SCREEN SHAKER Russian patent published in 2006 - IPC B07B1/40 B07B1/42 

FIELD: petroleum industry; natural gas industry; production of devices for drilling mud fluid cleaning.

SUBSTANCE: the invention is pertaining to the field of petroleum industry and natural gas industry, in particular, to production of devices for drilling mud fluid cleaning. The screen shaker consists of: a base; a frame mounted with the help of dampers; screen plates fixed on the frame; a device of changing a tilt angle of the frame; a feeding chute; a vibroexciter made at least out of two electromagnets mounted on each side of the frame. The stators of the electromagnets are fixed rigidly to the frame and their armatures are fixed to the frame through springs, stiffness of which together with stiffness of the dampers in a direction of a vector of the vibrations of the frame and the mass of the frame are defined by the following ratio C·k + Ca ·n/M = ω² , where C is stiffness of a spring of one electromagnet, in H/m; m is a quantity of the electromagnets, in pieces; Ca is stiffness of one damper, in H/m; n is a quantity of dampers, in pieces; M is the mass of the frame, in kg; ω is a resonance angular frequency of the frame vibrations, in radians/s. On the frame there is a vibrations sensor, output of which is connected to the device of control over the electromagnets (COEM) containing the sensor signals processing unit, which is generating unipolar control pulses, a pulses intensifier with a capability of adjustment of an amplification factor and an automatic keeping of the preset amplitudes of the pulses at the output. The windings of the electromagnets are connected to the COEM output. At that the COEM has a capability of operation in two modes: at the screen shaker starting operation - the mode of generation of the current pulses to feed the electromagnets at the capability to adjust of the frequency of the pulses sequence; during the screen shaker operation - the mode, when the automatic control device is processing the signals from the sensors and generating the unipolar current pulses for feeding the electromagnets and having a capability to change the amplitudes of the current pulses. The technical result is an increase of the screen shaker frame vibration acceleration with a capability to adjust the vibration acceleration directly during the screen shaker operation.

EFFECT: the invention ensures an increase of the screen shaker frame vibration acceleration with a capability to adjust the vibration acceleration directly during the screen shaker operation.

2 dwg, 2 ex