JPH0357306B2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention continuously pumps ready-mixed concrete by causing a cylinder device consisting of a concrete cylinder and a hydraulic cylinder to alternately suck in and discharge the ready-mixed concrete. This invention relates to the structure of a switching section between suction and discharge of fresh concrete in a pump for pumping fresh concrete.

BACKGROUND OF THE INVENTION Ready-mixed concrete is essential for carrying out construction work, and as construction sites and construction methods become more diverse, improving the efficiency of its supply has become an increasingly important issue in recent years. Concrete pumps are generally used to supply ready-mixed concrete, but they have become larger year by year, and devices with a supply capacity of 100 m ³ or more per hour are now available.

However, such large concrete pumps are expensive, and because of their large size, they are difficult to move due to their weight, shape, etc., and may not be suitable for some construction sites. Moreover, in general, the amount of fresh concrete required at one time in civil engineering work and construction work is mostly 20 to 50 m ³ , so this capacity is often not needed. Therefore, small-sized concrete pumps that are highly mobile, can be adapted to any site, and are inexpensive are being reconsidered, and the provision of efficient pumps is expected.

On the other hand, concrete pumps can be roughly divided into squeeze type and piston type, and each type is used to take advantage of its characteristics. The squeeze method is suitable for construction work where the aggregate in fresh concrete is 25 mm or less, but it cannot be used for civil engineering work where the aggregate is as large as approximately 40 mm and low slump occurs. Therefore, in order to use it for a variety of purposes including civil engineering work, the piston method must be used.

Problems to be Solved by the Invention The piston system continuously pumps fresh concrete by having a cylinder device consisting of a concrete cylinder and a hydraulic cylinder alternately suck and discharge the fresh concrete. Therefore, the structure of the suction and discharge switching section is a problem, and various systems are available. First, the entire cylinder device is slid laterally, and the concrete cylinder of the cylinder device is connected to the suction and discharge ports. A structure in which the outlet is connected alternately is also provided (Special Publication No. 51-35243). However, the most efficient method is not to slide the entire cylinder device, but to place a three-way on-off valve at the bottom of the hopper, and the hopper is opened and closed by the opening and closing action of the three-way on-off valve. The concrete cylinder communicates with the concrete cylinder to suck in fresh concrete (at this time, the concrete cylinder and discharge port are shielded by a three-way on-off valve),
When the suction is finished, the three-way on-off valve is closed, and the concrete cylinder and discharge pipe are communicated with each other for discharge (at this time, the concrete cylinder and hopper are shielded from each other by the three-way on-off valve). but,
Conventionally, the above-mentioned method in which a three-way on-off valve is installed at the bottom of the hopper is mechanically simple and superior, but when the three-way on-off valve is opened and closed to switch between suction and discharge of fresh concrete, the amount of water contained in the ready-mixed concrete is removed. Aggregate gets caught in the three-way on-off valve, making it impossible to open and close completely, preventing smooth pumping, and only the paste in the fresh concrete leaks out through the gap where the aggregate is caught. Therefore, the fresh concrete in the concrete cylinder becomes dehydrated, and the concrete cylinder becomes clogged.
Therefore, the biggest problem is that the aggregate in the fresh concrete gets caught in the mix, and it is impossible to use a pump for pumping fresh concrete that has a three-way valve installed at the bottom of the hopper to switch between sucking and discharging the fresh concrete. It was considered a thing.

Therefore, the present invention has been developed to prevent the aggregate contained in the ready-mixed concrete from being caught even when the three-way on-off valve installed at the bottom of the hopper is used to switch between suction and discharge of the ready-mixed concrete. The object of the present invention is to provide a pump for pumping fresh concrete that can continuously and smoothly pump fresh concrete without clogging the fresh concrete due to jamming of materials.

Means for Solving the Problems In order to achieve the above object, the present invention provides a three-way opening/closing valve at the bottom outlet of a hopper into which ready-mixed concrete is charged, and a valve box disposed at the lower part of the hopper and the hopper. and a cylinder device for pressurizing the fresh concrete is connected to the valve box so that the cylinder device alternately sucks in and discharges the fresh concrete, and the three-way opening/closing mechanism is connected to the valve box. The tip of the valve is formed into a thin wall with a curved portion, and the valve has a curved portion that allows fresh concrete to flow smoothly onto the inner wall surface of a valve box that the thin tip comes into contact with during the opening operation of the three-way opening/closing valve. A valve seat is formed in the vicinity of the outlet at the bottom of the hopper, and has a sharp tip that a curved portion of the tip of the three-way valve comes into contact with during the closing operation of the three-way valve. The present invention provides a pump for compressing fresh concrete.

Effect According to the present invention having the above configuration, by opening and closing the three-way opening/closing valve installed at the bottom of the hopper in synchronization with the suction and discharge operations of the cylinder device that pumps the fresh concrete, the raw material put into the hopper is Concrete is drawn into the cylinder device through the valve box, and is discharged and continuously pumped through the outlet of the valve box. During the above operation, the tip of the three-way valve is formed into a thin wall having a curved portion, and a valve seat having a curve is formed on the inner wall surface of the valve box that the thin tip comes into contact with. Therefore, when the three-way opening/closing valve is opened, the thin-walled tip comes into contact with the curved valve seat at a certain angle, and the thin-walled tip pushes away the aggregate contained in the ready-mixed concrete. The valve seat, which has a sharp tip against which the curved portion of the tip of the three-way valve comes into contact, is placed at the bottom of the hopper by causing the flow to flow and letting it flow along the curved portion of the three-way valve and the valve seat. Because it is formed near the outlet, when the three-way on-off valve closes, the curved part of the tip of the three-way on-off valve comes into contact with the sharp tip of the valve seat at a certain angle, causing the valve to be contained in the ready-mixed concrete. By causing the aggregate to flow as if flying away and letting it escape along the curved part of the three-way on-off valve and the valve seat, it is possible to prevent the aggregate from being caught during the opening and closing operations of the three-way on-off valve. Since the suction and discharge can be switched continuously and smoothly, a three-way on-off valve can be used to prevent clogging of the ready-mixed concrete due to aggregate encroachment, resulting in smooth ready-mixed concrete production. It is possible to obtain a pump for pumping ready-mixed concrete that can continuously pump.

Embodiment An embodiment of the fresh concrete pressure pump according to the present invention will be described below with reference to the drawings.

FIG. 1 is a side sectional view showing one embodiment of the present invention, and FIG. 2 is a plan sectional view showing the main part cut away.

In the figure, reference numeral 1 denotes a hopper into which fresh concrete is charged, and a pair of valve boxes 2a and 2b are arranged below a bottom outlet 1a of the hopper 1. Further, near the bottom outlet 1a of the hopper 1,
Support shafts 3a, 3b are rotatably supported by the valve boxes 2a, 2b, and three-way open/close valves 4a, 4b are protruded from the support shafts 3a, 3b, respectively. Valve cylinders 5a, 5b are installed on the sides of the valve boxes 2a, 2b, and the rods 6a, 6b of the valve cylinders 5a, 5b and the support shaft 3
a and 3b are connected using support rods 7a and 7b. Therefore, as the rods 6a, 6b of the valve cylinders 5a, 5b expand and contract, the support shafts 3a, 3b rotate, thereby opening and closing the three-way valves 4a, 4b.

8 is a first concrete cylinder, which is connected to the valve box 2a, and 9 is a second concrete cylinder.
The concrete cylinder is connected to the valve box 2b. This first concrete cylinder 8 and second concrete cylinder 9
are connected by a connection box 10. Furthermore, a first hydraulic cylinder 11 and a second hydraulic cylinder 12 are attached to the connection box 10, and a piston rod 13 that protrudes and retracts from the respective hydraulic cylinders 11 and 12.
Pistons 14a and 14b with seal packings 20 are provided at the tips of pistons a and 13b. Therefore, by the operation of the first hydraulic cylinder 11 and the second hydraulic cylinder 12, the piston rods 13a,
13b and pistons 14a, 14b are set to alternately expand and contract inside the first concrete cylinder 8 and the second concrete cylinder 9. The pair of valve boxes 2a, 2b are provided with fresh concrete discharge ports 15a, 15b, and the opening edge 16a of the Y-shaped pipe 16 attached to the discharge ports 15a, 15b is a fresh concrete supply pipe (not shown). It is connected to the.

FIG. 3 is an enlarged sectional view showing the structure of the valve box 2a described above.
A three-way on-off valve 4 is mounted on a support shaft 3a rotatably supported by
A is provided protrudingly. The three-way on-off valve 4a is formed so as to become gradually thinner toward the tip 4c, and curved portions 4d and 4e are formed on both the front and back surfaces of this thin-walled portion. Furthermore, the three-way on-off valve 4a has the curved portions 4d and 4e formed therein.
The valve seat 2c has a convex portion on the inner wall surface (bottom) of the valve box 2a that the tip portion 4c comes into contact with during the opening operation of the valve box 2a. Forms adhesions. During the opening operation of the three-way on-off valve 4a, the tip portion 4c is connected to the curved portions 2e and 2f of the valve seat 2c.
near the joint or concrete cylinder 8
It is adapted to abut against the side curved portion 2f at a certain angle (preferably at a substantially right angle).

Further, a sharp tip 17a is formed near the bottom outlet 1a of the hopper 1.
7a forms a valve seat 17 which comes into contact with the curved portion 4d at a certain angle (preferably at a substantially right angle) when the three-way on-off valve 4a is closed. Furthermore, a curved portion 2g is formed on the inner wall of the upper corner of the valve box 2a near the valve seat 17 on the concrete cylinder 8 side as shown in the figure. Further, a sealing material 18 made of an elastic material such as urethane is fitted and fixed on the support shaft 3a, and when the sealing material 18 is worn out, it is moved toward the support shaft 3a in response to the rotation of a bolt (not shown) or the like. An elastic body such as urethane constituting the sealing material 18 can be freely drawn out. Furthermore, the distance L shown in FIG. 3, that is, the distance between the tip 4c of the three-way on-off valve 4a and the end on the piston 14a side of the valve box 2a, is determined to allow the aggregate contained in the fresh concrete to flow smoothly. It needs to be at least twice the diameter length.

The enlarged sectional view in Figure 3 is of the valve box 2.
Of the valve boxes 2a and 2b, only the structure of the valve box 2a is disclosed, but the structure of the other valve box 2a is disclosed.
A three-way opening/closing valve 4b and various curved portions having the same shape are also formed on portion b (not shown). Further, the hopper 1 itself is rotatable in the direction of arrow A integrally with the valve boxes 2a and 2b, and the tips of the concrete cylinders 8 and 9 can be opened.

The operation of the pump for pumping fresh concrete according to the present invention having such a configuration will be described below.

First, fresh concrete mixed with aggregate having a predetermined particle size is poured into the hopper 1, and then the valve cylinders 5a and 5b are activated. This valve cylinder 5
Since the rods 6a and 6b of a and 5b are set in advance to move in opposite directions, the support shafts 3a and 3b move in opposite directions in response to the movements of the support rods 7a and 7b. Rotate. Therefore, the opening and closing operations of the three-way on-off valves 4a and 4b protruding from the support shafts 3a and 3b are opposite to each other. That is, if one side is "open", the other side is "closed", and if one side is "closed", the other side is "open". On the other hand, the piston rods 13a, 13b of the first cylinder device 11 and the second cylinder device 12 move in and out of the three-way opening/closing valve 4.
This is done in synchronization with the opening/closing operations of a and 4b. Therefore, when the three-way on-off valve 4a closes the bottom outlet 1a of the hopper 1, as shown in FIG. 8
are in communication, and in this state piston rod 13
a extends to the left and discharges the ready-mixed concrete in the direction of arrow C, that is, in the direction of discharge port 15a. On the other hand, when the three-way on-off valve 4a opens the bottom outlet 1a of the hopper 1 and the hopper 1 and the concrete cylinder 8 are in communication as shown in FIG.
and the concrete cylinder 8 are shielded by a three-way on-off valve 4a, and in this state, the piston rod 13a contracts to the right and sucks the fresh concrete in the hopper 1 in the direction of arrow D, that is, into the concrete cylinder 8. ing. The above operations are performed continuously by the alternating operations of the pistons 14a and 14b sliding inside the first concrete cylinder 8 and the second concrete cylinder 9, so that the fresh concrete in the hopper 1 is discharged from the discharge port. It is continuously discharged via 15a and 15b.

During the above operation, when the three-way on-off valve 4a is opened, the tip 4c of the three-way on-off valve 4a (4b) is formed into a thin wall with curved parts 4d and 4e, and the tip 4c comes into contact with the valve. box 2a
Also provided on the inner wall surface (bottom) of the valve seat 2c is a valve seat 2c having a chevron-shaped cross section and a convex portion formed on both opposing surfaces of gently curved portions 2e and 2f. , curved portion 4d,
4e and the curved portions 2e and 2f of the valve seat 2c prevent the aggregate in the fresh concrete from being caught between the three-way valve 4a and the valve seat 2c. That is, the object flows smoothly in the curved portion, and even if the aggregate is likely to be caught, the tip portion 4c of the three-way valve 4a is thin, and the curved portion 2e of the valve seat 2c is , 2f or the curved part 2f on the concrete cylinder 8 side at a certain angle (preferably approximately right angle), the thin-walled part blows away the aggregate and makes it smooth. This promotes smooth flow and prevents the jamming phenomenon.

Furthermore, during the closing operation of the three-way on-off valve 4a, the curved portion 4
d comes into contact with the sharp tip 17a of the valve seat 17 formed near the bottom outlet 1a of the hopper 1 at a certain angle (preferably at a substantially right angle), so that the aggregate contacts the sharp tip 17a. It is blown away by the curved portion 4d and flows smoothly, and a curved portion 2g is also formed on the inner wall of the upper corner of the valve box 2a near the valve seat 17 on the concrete cylinder 8 side as shown in the figure. At the same time, since the distance L between the tip 4c of the three-way on-off valve 4a and the end of the valve box 2a on the piston 14a side is set to be more than twice the diameter of the aggregate used, this corner may become clogged with aggregate. Flows smoothly without any problems.

Note that the angle at which the tip 4c of the three-way valve 4a contacts the valve seat 2 and the angle at which the sharp tip 17a contacts the curved portion 4d are preferably approximately right angles, but approximately 60 degrees. If the angle is between 120 degrees and 120 degrees, the aggregate can be effectively blown away, the aggregate can be smoothly flowed and released, and clogging can be prevented.

It goes without saying that the same effect can be achieved in the case of the three-way on-off valve 4b.

In this embodiment, two cylinder devices and three-way on-off valves 4a and 4b are used to alternately and simultaneously suck and discharge fresh concrete. It is also possible to have a configuration of three or more.

Effects of the Invention As explained in detail above, the fresh concrete pressure pump according to the present invention has a three-way opening/closing valve having a front end that is curved on both the front and back sides, which is in contact with the inner wall of the valve box disposed at the lower part of the hopper. A valve seat is formed into a thin-walled shape having a thin-walled shape and has a curved portion that allows fresh concrete to flow smoothly on the inner wall surface of the valve box that the thin-walled tip comes into contact with during the opening operation of the three-way on-off valve. Since a valve seat having a sharp tip that comes into contact with the curved tip of the three-way opening/closing valve during the closing operation is formed near the bottom outlet of the hopper, the following effects can be achieved. In other words, even when used in civil engineering work etc. where fresh concrete contains a large amount of aggregate, there will be no accidents where the aggregate gets caught between the three-way valve and the valve seat when the three-way valve is opened and closed, and the aggregate content will be reduced. It is possible to eliminate the dehydration symptoms of fresh concrete caused by the clogging phenomenon and the clogging phenomenon caused by the stoppage of discharge. Therefore, it is possible to constantly supply fresh concrete containing aggregate smoothly, and the three-way valve can be used to switch between intake and discharge of ready-mixed concrete.
An efficient fresh concrete pump can be obtained. Furthermore, according to the present invention, the same effects can be obtained even if the shape of the pump itself and the valve box itself are made smaller, so there is no need to increase the size of the device. This method has the advantage that it is possible to reduce the cost required for manufacturing the device, so it is particularly effective when applied to a pump for pumping fresh concrete containing aggregate.

[Brief explanation of drawings]

Fig. 1 is a side sectional view showing an embodiment of a pump for pumping fresh concrete according to the present invention, Fig. 2 is a sectional view taken along - in Fig. 1, and Fig. 3 is an enlarged view of the main parts of the present invention. FIG. 4 is an enlarged cross-sectional view showing the operating state of the main parts of the present invention. 1...Hopper, 2a, 2b...Valve box, 2c...Valve seat, 2e, 2f, 2g...
...Curved portion, 3a, 3b... Support shaft, 4a, 4b...
Three-way opening/closing valve, 4c... tip, 4d, 4e... curved part, 5a, 5b... valve cylinder, 8... first concrete cylinder, 9... second concrete cylinder, 10... connection box, 11...Hydraulic cylinder, 12...Hydraulic cylinder, 13a, 13
b... Piston rod, 14a, 14b... Piston, 15a, 15b... Discharge port, 16... Y-shaped pipe, 17... Valve seat, 18... Seal material,
20... Seal Patsukin.

Claims (1)

[Claims] 1. A three-way opening/closing valve is disposed at the bottom outlet of the hopper into which fresh concrete is introduced, and a valve box arranged at the lower part of the hopper is communicated with the hopper, while a cylinder device for pressurizing the fresh concrete is connected to the valve box. In the pump for pumping fresh concrete, the cylinder device is connected to a cylinder device for alternately sucking and discharging fresh concrete. A valve seat having a curved part that allows fresh concrete to flow smoothly is formed on the inner wall surface of the valve box with which the thin-walled tip comes into contact when the three-way opening/closing valve is opened, and the three-way opening/closing valve contacts the inner wall surface of the valve box when the three-way opening/closing valve is closed. 1. A pump for pumping fresh concrete, characterized in that a valve seat having a sharp tip against which a curved portion of the tip of an on-off valve comes into contact is formed near the bottom outlet of the hopper.