JPS5916106B2 - Automatic adjustment device for concrete pump oil closing amount - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for automatically adjusting a closed loop enclosed in a drive cylinder such as a hydraulically driven concrete pump.

Conventionally, as a device for pumping concrete, there is a pump having a configuration in which two single reciprocating pontoons A and B each having a hydraulic drive section 1 and a concrete pumping section 2 are arranged in parallel, as shown in Fig. 1. provided.

This pump has the following hydraulic drive mechanism.

That is, the drive cylinders 1a, lbO of the hydraulic drive units 1, 1
A hydraulic conduit 3atab is connected to the lower side end.

The hydraulic conduits 3a and 3b, the pressurized hydraulic pressure feed pipe 4a, and the inlet pressurized oil discharge pipe 4b are connected to the main solenoid switching valve 5.
depending on 3a-4at3b 4b or 3a-4b
, 3b-4a are switched alternately so that they communicate.

This solenoid switching pulp 5 is switched by detection ends Ls, Ls that detect when the respective driving pistons 1c, 1d are located at the bottom dead center.

Further, the lateral upper ends of the drive cylinders 1at1b are connected by a communication pipe 6.

This communication pipe 6 includes a closed bend introduction pipe 6b having a needle valve 6a for introducing the closed bend, and a discharge pulp 6 for discharging the closed bend.
A closed lead-out pipe 6d having a diameter c is attached, and the introduction pipe 6b is connected to the closed replenishment system 1.

The portion formed by the valves 6a and 6c and the drive pistons 1c and 1d is hermetically sealed.

When driving the pump configured as described above, first, the solenoid pulp 5 is switched by the detection end L8 of the single pump A, and the pressurized oil pressure feed pipe 4a, the hydraulic pressure pipe 3a, the inlet pressurized oil discharge pipe 4b, and the hydraulic pressure pipe 3b are switched. are concatenated.

The drive piston 1c is pushed up by hydraulic pressure.

When the piston 1c is pushed up, the sealed closure passes through the communication tube 6 into the cylinder 1b and pushes down the piston 1d.

The depressed piston 1d pushes out the pressurized oil introduced into the lower part of the piston 1d.

This pressurized oil is discharged from the pipe 3bt4b.

In this way, the pistons 1c, 1d move from the positions indicated by the solid lines to the positions indicated by the two-dot chain lines.

Since the piston 1d is at the bottom dead center, the solenoid switching valve 5 is switched by the detection part Ls, and the pipe 4a and the pipe 3b are switched.
The pipe 4b and the pipe 3a are communicated with each other, and the piston 1d is pushed up and the piston 1c is pushed down.

Since the pistons 2at2b of the concrete pumping section 2 are attached to the same shafts as the drive pistons 1c and 1d of the drive section 1, they reciprocate as the drive pistons 1c and 1d reciprocate, and pump concrete.

At this time, it is necessary to maintain a one-stroke difference between the strokes of the single pump ASB so that when the piston 1c reaches the top dead center, the piston 1d comes to the bottom dead center.

The stroke difference between the single pumps A and B is determined by the amount of closed loop that is sealed.

By the way, in the above-mentioned pump, the amount of closing toward the piston tends to increase by the amount of leakage from the gap between the piston 1ctld and the driving cylinder 1at1b, since pressurized oil is pressurized from below the pistons 1c and 1d.

When the amount of closed oil increases, even if the piston 1c or 1d reaches the bottom dead center, the piston 1d or 1c does not reach the top dead center, and the pump performance decreases.

Therefore, it is necessary to adjust the amount of oil closed at regular intervals.

The amount of oil closed is normally adjusted by the following procedure.

First, the needle valve 6a is opened to introduce a closed bend from the closed bend replenishment system T, and the upper and lower pressurized oil of the pistons 1c and ld is released, and as shown in FIG. 2, both pistons 1cy1d are at the bottom dead center. position.

Close the needle valve 6a and open the discharge valve 6c.

Then, pressurized oil is introduced into either the cylinder 1a or 1b, and the piston is pushed up so that one of the pistons 1c or 1d comes to the top dead center.

Close the discharge valve 6c. With this operation, the piston I
Since c and Id are one stroke apart, the dual concrete pump is driven efficiently.

However, the above-mentioned adjustment of the amount of closed oil must be performed with the concrete pump stopped, and the procedure is troublesome.

Therefore, the oil closing amount can be set while the pump is running.
The advent of a device that is easy to operate has been awaited by civil engineering contractors.

The present invention has been made in consideration of the above-mentioned circumstances, and provides a device that appropriately adjusts the amount of oil closed in a hydraulically driven twin reciprocating concrete pressure pump that is being driven in a single motion. A detection means for detecting the position of each bottom dead center of the piston, and a closed bend is ejected when the detection results of these detection means are such that only the bottom dead center is detected and the top dead center is not detected. and a stop means for stopping closed discharge by the closed discharge means when the top dead center of the detection means is detected.

The present invention will be explained below with reference to the drawings.

・Figure 3 shows an implementation of a concrete pump equipped with a closing adjustment device according to the present invention, and the reference numerals 11 and 1 in the figure
1 is a drive unit of a hydraulically driven reciprocating unit pump A1B.

This drive unit 11.11 corresponds to the drive units 1, 1 in FIG.
Since it is driven by the same hydraulic mechanism as the hydraulic mechanism, the explanation thereof will be omitted, and the differences will be described below.

Hydraulic drive unit 11° 110 Magnets N1c and 11d are provided inside the drive pistons 11a and 11b.

Further, the drive cylinder 11e of the drive units 11,11.

Reed switch built-in tubes 11g and 11h are attached to the center of 11f over the entire length in the longitudinal direction of the cylinder.

Piston 11ay11b inside this tube 11gt11h
A reed switch LSa is built in at the bottom dead center position along with the changeover switches LS and LS of the solenoid changeover valve 5.

The reed switch LSa has a built-in switch tube 11g511
h may be provided on both sides or only on one side.

In addition, the reed switches LSb, L are located inside the switch built-in tubes 11g and 11b at the top dead center position of the piston 11a*11b.
Each has a built-in Sc.

These reed switches LS, Lsa, Lsb.

Lsc is actuated by the piston magnets 11e-11d.

Further, the communication pipe 6 is provided with a closed introduction pipe 12a provided with a pilot check valve 12.

This pilot check valve 12 is configured to close and discharge when a solenoid on-off valve SQL opens and pressure from the closing replenishment system 1 is applied.

Note that 5at6b are valves for manually introducing and discharging the closed bend, respectively.

In addition, the reed switches LS, Ls a, Lsb, and Lse were installed with built-in switch tubes 11g and 11b, and were placed inside the tubes. It may also be actuated by a magnet.

Figure 4 shows →l of the electrical circuit that controls the device shown in Figure 3.
This shows that.

In the figure, Ll and L2 are lines connected to positive and negative DC power supplies, respectively.

Ra is the coil of the first relay, and Ra is the coil of the first relay.
Ra2 t Ra3 is the first relay contact, Rb is
In the coil of the second relay, Rb1.

Rb2 is the contact of the second relay, Rc is the coil of the third relay, Rcl, Rc2, Rc3 s Ra4
is the contact point of the third relay.

Also, PB is a bush button switch, PLa, PLb
is a pilot lamp, and D is a diode.

Line L to which positive and negative power supply voltages are applied! 1. Between L2, a third relay normally closed contact Rc4, a first relay normally open contact Ra, and three pilot lamps RLa are connected in series from the line L1 to the line L2, and a bush button is connected in parallel with this. Switch PB.

The first relay coil Ra is connected in series, and the Ra3
The connection point between and PLa and the connection point between PB and Ra are connected.

Further, the normally open contact Rb1 of the second relay, the valve SQL, and the normally open contact Ra1 of the first relay are connected in series, and a pilot lamp PLb and a diode D are connected in parallel with SQL.

A reed switch Lsa is connected between the connection point of the line L1 and the above 5QL1Ral.

1st relay normally open contact Ra2, 3rd relay normally closed contact Rc
1. The second relay coils Rb are sequentially connected in series, and between the connection point of the line L1 and the Rel t Rb,
3rd relay normally closed contact Rc2, 2nd relay normally open contact Rb2
are connected in series.

Further, a reed switch Lsc and a third relay coil Re are connected in series between the line L1 and the connection point of the SQL and Ral, and a reed switch Ls is connected in parallel with Lsc.
b is connected to the third relay normally open contact Rc3.

Next, the operation of the apparatus shown in FIG. 3 and the electric circuit shown in FIG. 4 constructed in this way will be explained.

Now, drive the double reciprocating concrete pressure pump,
When the amount of closed bending gradually increases while pumping concrete, the piston 11as11b does not reach the top dead center, and the transporting capacity of the pump decreases.

By pressing the button switch PB, the amount of closing of the pump can be reduced and the pump can be returned to normal operation.

In other words, if the button switch PB is pressed while the pump is being driven, the normally open contacts Ral ~ 3 will self-hold,
At the same time, the pilot lamp PL lights up to indicate activation of this circuit.

At this time, the pistons 11a and 11b reach the bottom dead center even if the amount of closed bending is large.

When the piston reaches the bottom dead center, the reed switch Lsa is activated by the action of the magnet 11c or 11d inside the cylinder.
is ON, the second relay Rb is energized and the normally open contact R
b1 and b2 are also held on their own.

When the normally open contacts Ra1-3 and Rb1-2 are both held by themselves, the solenoid on-off valve SQL is opened, the pilot change valve 12 is operated, and the closed valve is discharged.

At the same time, the pilot lamp PLb lights up, indicating that the closed song is being discharged.

When the amount of closed bending gradually decreases, the piston 11a.

11b reaches the top dead center.

When the top dead center is reached, the reed switch Ls is activated by the action of the magnets 11c and 11d of the piston 11at11b.
b or Lsc is turned ON.

When Lsb or Lsc is turned on, the normally open contact Rc3 is maintained on its own.

As a result, the normally closed contact Rc1.2 is opened, so the self-retention of the normally open contact Rb1.2 is released, the solenoid open/close valve SQL is turned OFF, and the high lot change valve 12 is closed. Emission of music is stopped and the pilot lamp PLb is turned off.

At the same time, the self-retention of the normally open contacts Ra1 to Ra3 is released, the pilot lamp PLa is turned off, and the adjustment of the closing amount is completed.

Also, if the amount of closing is appropriate, the button switch P
Even if you press B, reed switch Lsb.

Since Lsc is turned ON by the action of the magnets 11c and 11d of the piston, the function of the adjustment circuit is completed, and virtually no discharge of the closed curve is performed.

As described above, the device according to the present invention automatically optimizes the closing amount by simply pressing the button switch while the concrete pump is still being driven. There is no need to stop the pumping of concrete and adjust the amount of closed bending through troublesome operations, and it is possible to pump concrete at all times in an optimal condition.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of a conventional hydraulic reciprocating concrete pump, Fig. 2 is an explanatory diagram of a method for adjusting the amount of closed bending of the same pump, and Fig. 3 is a diagram showing the structure of a concrete pump according to the present invention. FIG. 4 is a diagram showing →11 of the electric circuit for driving and controlling the pump shown in FIG. 3. A, B...Single pump, 2...Concrete pumping section, 2a, 2b...Concrete pumping piston, 3
a s3b...hydraulic conduit, 4a...pressurized hydraulic conduit,
4b...Introduction pressurized oil discharge pipe, 5...Main solenoid switching pulp, 6...Communication pipe, T...Closed replenishment system,
11...Hydraulic drive unit, 11 a t 11 b = drive piston, 11c. 11d...Magnet, 11e, 11f...Drive cylinder, 11g, 11h...Pipe with built-in reed switch, 12...Pilot chain valve, Ll...
Positive application line, L2...Negative application line, Lsa, Ls
b. Lsc...Lead female inch, PB...Push button inch, Ra...1st relay coil, Rai~3
First relay contact, Rb...Second relay coil, Rb
1-2...Second relay contact, Re...Third relay coil, Rel ~4m Third relay contact, PLa, ptb
-・Pilot lamp, D...diode.

Claims (1)

[Claims] 1.Equipped with two pressurized oil-driven reciprocating unit pumps in which the cylinder upper part of each pressurized oil drive unit is communicated with each other, and pressurized oil is supplied to the lower part of the drive piston of one of the drive cylinders of the unit pumps. to push up the piston,
This pushing up force causes the upper closed bend of each drive piston to be transferred to the other drive cylinder via the communication part, thereby pushing down the other drive piston,
By discharging the pressurized oil below the piston and repeating this operation alternately between these two unit pumps, in the concrete pump that drives the piston of the concrete pumping section, the upper part of the drive piston of each unit pump is Detection means for detecting the positions of dead center and bottom dead center, and when the detection results of these detection means are such that only bottom dead center is detected and top dead center is not detected, the closed bend is ejected. and a stop means for stopping closed discharge by the closed discharge means when the top dead center of the detection means is detected. Automatic oil amount adjustment device.