RU2307910C1 - Boring rig - Google Patents

Abstract

FIELD: mining, particularly devices for blast-hole drilling in excavation roof.

SUBSTANCE: drilling rig comprises slider movably installed on guiding column, rotator with drilling rod and feeding device having drive shaft kinematically connected with drilling rod and driven shaft provided with friction pulley. Flexible member connected to tightening device passes over friction pulley. Drive shaft of feeding device is hollow and has axial orifice. Rotator and feeding device are separate members, wherein rotator is installed in lower slider part and feeding device is located in upper part thereof so that drilling rod passes through drive shaft orifice.

EFFECT: increased drilling efficiency due to decreased power necessary for drilling rod rotation and reduced drilling crown blade wear.

3 cl, 2 dwg

Description

The invention relates to the mining industry, in particular to the designs of devices designed for drilling holes in the roof of the mine.

Known drill rig containing a guide column mounted on it movably in the longitudinal direction of the rotator with a feed drive, including a driving drum, on which a rope is wound, the end of which is connected to the column body and the kinematic coupling mechanism of the rope with the feed drive [1].

A disadvantage of the known device is that in the process of drilling, when winding the rope onto the “roll” drum, the diameter of the winding is arbitrarily changed, which means that the feed speed is arbitrarily changed, which leads to a violation of the drilling mode and breakage of the drilling tool.

The closest technical solution is a drilling rig containing a carriage mounted movably on a guide column, a rotator with a drill rod and a feed drive mounted on it, the drive shaft of which is kinematically connected to the drill rod, and a friction pulley mounted on the driven shaft, covered by a flexible element connected to tensioning device [2].

Drilling facilities made on the basis of this technical solution are characterized by a relatively stable pitch for each rotation of the drill rod. The design provides the ability to control this step depending on the characteristics of the rocks being drilled. The simple and compact design of the feeder can be successfully used to work in combination with the widely used hand drilling tools, such as mining electric and pneumatic drills, as well as pneumatic portable, core and telescopic perforated rotary hammers. The fact is that the pneumatic feeders currently used to feed the punchers constantly press the drill bit to the bottom of the hole, which contributes to its strong abrasive wear during rotation [3]. The use of the recommended feeder with a constant pitch allows you to hold the crown in the process of impact and subsequent rotation directly at the face of the hole without constant preload, which will significantly reduce the abrasive wear of its blade. This in turn will reduce the consumption of crowns and increase the average traveling speed of drilling.

Along with the indicated advantages, the above construction has a drawback, the essence of which is as follows.

The rotator of the drilling tool and the feed drive are almost a single functional element located in one housing. The spindle of the rotator into which the drill rod is inserted is at the same time the drive shaft of the worm gear reducer. Such a constructive solution can only be used for rotational drilling, without imposing shock loads on the feed drive.

The aim of the invention is to expand the scope by using drilling tools with various drilling methods, including rotary hammers.

This goal is achieved in that the feed drive shaft is hollow, with a hole along its axis, the rotator and feed drive are made separately, with the rotator installed in the lower and the feed drive in the upper part of the carriage so that the drill rod passes through the hole of the drive shaft.

Unlike the well-known in the recommended design of the drilling rig, the shock loads from the punch along the rod are transferred to the bottom without affecting the feed drive units. This makes it possible to use perforators with high impact power as a rotator.

Figure 1 shows a General view (schematic diagram) of the machine in its original position; figure 2 is a section aa in figure 1.

The drilling rig comprises an axially movable carriage 2 located on a guide column 1 and a rotator 3 mounted thereon (a rotary hammer) and a feed drive 4 (FIG. 1). The feed drive is a worm gear, the drive shaft of which is a hollow spindle 12, on the surface of which a worm is made, and in the upper part there is a drive clutch 13 (Figure 2). On the cantilever part of the driven shaft of the worm gear mounted friction pulley 6 (Figure 1). The drill rod 5 is passed through the sleeve 13, then through the axial hole in the spindle 12, and its end part is installed in the rotary axle of the drill. The rope 7 is mounted on the upper end of the guide column 1, it envelops the friction pulley 6 and is connected to a tension device, including a spring 8 and a handle 9, pivotally mounted in the lower part of the guide column 1. The handle 9 provides adjustment of the cable tension so that when the handle 9 is pressed down (in the direction of the arrow) the tension increases, and in the opposite direction, the cable tension weakens or is completely eliminated. The hammer drill 3 is mounted on the bracket 10 so that it rests on the elastic element 11, which reduces the intensity of the transmission of vibration to the machine structure. In the coupling 13, through which the drill rod 5 passes, an opening is made, the cross section of which is congruent to the profile of the drill rod, which ensures the transmission of torque. The bar passes freely through this hole. The coupling 13 can be connected kinematically with the spindle 12 in various ways, ensuring their mutual longitudinal mobility within, greater than the amplitude of the oscillations of the drill rod. Due to the wide variety of options for such a kinematic connection, including by means of elastic elements, they are not shown in the drawings.

The principle of operation and operation of the drilling rig are as follows.

In the initial position, before starting drilling, the carriage 2 with the perforator 3 is located in the lower part of the guide column 1, while the rope 7 is in a taut position. By turning on the perforator 3, the drill rod 5 is rotated, from which the torque through the drive sleeve 13 and the spindle – worm 12 (FIG. 2) is transmitted through the gearbox to the friction pulley 6. There is a synchronous rotation of the drill rod 5 and the friction pulley 6, but with different speed, different from each other by the gear ratio.

The rigid kinematic connection of the rod and the friction pulley 6 provides a constant feed pitch for each revolution of the drill rod. The rotation of the drill rod in rotary hammers occurs at the idle of the hammer, i.e. when the shock impulse does not pass through the bar. It is at this moment, when the rod is in a relatively "calm" state, and there is a mutual contact of the rod 5 and the drive clutch 13, i.e. torque impulse transmission. This is determined by the fact that the axial shock loads on the transmission of the worm gearbox are practically not transmitted. At the end of drilling by turning the handle 9, weaken the rope 7 and the punch 3 returns down.

Comparison of the recommended drilling rig with the base object, namely with the currently used telescopic rotary hammers, shows that the use of the recommended design provides increased drilling efficiency by reducing power costs when rotating the drill rod and reducing wear of the drill bit blades. This is achieved by eliminating the constant pressing them to the bottom of the hole, characteristic of the feed by means of a pneumatic cylinder. Numerous studies have found that the cost of power required to operate the feed mechanisms for percussive drilling methods for hard rock is approximately 5% of the total power of the drill [4]. This suggests that the power take-off from the drill rod used for the operation of the feed mechanism does not significantly affect the operation of the perforator.

Information sources

1. Karetnikov VN, Kleimenov VB, Nuzhdikhin A.G. Fastening of capital and preparatory mine workings. Reference book - M., Nedra, 1989 - p. 480-481.

2. RU 2256761 C1, 03/31/2004

3. Medvedev I.F. Drilling modes and selection of drilling machines. M., Nedra, 1975, pp. 175-177.

4. Alimov O.D., Dvornikov L.T. Drilling machines. M., Mechanical Engineering, 1976, p. 191.

Claims (3)

1. A drilling rig comprising a carriage mounted movably on a guide column, a rotator with a drill rod and a feed drive mounted on it, the drive shaft of which is kinematically connected to the drill rod, and a friction pulley is installed on the driven shaft, covered by a flexible element connected to the tensioner, characterized in that the drive shaft of the feed drive is made hollow, with a hole along its axis, the rotator and the feed drive are made separately, with the rotator installed in the lower and the feed drive in the upper part of the carriage, that the drill rod passes through the hole of the drive shaft. 2. The drilling rig according to claim 1, characterized in that the axial hole made in the drive shaft is provided with a section whose inner section is congruent to the cross-sectional profile of the drill rod. 3. The drilling rig according to claim 1, characterized in that a serial drilling tool (a mining drill, a perforator) is used as a rotator.

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