JPH0553945B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for cleaning the inside of a discharge side pipe of a concrete pump.

Concrete pumps having the structure shown in FIGS. 1 and 2 are generally well known.

The concrete pump shown in FIG.
A slide valve-type switching valve 4 is provided at the forked part so that the concrete enters the casing 2 and is divided into two parts, and the flow direction of the concrete is switched to left and right by alternately opening and closing the switching valve 4. be.
Further, two concrete cylinders 5 arranged on the left and right are connected to each opening of the casing 2, and each concrete cylinder 5 has a cleaning chamber 6.
The hydraulic cylinders 7, which are the main cylinders, are connected through the pistons 8 and 8 in the hydraulic cylinders 7, respectively.
A piston 9 in the concrete cylinder 5 is connected with a rod 10, while a discharge pipe 11, which is a straight pipe or a curved pipe removably connected with a pipe joint 12, is connected to the discharge port of the casing 2. By moving the left and right hydraulic cylinders 7 forward and backward alternately in accordance with the switching operation of the switching valve 4, when concrete is sucked into one concrete cylinder, the concrete that has been sucked into the other concrete cylinder is pushed out. The operations are performed alternately so that concrete is discharged into the discharge pipe 11.

In addition, the concrete pump shown in FIG. 2 has a switching pipe 13 built in the concrete hopper 1 that can move horizontally or pendulum-like in the left-right direction, instead of the sliding valve type switching valve 4. has an opening at one end that connects with the concrete cylinders provided on the left and right, and an opening that communicates with the discharge pipe 11 at the other end, and among the two concrete cylinders,
When one concrete cylinder communicates with one suction part of the hopper 1, the other concrete cylinder communicates with the discharge pipe 11 via the switching pipe 13.
It is designed so that concrete is alternately sucked and discharged. 14 is a concrete stirring device.

In any type of concrete pump, not limited to the above example, after the pumping of concrete at the site is completed, pipe cleaning is essential to prevent concrete from hardening and adhering within the pipes.

As shown in FIG. 3, the conventional pipe cleaning method uses the cleaning chamber 6 as a water pump in order to supply water from the water tank 15 to the cleaning chamber 6 and guide it from the cleaning chamber 6 to the discharge piping 11. , and discharge piping 11
Remove the joint 12 between the straight pipe part and the bent pipe part and clean the cleaning chamber 6.
A water supply pipe 16 is directly connected to the discharge pipe 11 as shown in the figure, and a cleaning filler 17 such as a sponge packed in the curved pipe portion 11a is transferred into the pipe 11 by force-fed water for cleaning. There is.

However, in the conventional cleaning device described above, the cleaning chamber 6 is used as a water pump, and the water outlet of the cleaning chamber 6 is connected to the discharge pipe 11 by a water supply pipe 16 such as a hose, so such piping is not necessary. In addition, there is a problem that concrete cannot be removed over a wide range L between the concrete cylinder 5 and the location where the discharge pipe 11 is removed.

The main purpose of the present invention is to make it possible to clean areas that cannot be cleaned using the conventional method, and also to eliminate the need for piping and the need to remove the discharge pipe as in the conventional method. The concrete piston, which incorporates a check valve that is operated by the pressure difference between the rod side and the head side as it moves, can be moved back into the cleaning chamber, and the cleaning filling is inserted into the concrete cylinder from the cleaning chamber. When the concrete piston is returned to its original stroke and operated, the water in the water tank is sucked into the cleaning chamber, and the water in the cleaning chamber is drained at high pressure into the concrete cylinder, the filling is transferred, and the concrete piston is The concrete inside the cylinder can be removed and there is no need to remove the discharge piping.

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 4 and 5 show the main parts of the present invention, and the other configurations are the same as those shown in FIGS. 1 and 2.

In the cleaning device of the present invention, a sealable lid 6b is provided on the upper surface of a casing 6a constituting a cleaning chamber 6 to form a pressure vessel, and only a water supply pipe 18 from a water tank 15 is connected to the cleaning chamber 6. A check valve 19 is provided in the middle of the water supply pipe 18 to prevent backflow. Further, the concrete cylinder 5 side of the cleaning chamber 6 is opened with the same diameter as the inner diameter of the concrete cylinder 5 so that the concrete piston 20 can retreat from the inside of the concrete cylinder 5 to the inside of the cleaning chamber 6, and the concrete piston 2
0 has a check valve 21 that opens when the pressure on the cleaning chamber 6 side becomes greater than the pressure on the discharge side.

For details of the concrete piston 20, see Section 6.
As shown in the figure, a connecting metal fitting 23 having an opening 24 in the center and a recess 25 in the front side is integrally attached to the rear surface of the valve plate 22 with bolts 26, etc. The rod 10 with the passage 27 opened, which communicates with the opening 24, is fixed with a bolt 28 or the like, and the water pressure on the rod side is applied to the passage 27.
7. It is possible to act on the back surface of the valve plate 25 through the opening 24 and the recess 25. On the other hand, a guide rod 29 is slidably inserted through the center of the valve plate 22.
A disk 32 having a ring-shaped groove 31 on the rear surface that communicates with an ejection hole 30 provided in the valve plate 22 is fitted to the front end of the guide rod 29, and a nut 33 is screwed thereto. and valve plate 22
A spring 34 is interposed between the disc 32 and the valve plate 22 under the force of the spring 34 to close the spout hole 30. When overcoming the elasticity of the piston 20, a gap is created between the disc 32 and the valve plate 22 to constitute a check valve 21 which jets high-pressure water from the rod side of the piston 20 to the head side.

Now, when concrete has been pumped and it is time to move on to cleaning work, the concrete piston 20 located inside the concrete cylinder 5 is moved back into the cleaning chamber 6, the lid 6b of the cleaning chamber 6 is removed, and the worker A cleaning filler 17 such as a sponge for separating water and concrete is packed into the concrete cylinder 5 from the cleaning chamber 6. Cleaning chamber 6 of the piston 20
For inward retraction, a limit switch (not shown) is provided in two stages, and normally when the piston 20 is returned to the rear end of the concrete cylinder 5 and the limit switch is activated, the piston reverses and moves forward. When pulling out the piston, switch the circuit and operate the hydraulic cylinder 7 to move the piston further backward, and stop it when the piston moves backward by the stroke S shown in Fig. It may be removed when retracting 20.

After filling the filler 17 as described above, the piston 20 is inserted into the concrete cylinder 5, and the piston 20 is advanced to advance within the concrete cylinder 5. At this time, water is supplied into the washing chamber 6 from the water tank 15. Next piston 20
to retreat. By returning the piston 20,
The pressure on the rod side of the piston 20 is prevented from flowing back by the check valve 19 for preventing backflow.
When the rod rises and the check valve 21 opens, the high pressure water on the rod side flows into the spout hole 3 that constitutes the check valve 21.
It erupts from 0. Sponge-like cleaning stuffing 17
isolates the water from the concrete, so that the ejected water is collected between the piston 20 and the filling 17.

Next, the piston 20 is moved forward. As a result, the water between the filling 17 and the piston 20 is pressurized and transferred to the discharge piping side, and at the same time, the filling 17 is sent to clean the inside of the piping.

In the above example, the opening 24 and the check valve 21 are located at the center of the valve plate 22, but of course they do not need to be located at the center. In addition, the connecting hardware 23 and the opening 2
4. The concave portion 25 and the passage 27 may be omitted and the jet hole 30 of the valve plate 22 may be configured to communicate directly with the cleaning chamber 6.

In the present invention, since the filler 17 is filled into the concrete cylinder 5 from the cleaning chamber 6, the range L, which could not be cleaned conventionally, can be cleaned, and there is no need to remove the discharge pipe 11 accordingly.

As described above, according to the cleaning device of the present invention,
Since the pipes are cleaned from inside the concrete cylinder, there is no concrete left inside the cylinder, and a wide area can be reliably cleaned, from the water outlet in the cleaning room to the discharge piping. There is no need to connect with a hose, etc., and there is no need to remove piping, and since the check valve is permanently installed on the concrete piston, there is no need to incorporate the check valve into the concrete pump every time concrete is cleaned. Excellent effects such as easy switching between concrete pumping work and cleaning work can be achieved.

[Brief explanation of the drawing]

Fig. 1 and Fig. 2 are both configuration examples of a concrete pump, Fig. 3 is a schematic diagram of a conventional cleaning device, Fig. 4 is a sectional view showing the main parts of the cleaning device of the present invention, and Fig. 5 6 is a sectional view showing the state during cleaning, and FIG. 6 is an enlarged view of the concrete piston in the apparatus of the present invention. 1 is a concrete hopper, 5 is a concrete cylinder, 6 is a cleaning chamber, 7 is a hydraulic cylinder, 11
15 is a discharge pipe, 15 is a water tank, 17 is a cleaning filler, 20 is a concrete piston, 21 is a check valve, 22 is a valve plate, 23 is a connecting hardware, 25 is a recess, 30 is an ejection hole, and 32 is a disc. .

Claims (1)

[Claims] 1. In a concrete piston of a concrete pump, which pumps concrete by repeatedly suctioning and discharging it through a concrete cylinder that alternately reciprocates concrete in a concrete hopper, the pressure on the rod side increases to the head side due to the movement of the concrete piston toward the rod side. A check valve is installed which opens when the pressure exceeds the pressure to allow communication between the rod side and the head side, and the concrete piston is retracted to a washing chamber at the rear of the concrete cylinder, and the washing chamber is filled with water. A cleaning device for a concrete pump, characterized in that a water supply pipe from a tank is connected via a check valve for preventing backflow.