SU1293369A1 - Pulse shaper - Google Patents

Abstract

The invention relates to a hydraulic jet control circuit. The purpose of the invention is to simplify the design and increase the steepness of the fronts of the generated pulses. The generator contains an inlet channel 1, a concave surface 3 with openings 4, and a control element 5 in the form of a ribbed cylinder, which, under the action of a jet from channel 1, moves along a curved partition, communicating the inlet channel 1 with the outlet 7. Radius of curvature of the surface 3, height and the number of edges of element 5 is controlled by the parameters of the generated pulses. 1 3. Clause f-ly, 1 ill. LNR.G and and fin (O (L g r to with co 00 05 co. Sr | G QS

Description

The invention relates to hydraulics and is intended for use in hydraulic jet chains both for power purposes and for control circuits.

The purpose of the invention is to simplify the generator design and increase the steepness of the fronts of the generated pulses.

The drawing shows the construction of a generator in various stages of its operation.

The generator contains an input channel 1, a housing 2, a drainage channel 3, made in the form of a surface with through-holes concave away from the input channel. The radius of curvature of the surface 3 in the zone of movement of the control element 5 is determined by the ratio

R ry + KiT,

where / is the radius of curvature of the surface, m;

ГУ - external radius of the control element, m;

/ С | - coefficient equal to. 0.32

T-pulse repetition period, p.

The drainage flow is diverted through the channels 6 of the housing. The working output channel 7 is installed in the center of the surface 3 inlet to the input channel 1. The control element 5 is made in the form of a ribbed cylinder, and the ribs on the surface of the control element are made, for example, in the form of isosceles triangular prisms having a height not larger than the diameter of the input channel Ah, and the number of edges is determined by

Pr Kcht, / 1 P "(in,

where Kch - coefficient equal to 40

Shu is the mass of the control element, kg;

P "is the pressure in the inlet channel. Pa;

diix - diameter of the inlet channel, m

In order to ensure the stability of the operation, the ribs on the surface of the control element must be made in the form of equidistantly located isosceles prisms, which ensures complete symmetry of the control element relative to the axis of rotation.

The flow of power Qn enters through the input channel 1 into the zone of interaction with the control element 5 formed by the drainage output channel 3 and the housing 2 of the generator.

When the input flow rate supply Qn is supplied in the form of a compact cylindrical jet, the latter takes control element 5 out of the initial steady state and causes it to move to the left (Fig. 1a). A regenerating force is then formed, tending to return the control element to its original state. This force is due to the curvature of the rolling surface and the force of interaction of the compact jet with the ribbed surface of the control element. As a result, element 5 moves to the right (Fig. 1b), opening in the leftmost position the working output channel 7, with the result that the maximum flow rate of the liquid appears at the output of the pulsator. Next, item 5 goes back to average.

position (Fig. 1c) and moves to the right. In the extreme right position (Fig. 1g), the output flow peak again forms at the output and the restoring force increases, tending to return the element 5 to the initial state. The process is then repeated (Fig. 1a) and is continuous. The oscillation energy of the control element 5 is maintained by the power of the input supply source Qn and depends on the ratio of these and influencing

on the parameters of self-oscillation factors.

The power of the generated hydraulic pulses is completely determined by the flow rate of the fluid in the inlet channel. The generator has a very high efficiency, if we consider the latter as the ratio of the power flow in the output channel to the power flow in the input channel.

In order to provide positive feedback and increase the steepness of the fronts of the generated pulses, ribs in the form of isosceles triangular prisms are applied on the lateral cylindrical surface of the control element. On the basis of obtaining a stable process of self-oscillations, an experimentally obtained dependence for the number of edges

 .

Less than the formula, the number of edges leads to instability of the process and to the fact that the ribbed cylinder, even with the calculated values of tu, Pvx, dex, does not roll

5 and self-oscillations either do not arise, or, having arisen, immediately fade out.

When the ribbed cylinder 5 rolls over the surface 3 in certain cases, its displacement relative to the output channel is possible. To eliminate this phenomenon

0 on the surface 3 are fixed, for example, guides connected to the surface, along which the ribbed cylinder rolls back and forth, which has special grooves in diameter for this purpose.

45

Claims (2)

1. A pulse generator comprising a housing, an input and output working and drainage channels and a control element, differing in that, in order to simplify the construction, the control element is designed as a ribbed cylinder, and the working output channel coaxial with the inlet channel is installed in the center of the drainage outlet channel made in the form of a surface with through holes on which placed with the possibility of reciprocating movement of the control element, and the radius of curvature of the concave surface in the zone of movement of the control element is determined by the ratio R ry + KiT ,, where / is the radius of curvature of the surface, m; ГУ - external radius of the control element, m; Ki is a coefficient equal to 0.32 Hz-repetition period generated hydraulic pulses 2. The generator according to claim 1, characterized in that in order to increase the steepness of the fronts of the gene pulses, the ribs on the surface of the control element are made in the form of isosceles triangular prisms having a height not larger than the diameter of the input channel, and the number of ribs Pr is determined by the ratio Pr K.zniylPv dex, where K.2 is a coefficient equal to 40 tons — the mass of the control element, kg; Rvh - pressure in the inlet channel. Pa; d (in - the diameter of the input channel, m