SU912919A1 - Rate-of-drilling meter - Google Patents

Description

one

The invention relates to drilling process instrumentation and can be used on drilling machines of various types.

Mechanical drilling velocity meters are known, whose operation is based on converting the transducer ioro of the movement of the drilling machine feed mechanism into rotary, whose speed is measured using a tachogenerator.

The disadvantage of such devices is the presence in the kinematic connection of the sensor with the feed mechanism of the step-up gear with a large gear ratio (reduction ratio), which leads to large drive forces, complicates the design of the sensor and reduces the reliability of the instrument.

The closest to the present invention is a mechanical drilling speed gauge, the action of which is based on the differentiation of an electrical voltage proportional to the magnitude of the deepening of the drill string. It contains a penetration sensor and remote control & laziness. The penetration sensor is a linear characteristic potentiometer mechanically connected to the spindle of the drilling machine in such a way that in one move of the spindle the moving contact of the potentiometer makes one turn within

10 working sector. The potentiometer is powered by a constant stabilized voltage source. The output voltage of the potentiometer is applied to a capacitor, the charge current of which

15 is proportional to the rate of change of voltage (voltage differential) and, therefore, to the mechanical drilling rate. The current in the capacitor charge circuit (differentiation circuit; controlled by a micro ammeter, the scale of which is calibrated in units of mechanical drilling speed.

3912919

The advantage of such a mechanical drilling speed gauge is the simplicity of the device, the absence of a step-down reduction gear in the sensor drive and, consequently, large efforts, which leads to high reliability of the instrument 1

However, the limited movement of the moving contact of the sensor potentiometer imposes a limit on O

the sensitivity of the device when increasing the spindle stroke makes it almost impossible to use the device with spindleless feeding of drilling tools. Indeed, the greater the stroke of the spindle (controlled drill hole deepening), the slower the output voltage of the sensor varies with a constant mechanical drilling speed, and the more sensitive the instrument must have.

The purpose of the invention is to eliminate the dependence of the sensitivity of the device on the magnitude of the controlled recess 25, which makes it possible either to increase the sensitivity of the device or to increase the limits of the value of the controlled recess of the drill string.

This goal is achieved by the fact that the device sensor contains two identical potentiometric sensors of cyclic action, switches, a resistor and a two-circuit electric circuit of differentiation, on jj

the inputs of which are connected to potentiometric sensors, and to its outputs alternately, through each half-cycle of sensor operation, a microammeter or its equivalent resistor is connected up to using a switch that is mechanically connected to the sensors, and the sensors are connected to a DC source.

The moving contacts of both sensors have the possibility of circular rotation mechanically connected with each other with a shift of 180 ° and connected with the feed mechanism of the drilling machine.

The output voltage from the sensor is supplied to two identical condensates, forming two identical independent differentiation circuits. The capacitor reverse current, proportional to the mechanical speed of the drill, is controlled alternately by one microammeter, which is included in one or the other differentiation circuit during the turn of the moving contact. 180 ° relevant potentiometer within the working sector. When deflecting a microammeter instead of it, the differential circuit turns on an equivalent resistor. Such periodic switching of the microammeter and the equivalent resistor is performed automatically by a switch mechanically connected to the moving contacts of the sensors.

The switching time determined by the response time of the switch is very short, so the switching process hardly reflects on the readings of the microammeter.

FIG. 1 shows a diagram of the device sensor design; in fig. 2 - Electrical circuit diagram of the meter.

The movable contacts of the sensors 1 with a mutual offset of 180 ° are rigidly connected to the shaft 2, which, when the feed mechanism of the rough machine is moving, rotates by means of a transmission mechanism. A profiled disk 3 controlling the operation of the switch k is fixed on the same shaft. The disk has such a shape and is oriented in such a way that switching takes place every half a turn of the shaft at the moment when the moving contact of one of the sensors approaches the end of the working sector.

The potentiometers R and R of the sensors (D) are powered from a source of constant constant voltage (V g) mounted in the instrument control panel (R). The output voltage from the sensors is supplied to the measuring circuit of the device, where C and C., differentiating capacitors; // d showing a microammeter, the scale of which is calibrated in units of mechanical drilling rate; a variable resistor used to calibrate the device; C is a damping capacitor smoothing the oscillation of the microammeter; In to the semiconductor diode protecting the microammeter against overload during idle fast movement of the feed mechanism; Into the diode that protects the microammeter from countercurrents when the feed mechanism moves up ;, VL is the equivalent resistance of the microammeter, P / t and 5 is a switch,

Claims (1)

Claim 912919 6 limits for measuring the magnitude of the recess, it is equipped with an additional potentiometric sensor, switch, resistor, and a second differentiation circuit, the inputs of which are connected to potentiometric sensors, and its outputs are alternately connected in one cycle · · using a switch to a microammeter, and in the other to a resistor, the switch being mechanically connected to the sensors. A mechanical drilling speed meter containing a potentiometric sensor, an electric differentiation circuit, a direct current source and a microammeter, are distinguished by the aim of increasing the sensitivity of and Sources.information taken into account during the examination 1. Leontiev 0.Proytman P.M. Monitoring and regulation of the mode of “on · core drilling. M., Nedra, 1972, 70-72. Figure 2