1200 Nm and a weight of up to 245 kg. The drilling rig consists of two blocks that are interconnected by a jet rod. Thanks to this, there is no back strike. There are also manual hydraulic motor drills made according to the principle of a children's rocking chair at one end, which houses the hydraulic station, and at the second end of the control handle. This design is also completely devoid of kickback. Categories of cultivated soil 1st, 2nd, 3rd, partially 4th.

Motor drills are used for scientific research when sampling soil and ice - LTER (Long-Term Research Network) for Arctic research ^[4] and for research in the Antarctic. ^[five]

NASA experts throughout the ICESCAPE research mission ^[6] to study the causes of melting polar ice in the Chukchi Sea used a light mechanical motobur.

In 2012, when testing a space suit for flights to Mars, developed by the University of North Dakota (UND, University of North Dakota) as a prototype of a space boring tool, a light mechanical motobur was used ^[7] .