JPH0417820Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a concrete pump that transports ready-mixed concrete with a piston by alternately operating two concrete cylinders.

[Conventional technology]

As a concrete pump for piston-transporting fresh concrete, a pair of concrete cylinders are connected to a hopper for storing fresh concrete, and a swing valve is provided in the hopper to alternately connect the pair of concrete cylinders to a pipe for transporting fresh concrete. Structures with similar structures are known.

[Problems to be solved by the invention] In the concrete pump of the above type, when transporting hard fresh concrete with a small slump value, air is easily sucked into the concrete cylinder when the swing valve is switched and oscillated, and the intake air is compressed when the concrete cylinder is pumped, reducing the pumping force of the concrete cylinder, and when the swing valve swings to switch communication between the concrete cylinder and the transport pipe, it expands and causes fresh concrete to flow back toward the hopper. As well as reducing the transport efficiency of concrete pumps,
There is a problem in that the intake air momentarily expands at the discharge end of the transport pipe, scattering the ready-mixed concrete, not only polluting the surrounding area but also being dangerous.

SUMMARY OF THE INVENTION An object of the present invention is to provide a concrete pump that can eliminate intake air within a concrete cylinder and prevent problems caused by the intake air.

[Means for solving problems]

In order to achieve the above object, the present invention includes a pair of concrete cylinders connected to a hopper containing fresh concrete, and in the hopper, the pair of concrete cylinders are alternately connected to a pipe for transporting the ready-mixed concrete. In a concrete pump provided with a swing valve for communication, the upper end face of the swinging end of the swing valve and the upper end face of the opening of each concrete cylinder are aligned with each other in a state where the swing valve is completely communicated with the concrete cylinder. The structure is such that an air vent groove that forms an air vent hole with a diameter of 3 to 6 mm is provided upward.

[Effect]

The swing valve swings left and right to alternately connect the pair of concrete cylinders to the transport pipe, and the above pair of concrete cylinders alternately suck the fresh concrete in the hopper, and when the swing valve is connected, The sucked fresh concrete is pushed out towards the transport pipe.

In the above operation, when air is sucked into the concrete cylinder together with the fresh concrete, the intake air is provided at the end face of the swinging end of the swing valve when the concrete cylinder pumps the fresh concrete into the transport pipe. The air is discharged to the outside through an air vent hole formed by matching the air vent groove provided in the concrete cylinder with the air vent groove provided on the open end surface of the concrete cylinder. Therefore, the suction air is not compressed to reduce the pumping force of the concrete cylinder, or the fresh concrete does not flow back into the hopper, which reduces the pump's transport efficiency. It does not cause any danger by ejecting forcefully to the surrounding area.

The diameter of the air vent hole is 3 to 6 mm, so
Intake air can be efficiently discharged without adversely affecting the transportation of fresh concrete. Furthermore, since the air vent hole is formed by matching two air vent grooves, it is less likely to be clogged with sand or the like.

〔Example〕

1 to 3 show an embodiment of the present invention, in which numeral 1 indicates a hopper for storing fresh concrete. On one side of the hopper 1, there is a pair of concrete cylinders 2 equipped with pistons 2a, which are actuated by a drive cylinder (not shown).
2 are connected in parallel to each other, and one transport pipe 3 is provided on the other side. Further, in the hopper 1, a swing valve 4 has one end 4a connected to a transport pipe 3.
It is rotatably fitted into the base 5 on the side, and the other end (swinging end) 4b is disposed on the concrete cylinder 2 side and pivotally supported by a rotating shaft 6, so that it can freely swing.

The arm member 7 attached to the rotation shaft 6 has a piston rod 8a of the swinging drive cylinder 8.
are connected and rotated about the rotation shaft 6 by the expansion and contraction operation of the swinging drive cylinder 8, swinging the swing valve 4 left and right, thereby making the pair of concrete cylinders 2 alternately communicate with the transport pipe 3. It is said to be composed of

Air vent grooves 4c and 2c are formed in the upper end surface of the swinging end 4b of the swing valve 4 and the sliding portion A of the concrete cylinder 2, that is, in the upper end surface of the opening. These air vent grooves 2
c and 4c are for literally extracting the air that has entered the swing valve 4 during swinging to the outside.When the concrete cylinder 2 and the swing valve 4 are in complete communication, the air vent holes 2c and 4c align with each other and the air is vented. A hole K is formed therein. If the diameter of the air vent hole K is smaller than 3 mm, the intake air cannot be efficiently discharged, and if the diameter is larger than 6 mm, the transport of fresh concrete will be adversely affected, so the diameter is set to 3 to 6 mm.

There are various shapes of the air vent grooves 2c and 4c, such as straight ones as shown in Fig. 4, and outward opening ones as shown in Fig. 5.The shape is arbitrary, but as shown in Fig. 5, Forming the concrete makes it difficult for the sand in the fresh concrete to get clogged, which is good.

9 is a stirring blade for stirring the fresh concrete in the hopper 1, and 10 is a mesh plate provided at the upper opening of the hopper 1.

Next, the operation of the concrete pump according to the present invention configured as described above will be explained.

As is well known, the piston 2a of the concrete cylinder 2 and the swing valve 4 operate in conjunction with each other, and when the swing valve 4 communicates with one of the concrete cylinders 2, the piston 2a of that concrete cylinder 2 advances and The fresh concrete in the cylinder 2 is fed under pressure to the swing valve 4. At this time, the piston 2a of the other concrete cylinder 2 moves back and sucks the fresh concrete in the hopper 1. When the piston 2a of the one concrete cylinder 2 finishes moving forward,
The swing valve 4 swings and communicates with the other concrete cylinder 2, and receives the pumping of fresh concrete by the piston 2a of the concrete pump cylinder 2. At this time, the piston 2a, which has moved forward as described above and finished pumping the ready-mixed concrete, moves back and sucks in the ready-mixed concrete.

The above operation is repeated to transport the ready-mixed concrete in the hopper 1 by the piston. However, when the ready-mixed concrete in the hopper 1 is sucked into the concrete cylinder 2, if air is inhaled together with the ready-mixed concrete, the intake air is transferred to the piston. When the pressure increases when the air vent 2a moves forward, the air is discharged from the air vent hole K formed by the alignment of the air vent grooves 2c and 4c. Therefore, the intake air moves to the transport pipe 3 in a compressed state, and when the swing valve 4 swings, it causes the fresh concrete to flow backwards, or it blows out forcefully from the discharge end of the transport pipe 3, scattering the ready-mixed concrete around. There's nothing to do.

Note that the air vent hole can also be provided in the sliding portion B between the one end 4a of the swing valve 4 and the cap 5 in the same manner as described above. The air vent groove does not need to be provided vertically upward, and may be provided obliquely upward.

[Effect of idea]

As explained above, the concrete pump according to the present invention has a pair of concrete cylinders connected to a hopper that accommodates fresh concrete, and
In the concrete pump, a swing valve is provided in the hopper to alternately connect the pair of concrete cylinders to the ready-mixed concrete transport pipe. At the top of the end face, the swing valves are aligned with each other and are in full communication with the concrete cylinder.
Since the air vent groove forming the air vent hole with a diameter of 6 mm is provided upward, the air sucked into the concrete cylinder can be discharged to the outside. For this reason, the fresh concrete pumping force of the concrete cylinder is not reduced due to the compression of the intake air, and the fresh concrete does not flow backwards, and the compressed air does not cause fresh concrete to blow out from the discharge end of the transport pipe and pollute the surrounding area. , does not pose any danger. Furthermore, since the air vent hole is formed by matching two air vent grooves, it is less likely to be clogged with sand, etc., and has the advantage that air is always properly discharged.

[Brief explanation of drawings]

Fig. 1 is a perspective external view of the concrete pump according to the present invention, Fig. 2 is a sectional view, Fig. 3 is a detailed sectional view of the sliding part of the concrete cylinder and swing valve, Fig. 4 is a sectional view of the air vent groove, FIG. 5 is a sectional view of another example of the air vent groove. 1...Hotsupa, 2...Concrete cylinder,
2c...air vent groove, 3...transport pipe, 4...swing valve, 4c...air vent groove, K...air vent hole.

Claims (1)

[Scope of utility model registration request] A pair of concrete cylinders 2, 2 are connected to a hopper 1 that accommodates fresh concrete, and a swing valve is provided in the hopper 1 to alternately communicate the pair of concrete cylinders 2, 2 to a transport pipe 3 for fresh concrete. 4, a swing valve 4 is provided at the upper end surface of the swinging end 4b of the swing valve 4 and at the upper end surface of the opening of each concrete cylinder 2, 2.
When the cylinders are fully connected to the concrete cylinder 2, air vent holes with a diameter of 3 to 6 mm are formed in alignment with each other.
(k) A concrete pump characterized in that air vent grooves 4c and 2c forming the air vent grooves 4c and 2c are provided facing upward.