RU181154U1 - Mechanical three-stage gearbox for low-power manual drilling rigs - Google Patents

Abstract

A mechanical three-stage gearbox for low-power manual drilling rigs, comprising a housing with a three-stage gear installed therein, the housing comprising holes for the input and output shafts of the three-stage gear. The three-stage transmission mechanism comprises an input gear shaft of the first stage, on which a gear is installed having an external arrangement of teeth and engaging with a gear mounted on the gear shaft of the second stage and having an internal arrangement of teeth, and a second gear is also installed on the gear shaft of the second stage a gear having an external arrangement of teeth and engaging with a gear mounted on a gear shaft of a third stage and having an external arrangement of teeth, moreover, on a gear shaft At the same stage, another gear is installed having an external arrangement of teeth and engaging with a gear of the output shaft of the gearbox, wherein the gear of the output shaft of the gearbox has an external arrangement of teeth. The technical result of the proposed utility model is to reduce the level of vibration and the effect of the reverse impact when working with a manual drilling rig by reducing the speed of rotation of the drill auger. 1 s.p. f-ly, 3 ill.

Description

Technical field

This utility model relates to mechanical engineering and can be used in all sectors of the national economy to change the angular velocities and torques of machine shafts and mechanisms, in particular, this utility model is intended for use in a manual installation for drilling soil (in a motor drill).

State of the art

The vast majority of low-power two-stroke engines used on hand tools with a gasoline engine have a counterclockwise rotation of the crankshaft. All the soil drilling augers produced on the world market have reverse right rotation in order to lift the earth from the hole to the surface. The torque of a low-power two-stroke engine is not more than 4 Nm. To drill the soil, it is necessary to increase the torque of the gasoline engine by several times and reduce the working maximum engine speed, which is equal to 8000 rpm.

At the moment, two-stage mechanical gearboxes are used for this, equipped with gears with an external arrangement of teeth (with external gearing), a gear ratio of 1:30, which reduce the rotation of the engine to 260 rpm and increase the torque transmitted from the engine to 120 Nm . Such characteristics provide the operator of a motor-drill with the opportunity to drill only light soils of category 1-2 (sandstone, sandy loam, loam). In addition, drilling at a speed of 260 per minute, quite dangerous for the driller. The high rotation speed of the drill auger causes strong vibrations during drilling and, if not used carefully, drillers can get shock injuries, dislocations and fractures caused by parts of a motor drill (manual drilling rig) if, for example, during operation, the drill auger suddenly gets stuck between stones in the ground. This dangerous effect is called a kickback.

To increase the torque of the engine and reduce the speed of rotation of the drill auger, you need to increase the gear ratio of the gearbox. To do this, you need to increase the size of the gear wheels of the gearbox (diameter and number of teeth) or add two more steps with gears. The number of steps added must be a multiple of two in order to maintain the right rotation (clockwise) of the drill auger.

In this case, the weight of the gearbox will increase several times and such a heavy gearbox will not be possible to use in a manual installation for drilling soil (in a motor drill), since one or two drillers simply will not be able to lift the motor drill together with the drill auger and soil that sticks and rises along the auger from the hole while drilling. Also, the price of a gearbox with four steps or more will be expensive and will significantly increase the cost of the final product and turn the hand tool into a stationary drilling rig, which requires a wheeled or tracked chassis to move.

The prior art various types of gearboxes designed to change the angular velocities and torques of the shafts of machines and mechanisms (see, for example, patent RU 2025626 C1, published 12/30/1994). In the known technical solution, the gear reducer comprises a housing consisting of plates having through holes and brackets with cantilever axles, on which gear blocks with external and internal gears are installed in the through holes of adjacent plates, and the cantilever axes are made eccentrically and can be rotated in the plane perpendicular to the axes of the blocks. In this case, the through holes and brackets of adjacent plates are oriented relative to each other so that the interaxal segments of the next steps intersect with the interaxal segments of the previous steps at angles, the value of which is determined by the corresponding ratio.

Consider the known device does not allow it to be used for manual drilling rigs, because it contains only two stages and, accordingly, will not provide the necessary torque at a low speed of rotation of the output shaft of the gearbox.

Utility Model Disclosure

The purpose of this utility model is to obtain a three-stage gearbox for manual drilling rigs while maintaining the right rotation of the gearbox output shaft.

The technical result of the proposed utility model is to reduce the level of vibration and the effect of the reverse impact when working with a manual drilling rig by reducing the speed of rotation of the drill auger.

The specified technical result is achieved by the fact that a mechanical three-stage gearbox for low-power manual drilling rigs, comprising a housing with a three-stage gear installed therein, the housing contains holes for the input and output shafts of the three-stage gear, the three-stage gear containing the input gear shaft the first stage, on which the gear is installed, having an external arrangement of the teeth and which engages with the gear installed on the gear shaft of the second stage and having an internal arrangement of teeth, and on the gear shaft of the second stage also has a second gear having an external arrangement of teeth and engaging with a gear mounted on the gear shaft of the third stage and having an external arrangement of teeth, moreover, on the shaft the gear of the third stage also has another gear having an external arrangement of the teeth and engaging with the gear of the output shaft of the gearbox, and the gear of the output shaft of the gearbox has an external location tooth laying.

A gear for locking the reverse rotation of the output shaft of the gearbox is installed on the gearbox housing, while the gear for locking the reverse rotation contains a ratchet wheel mounted on the input gear shaft of the first stage, and a lever movably mounted on the gearbox to lock the rotation of the ratchet wheel in one of the sides of rotation .

The ability to achieve the above technical result, namely, reducing the level of vibration and the effect of a reverse impact when working with a manual drilling rig, is provided by the presence of three stages in the gearbox, made in the above design, allowing to reduce rotation speed and increase torque, as well as by a rotation blocking mechanism, which, when the screw shaft is jammed, allows the unit to be brought into operation without vibration and the effect of a reverse impact.

Brief Description of the Drawings

In FIG. 1 shows a general view of the gearbox from above.

In FIG. 2 shows a general view of the gearbox from below.

In FIG. 3 is a sectional drawing of a gearbox.

Utility Model Implementation

The proposed gearbox is a three-stage. That is, only one step is added to the usual two-stage gearbox, but the right rotation (clockwise) of the drill auger is preserved. It was possible to do this by applying a gear wheel with an internal arrangement of teeth in the first gear stage. Thanks to the gear wheel with the internal arrangement of the teeth, the rotation of the remaining gears in the gearbox in the opposite direction changes, the compactness and low cost of the gearbox are maintained. The gear ratio of the gearbox increases almost five times, to 1: 143, the rotation speed decreases to 50 rpm, the torque increases to 500 Nm.

The result is a manual drilling rig safe for drillers as at such a low rotational speed, vibration, the effect of a return shock and the risk of shock injuries almost completely disappear. And the working capabilities of a manual drilling rig (motor drill), which can now drill holes in the soil up to 4 categories (heavy plastic clay with ASG) and even in frozen ground, are significantly increased. Also, the design of this gearbox provides for a reverse rotation lock, which allows you to unscrew the auger that has jammed during operation (between stones, between large plant roots) in the opposite direction from the hole.

The gearbox is used in manual drilling rigs, (motor drills) of light weight (up to 35 kg) and size, which are controlled only by the physical strength of a person, without additional mechanisms.

According to FIG. 3, the proposed gearbox consists of a housing (5), in which elements of the transmission mechanism are installed. The transmission mechanism is a three-stage gearbox, which includes: the gear shaft of the first stage (1) (this shaft is the input shaft, i.e. the shaft to which torque is supplied from the internal combustion engine), the gear shaft of the second stage (2 ), a third-stage pinion shaft (3), an output shaft (4) for driving the drill auger into rotation (a drill auger is connected to this shaft by means of an appropriate connection). A gear wheel (6) with an external arrangement of teeth is mounted on the gear shaft of the first stage (1). The gear (6) engages with the gear (7) of the second-stage gear shaft (2). Gear (7) is a gear with an internal arrangement of teeth and has a larger diameter than gear (6). Another gear (8) is also installed on the gear shaft of the second stage (2), which provides the transmission of torque to the gear shaft of the third stage (3), through the gear (9) installed on this shaft. Gear (9) has a larger diameter than gear (8). In this case, the gears (8) and (9) have an external tooth arrangement. Another gear (10) is also installed on the gear shaft of the third stage (3), which transmits torque from the gear shaft (3) to the output shaft (4) by means of an external gear (11) mounted on the output shaft (4) teeth. Moreover, the diameter of the gear (11) exceeds the diameter of the gear (10), which also has an external arrangement of the teeth.

The proposed gearbox also contains a mechanism for blocking the reverse rotation of the output shaft of the gearbox. At the same time, the reverse rotation locking mechanism comprises a ratchet wheel (13) mounted on the input gear shaft of the first stage (1), and a lever (12) movably mounted on the gearbox to block the rotation of the ratchet wheel (13) in one of the rotation sides .

Claims (2)

1. Mechanical three-stage gearbox for low-power manual drilling rigs, comprising a housing with a three-stage gear installed therein, the housing comprising holes for input and output shafts of a three-stage gear, characterized in that the three-stage gear contains an input gear shaft of the first stage on which a gear is installed having an external arrangement of the teeth and engages with a gear mounted on the gear shaft of the second stage and having the internal arrangement of the teeth, and on the shaft of the gear wheel of the second stage also has a second gear having an external arrangement of the teeth and engaged with the gear mounted on the gear shaft of the third stage and having an external arrangement of the teeth, and on the shaft of the gear of the third stage is also installed another gear having an external arrangement of the teeth and engaged with the gear of the output shaft of the gearbox, wherein the gear of the output shaft of the gearbox has an external arrangement of teeth. 2. The mechanical three-stage gearbox according to claim 1, characterized in that a gear for locking the reverse rotation of the output shaft of the gearbox is installed on the gear housing, while the locking mechanism for the reverse rotation contains a ratchet mounted on the input gear shaft of the first stage, and a lever movably mounted on the gear case to ensure that the ratchet wheel is locked in one of the sides of rotation.

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