JPS5842022Y2 - Hopper for solid-liquid multiphase fluids - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a hopper that is equipped with an agitating blade that is rotationally driven by a hydraulic motor and is used for solid-liquid mixed phase liquids such as ready-mixed concrete and coal/petroleum slurry.

In this type of hopper, when high-concentration slurry such as fresh concrete is put into the hopper, an agitation blade is rotated by a hydraulic motor, and the slurry is agitated and mixed by the agitation blade and is successively sucked into a pump suction section, etc. be.

With this hopper, particles such as aggregate in the slurry may get caught in the gap between the stirring blade and the hopper wall, or particles may become bridged in the gap, causing excessive torque to act on the stirring blade. .

In such cases, with conventional systems, the pressure in the hydraulic circuit increases in proportion to the torque, pressure escapes from the safety relief valve, etc., and the stirring blade traps particles at that position, causing the torque to act. It just stops.

In general, cross-linking and entrapment of particles will not come off as long as force is applied continuously in the direction in which the force was applied; Otherwise, the only option is to reverse the stirring blade.

Therefore, conventionally, as a method for reversing the blade, an operator manually reverses the stirring blade in the forward and reverse directions and uses the impact to release the particles from being trapped.

Since such a situation often occurs during operation, the operator cannot leave the machine side of the hopper during that time.

This idea was proposed in view of the above circumstances, and when excessive torque is applied to the stirring blade due to cross-linking or entrapment of particles, this torque is detected and the forward/reverse rotation of the stirring blade is controlled. The object of the present invention is to provide a hopper in which bridging and jamming are automatically released.

An embodiment of this invention will be described below with reference to the drawings.

In FIGS. 1 and 2, reference numeral 1 denotes a hopper main body, and a shaft 2 that is rotationally driven by a hydraulic motor 6, which will be described later, is provided through the hopper body, and stirring blades 3, 3 are fixed to this shaft 2. There is.

When the stirring blades 3, 3 rotate, the hopper body 1
The shape and dimensions approach the inner wall of the building at a small distance.

A cylindrical suction port 4 is connected to the lower part of the hopper body 1,
Although not shown, a concrete pump is connected to the end.

Note that a screw 5 is provided at the suction port 4 to apply force to push the slurry into the pump.

The rotation of the rotating blade 3 is controlled in forward and reverse directions as shown in the flowchart shown in FIG.

In other words, when the shaft 2 normally rotates in the forward direction and rotational torque exceeding the set value is applied to the shaft 2 due to cross-linking or entrapment of particles,
Shaft 2 rotates in the opposite direction, and when this reverse rotation releases the jamming and bridging and the rotational torque falls below the set value,
After the set time, the motor rotates forward again to return to normal operation, and if the rotational torque still does not fall below the set value, it immediately changes to forward rotation again and repeats forward and reverse rotation until it falls below the set value. There is.

For example, the forward/reverse rotation control of the rotating blade 3 may be performed by
This is done as shown in the hydraulic system diagram in Figure 5 and the electrical circuit diagram in Figure 5.

In FIG. 4, the hydraulic motor 6 is capable of forward and reverse rotation, and rotational torque detection devices, that is, pressure switches PS1 and PS2 are provided before and after its connection, and a directional switching valve, for example, 4 points and 2 positions, is provided. It is connected to a pump 8 via a spring-offset solenoid valve 7.

In FIG. 5, relays CR1 and CR2 and a timer TR are provided which are activated by the pressure switch PS1, and a relay CR3 which is activated by the pressure switch PS2 is provided to control the excitation and demagnetization of the solenoid SQL of the solenoid valve 7. ing.

The effect will be explained below.

Normally, the port of the solenoid valve 7 is located at the position shown in FIG. 4, causing the hydraulic motor 6 to rotate in the forward direction, and the stirring blade 3 to rotate in the forward direction.

At this point, particles are entrapped and crosslinked, causing the stirring blade 3
If it stops moving, the oil pressure on the supply side to the hydraulic motor 6 will rise, and the pressure switch PS, which has been set to a certain pressure in advance, will rise.

Turn on.

At this time, in FIG. 5, coil 8 of relay CR1,
Coil 9 of relay CR2 and coil 10 of timer TR are excited.

First, the normally open contact 12 of the relay CR2 is turned ON, and the solenoid SQL is energized.

Therefore, by switching the port of the solenoid valve 7,
That is, pressure oil is supplied from the pressure switch PS2 side, and the hydraulic motor 6 is rotated in the reverse direction.

When the stirring blade 3 connected to the hydraulic motor 6 rotates in the opposite direction and the trapped particles are removed, the normally closed contact 13 of the timer TR is turned OFF after the set time has elapsed, so that the relay CR1 is activated. The self-holding is canceled (at this time, the pressure switch PS1 is on the return path to the oil tank, so it is naturally OFF), and the coil 9 of the relay CR2 is demagnetized, turning off the normally open contact 12.
and demagnetizes solenoid SQL.

Therefore, the port of the electromagnetic valve 7 returns to normal, the hydraulic motor 6 rotates in the normal direction, and the stirring blade 3 rotates in the normal direction.

In this way, particle entrapment and crosslinking are automatically released and normal operation is resumed.

In addition, in the above, when the jamming etc. are not released even if the reverse rotation is performed, the pressure on the pressure switch PS2 side rises above the set value and this pressure switch PS2 is turned ON.
The coil 14 of relay CR3 is energized, and this relay CR3
The normally closed contact 15 of is opened.

Then, the coil 9 of the relay CR2 is immediately demagnetized even if it is within the time set by the timer TR, its normally open contact 12 is opened, the solenoid SQL is demagnetized, and the port of the solenoid valve 7 is moved to the offset position shown in FIG. to be restored.

Therefore, the hydraulic motor 6 rotates in the normal direction again, causing the stirring blade 3 to rotate in the normal direction.

At this time, the pressure switch PS2 is on the return path to the oil tank, so it is turned off, the coil 14 of the relay CR3 is demagnetized, and its normally closed contact 13 is turned on, returning to the initial state.

If the jamming is still not released even after returning to normal rotation, the pressure switch PS□ is turned on and the rotation is reversed again.
In this way, the forward and reverse rotations are repeated alternately to release the jamming etc. by the impact, and after release, normal operation returns.

Note that in this embodiment, two pressure switches PS1
．． PS2 is installed to control forward and reverse rotation, but a single pressure switch detects excessive rotational torque in either forward or reverse rotation, and an electric switch is installed to control forward and reverse rotation based on this. A circuit may also be configured.

In addition, in order to detect excessive rotational torque applied to the shaft 2 of the stirring blade 3, a method such as detecting the rotational torque using a strain gauge attached to the shaft 2 may be used instead of using a pressure switch in the hydraulic system. can.

As explained above, the hopper of this invention is equipped with a rotational torque detection device that detects the rotational torque of the stirring blade, and the forward and reverse rotation of the stirring blade is controlled by the signal from this rotational torque detection device. Therefore, if particles such as aggregates become trapped or crosslinked in the gap between the inner wall of the hopper body and the stirring blade, the stirring blade will rotate in the opposite direction to release the jamming, or the forward and reverse rotation will be repeated. It is released by the impact.

In this way, since jamming etc. are automatically released and normal operation is restored, there is no need for the operator to constantly monitor the hopper machine, resulting in labor savings.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention; Fig. 1 is a cross-sectional view of the hopper, Fig. 2 is a cross-sectional view taken along the line II-II along the first axis, and Fig. 3 is a flowchart of forward and reverse rotation of the stirring blade. figure,
FIG. 4 is a hydraulic system diagram for driving a hydraulic motor, and FIG. 5 is an electric circuit diagram for controlling a solenoid valve in the hydraulic system diagram of FIG. 4. 1... Hopper body, 3... Stirring blade, 6... Hydraulic motor, 7... Solenoid valve, PSl, PS2... Pressure switch.

Claims (1)

[Scope of utility model registration request] A solid-liquid multiphase fluid hopper equipped with an agitation blade rotationally driven by a hydraulic motor includes a rotational torque detection device that detects the rotational torque of the agitation blade by the hydraulic motor, and a direction that is switched by a signal from the rotational torque detection device. A solid-liquid mixed phase is provided with a switching valve, and the forward and reverse rotation of the hydraulic motor is controlled according to the operation of the directional switching valve to release particles from being caught in the gap between the inner wall of the hopper body and the stirring blade. Fluid hopper.