JP2535698Y2 - Automatic block prevention device for concrete pump - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic blockage prevention device for a concrete pump for pumping fluid ready-mixed concrete from a location remote from a site where the ready-mixed concrete is poured, such as a construction site or a construction site. It is.

[0002]

BACKGROUND OF THE INVENTION One of the biggest problems in the practice of pumping is that the ready-mixed concrete becomes stuck in the pipe {clogging}, and in extreme cases, one of the piston
The pump may be closed every stroke, so the operator manually turns the pump operation switch on and off in small increments.
The blockage accident is prevented by repeating the process (see Japanese Utility Model Publication No. 62-12875).

[0003]

As described above, it is very burdensome for an operator to prevent a concrete pump from being blocked, and there has been a demand for improvement in this respect. The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent a concrete pump from being blocked without putting a burden on an operator.

[0004]

Means for Solving the Problems In order to achieve the object, the present invention provides a housing for putting ready-mixed concrete.
And the suction and discharge of ready-mixed concrete in the hopper.
A pair of cylinders and a pair of cylinders
The connection with the transport pipe is linked to the suction and discharge operation of the cylinder.
The free end should alternately communicate with each cylinder with the connecting end as a fulcrum.
Swinging pipe and a pair of cylinders
For cylinder operation that switches to perform discharge operation alternately
Electromagnetic directional valve and swing for swinging the swing pipe
Directional control valve for operating the pipe
Solenoid directional control valve for cylinder operation
The first changeover switch to the cylinder control circuit
Through a connection circuit that is always conductive and a disconnection having a timer contact.
And a first switching switch.
The second changeover switch that works with the switch
The timer to activate and deactivate repeatedly.
To the disconnection circuit side of the first changeover switch.
Operation via the second changeover switch by the changeover operation of
The timer started pumping and stopping the concrete pump.
The stop is repeated .

[0005]

[ Function ] With this configuration , during operation,
If the blockage of Nkurito occurs, Misao the switch
And work to activate the timer, the power supply to the switching valve control circuit
Concrete is pumped by repeatedly cutting and contacting
The piston was moved in small increments , resulting in a pipe
Effectively eliminates blockage of ready-mixed concrete.

[0006]

FIG. 1, FIG. 2 and FIG. 3 show one embodiment of the present invention. In the drawings, reference numeral 1 denotes a concrete pump, which is a side wall of a hopper 2 into which ready-mixed concrete is put. And the openings 3a, 4 at one end.
a is disposed in the hopper 2 and a pair of cylinders 3 and 4 respectively communicated with the hopper 2, one end 5a is rotatably supported by the other side wall of the hopper 2, and the other end 5b is A crank-shaped swing pipe 5 alternately communicated with one of the cylinders 3 and 4;
Pistons 6 and 7 respectively slidably disposed within 4
And a hydraulic device 8 connected to the other ends of the cylinders 3 and 4 and driving the pistons 6 and 7 through rods 6a and 7a.
A swing shaft 9 connected to one end 5a of the swing pipe 5 and having one end protruding outside the hopper 2; and a hydraulic device connected to a protruding end of the swing shaft 9 by a crank mechanism 10. It consists of eleven. In addition, each cylinder 3,
4 are connected to each other at the other end.

The hydraulic device 8 comprises actuators 12 and 13 connected to pistons 6 and 7 via rods 6a and 7a, respectively, and a pipe connected to one end of each of the actuators 12 and 13.
An electromagnetic directional control valve 16 connected by 14 and 15 and a hydraulic pump connected to the electromagnetic directional control valve 16 by a pipe 17
And a motor 19 for driving the hydraulic pump.

The actuators 12, 13 are connected to each other at the other end by a pipe 20, and a space A formed by the pipe 20 and the actuators 12, 13 is supplied by pipes 14, 15. The oil is sealed off from the oil to be made. Further, magnets 21 and 22 are provided at ends of the rods 6a and 7a of the pistons 6 and 7 on the actuator side, respectively, and reed switches 23 and 24 operated by the magnets 21 and 22 are respectively provided with pistons 6 and 7 respectively. It is installed at the turnback position.

The above-described electromagnetic directional control valve 16 is a 4-port, 3-position
Each piston configured as a switching valve and retracting alternately
Each of the above reed switches for detecting and outputting backward movement of 6, 7
The solenoids 25 and 26 are activated by output signals from 23 and 24.
Switch the direction of oil flow and alternately move pistons 6 and 7
In addition to reciprocating, a first changeover switch 56 described later
is operated, the contact 57a of the timer relay
It changes to the neutral position intermittently by repeating N and OFF.
To stop oil supply to cylinders 12 and 13.
I do.

The hydraulic device 11 includes an actuator 27 connected to the crank mechanism 10 and an electromagnetic directional control valve 30 connected to pipes 28 and 29 at both ends of the actuator 27.
A hydraulic pump 32 connected to the electromagnetic directional control valve 30 by a pipe 31, and a motor 33 for driving the hydraulic pump 32
It is composed of In addition, two solenoids 34 for switching the direction of oil flow are provided on the electromagnetic directional control valve 30.
35 is provided, and the two solenoids 34 and 35 are alternately excited to control the swinging motion of the swing pipe 5.

Next, an electric circuit for driving the concrete pump 1 will be described with reference to FIG. In the figure, reference numeral 44 denotes a power switch, one end of which is connected to the power supply + side, and the other end of which is connected to the anodes of the thyristors SCR ₁ and SCR ₂ , respectively. The cathode of the thyristor SCR ₁ is connected to the anode of the diode D _1. The cathode of the diode D _1, along with being connected to one end of the solenoid 25 via the b-contact 45a of the relay 45 is connected to one end of the solenoid 26 through a contact 45b of the relay 45.

[0012] The cathode and the power of the diode D ₁ - resistor R ₁ between the side are connected. The cathode of the diode D ₂ is connected to one end of the solenoid 25 through a contact 45c of the relay 45, and relay 45
Is connected to one end of the solenoid 26 via a contact b 45d. Moreover, the cathode and the power of the diode D ₂ - resistor R ₂ is connected between the side.

[0013] The gate of the thyristor SCR ₁ is resistance R
₃ is connected to one end, the other end of the resistor R ₃ is relay 47
Are connected to one end of the a contact 47a and one end of the b contact 47b. The gate of the thyristor SCR ₂ is connected to one end of the resistor R _4, the other end of the resistor R ₄ is connected to one end of the one end and the contact b 47d of the relay 47c. Then, one end of the resistor R ₃ and the thyristor SCR ₁
Between the cathode of the resistor R ₅ and a capacitor C ₁ are connected in parallel, and the resistor R ₄ one end and a thyristor SC
Between the cathode of R ₂ and a resistor R ₆ and a capacitor C ₂
And thyristor SCR ₁ are connected in parallel.
Capacitor C _3, C ₄ are connected in series between the cathode of the cathode and the thyristor SCR _2.

Further, the other end of the b contact 47b of the relay 47 and a
The other end of the contact 47c is connected to one end of the reed switch 23, and the other end of the a contact 47a and the other end of the b contact 47d of the relay 47 are connected to one end of the reed switch 24.
The other end of the reed switch 23 and the other end of the reed switch 24 are connected to the other end of the power switch 44 via the a contact 48a of the relay 48, and the other end of the b contact 47b of the relay 47 and the power switch. The b contact 49a of the relay 49 and the b contact 48b of the relay 48 are connected in series with the other end of the switch 44.

One end of the relay 46 and one end of the relay 49 are connected to the other end of the power switch 44, and the other end of the relay 46 and the other end of the relay 49 are connected to the power supply side via the pump switch 50. It is connected to the. An a contact 48c of the relay 48 and a b contact 49b of the relay 49 are connected in parallel between the other end of the power switch 44 and one end of the relay 48, and the other end of the relay 48 is connected to the power supply side. It is connected to the. Further, between one end of the relay 45 and the other end of the power switch 44, an a contact 47e of the relay 47 and a maximum pressure test switch
The a contact 51a of 51 is connected in parallel, the other end of the relay 47 is connected to the power supply side through the a contact 52a of the piston reverse switch 52, and the auto reverse circuit 53 is connected through the diode D. Connected to one end.

The auto-reverse circuit 53 is configured such that when the concrete pump 1 is closed and the hydraulic pressure of the hydraulic device reaches the maximum pressure, a pressure switch 54 in the circuit is activated, and the two ends of the circuit conduct for a certain period of time. Have been. And, between the other end of the auto reverse circuit 53 and the power supply (−) side, an auto reverse switch 55, a b contact 51b of the highest pressure test switch 51, and the piston reverse switch 52
And the b contact 52b are connected in series. The a-contact 51a and the b-contact 51b of the highest pressure test switch 51 are linked to each other.
The contact 52a and the b contact 52b are linked.

On the other hand, the other ends of the solenoids 25 and 26 are
Manually operated via the a contacts 46a and 46b of the relay 46
They are connected respectively to the first change-over switch 56a to be.
The "OFF" side of the changeover switch 56a constitutes a connection circuit which is always connected to the power supply side, and the "ON" side of the changeover switch 56a is connected to the power supply through a timer relay contact 57a.
And an intermittent circuit connected to the
The switch 56a is interlocked with the second changeover switch 56b,
When switched to the “ON” side, the power supply was connected to the + side.
Connect the other end of the twin timer 57 to the power supply side.
It has been formed.

Next, the operation of the automatic blockage preventing device for a concrete pump configured as described above will be described.
If the movement of the concrete pump piston continuous operation, the power switch 44 is ON, the then pump switch 50 to ON, the first changeover switch 56a "OFF" side
Connected to the second switch 56b
Is also switched to the "OFF" side, and on the other hand, the relay 48 is energized, the a contacts 48a, 48c are closed and the b contact 48b is opened, the relays 46 and 49 are energized, and the a contacts 46a, 46b are closed. <br/> b contact 49a with Jill, 49b to be had opened, reciprocating the pistons 6 and 7 of the concrete pump 1.

[0019] Then, when one of the piston 6 is retracted to a predetermined position, closing the reed switch 23, the gate current to the gate of the thyristor SCR ₁ from the lead switch 23 via the b-contact 47b and the resistor R ₃ of the relay 47 flow, the thyristor SCR ₁ is turned on. As a result, the exciting current is supplied from the thyristor SCR ₁ through the diode D ₁ to the solenoid 25 via the contact 45 a of the relay 45, and to the solenoid 35, respectively.
Works.

As a result, the piston 6 starts to move forward, and the piston 7 starts to move backward, and moves constantly until it reaches the stroke end. At the same time, since the swing pipe 5 communicates with the opening 3a of the cylinder 3, the piston 6 feeds the ready-mixed concrete in the cylinder 3 to the transport pipe P via the swing pipe 5 and the piston 7 moves from the hopper 2 to the cylinder 4 in the cylinder 4. Inhale ready-mixed concrete.

[0021] When the piston 7 is retracted to a predetermined position, closing the reed switch 24, a gate current flows through the gate of the thyristor SCR ₂ from the reed switch 24 via the b-contact 47d and the resistor R ₄ of the relay 47, thyristor SCR ₂ is turned on. As a result, the excitation current from the thyristor SCR ₂ through the diode D ₂ becomes
The solenoids 26 and 34 are operated by being supplied to the solenoid 26 and the solenoid 34 via the b contact 45d of the relay 45, respectively.

As a result, the piston 6 starts retreating, and the piston 7 starts moving forward, and moves constantly until it reaches the stroke end. At the same time, since the swing pipe 5 communicates with the opening 4a of the cylinder 4, the piston 7 feeds the ready-mixed concrete in the cylinder 4 to the transport pipe P via the swing pipe 5, and the piston 6 moves from the hopper 2 into the cylinder 3. Inhale ready-mixed concrete. in this way,
The ready-mixed concrete is sucked into the cylinders 3 and 4 from the hopper 2 and is sent to the predetermined place by the transport pipe P through the swing pipe 5.

On the other hand, when the concrete pump is closed by the ready-mixed concrete during operation, the first changeover switch 56a is switched to the "ON" side and the second changeover switch 56a is operated in conjunction therewith.
Switch 56b is set to the "ON" side . As a result, the twin timer 57 starts operating, turns on and off the contact 57a of the timer relay at a preset time interval, and repeatedly cuts off and makes contact with the electromagnetic direction switching valve 16. Therefore, as shown in FIG. 3, the exciting current is supplied to the solenoids 25 and 26 in a pulsed manner (in this embodiment, ON time t1 = 1 second, OFF time t2 = 0.5 second), and the ready-mixed concrete is pumped. Pistons 6 and 7 move in small increments
Then, while the pumping operation is continued, the arching of the ready-mixed concrete generated in the pipeline by the pulsation is broken to eliminate the blockage.

[0024]

[Effects of the Invention] As described above, according to the present invention,
From the first changeover switch, the electromagnetic direction for cylinder operation
Always-on connection to the cylinder control circuit that switches the switching valve
Circuit and disconnection circuit with timer contact
And a second switch interlocked with the first switch
A timer that repeatedly connects and disconnects timer contacts with a switch
Can be switched between an active state and an inactive state,
Of the changeover switch to the disconnection circuit side
The concrete pump by the timer
Since the stop operation is repeated , not only can the concrete pump blockage accident be prevented without any trouble for the operator, but also the piston can be small.
By moving it, the blockage of the ready-mixed concrete in the pipeline can be effectively eliminated while continuing the work of pumping the ready-mixed concrete.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of the present invention.

FIG. 2 is a circuit diagram showing an embodiment of the present invention.

FIG. 3 is a time chart of an exciting current flowing through a solenoid showing one embodiment of the present invention.

[Explanation of symbols]

 1 Concrete pump 8 Cylinder drive hydraulic system 16 Electromagnetic directional switching valve 25,26 Solenoid 56a, 56b selector switch 57 Twin timer 57a Timer relay contact

Claims (1)

(57) [Scope of request for utility model registration] 1. A hopper for charging ready-mixed concrete, a pair of cylinders for sucking and discharging the ready-mixed concrete in the hopper, and one cylinder provided in the hopper,
In conjunction with the suction and discharge operation of the pair of cylinders, the transport tube
A swing pipe which swings to pass with the alternately to each cylinder of the free ends of the connecting end as a fulcrum of the switching Cie order to alternately performed a suction and discharge operation on the pair of cylinders
Electromagnetic directional control valve for operating the cylinder and the swing pipe
Directional control valve for swing pipe operation that swings
And a cylinder for switching the solenoid-operated directional control valve for operating the cylinder.
Through the first changeover switch to the control circuit
Between the connection circuit and the intermittent circuit with timer contacts
Connectable with the first changeover switch
The above-mentioned timer contact is repeated by the second changeover switch
The timer to be connected and disconnected can be switched between active and inactive
To the disconnection circuit side of the first changeover switch
Is switched through the second changeover switch.
Activated timer sends pressure to concrete pump
An automatic blockage prevention device for a concrete pump, characterized in that the operation and the stop are repeated .