JPH0440166B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is capable of centrifugally forming the ready-mixed concrete filled in the formwork into a cylindrical shape by rotating a cylindrical formwork and using the centrifugal force of the rotation. The present invention relates to a centrifugal concrete pipe manufacturing apparatus.

(Prior art) In the centrifugal pipe manufacturing method in which a cylindrical formwork is rotated at high speed and the centrifugal force is used to manufacture concrete pipes, the aggregate with a high specific gravity in fresh concrete is used as the outer layer of the concrete pipe to be formed. It is possible to form a concrete pipe with a high concentration of mortar components on the inner layer side, and when used for sewer pipes, for example, there is an advantage that water permeability can be kept low.

Conventionally, as an example of this type of centrifugal concrete pipe manufacturing apparatus, there is one shown in FIGS. 5 and 6. In this conventional centrifugal concrete pipe manufacturing apparatus, In addition, a cylindrical form C is placed in a horizontal position on the upper part between two rotating bodies B, B which are erected horizontally at a predetermined distance from each other, and each of the rotating bodies B, B and the form C are The mold C is configured to be able to rotate in a direction opposite to the rotational direction of the rotating body B by the frictional force between them. When this formwork C is rotated, the ready-mixed concrete Z filled inside the formwork is sequentially formed into a cylindrical shape by centrifugal force, but during operation, a worker is rotating a long spatula. The concrete pipe is inserted into the formwork C, and the work of leveling the thickness of the fresh concrete Z and smoothing the inner surface of the concrete pipe to be formed is performed.

However, the conventional concrete pipe manufacturing apparatus shown in FIGS. 5 and 6 has the following problems.

(1) Since the formwork C is simply placed on the upper part between the two rotating bodies B and B, the formwork C tends to vibrate up and down between the rotating bodies B and B during operation (so-called dancing). There was a risk that the formwork C would fall off from between the rotating bodies B and B during operation.

(2) The formwork dancing phenomenon described in (1) above becomes more pronounced as the rotational speed of the formwork C increases.
The rotational speed of the formwork C can only be increased to a certain level (safe rotational speed), and the separation of the aggregate and mortar components in fresh concrete due to centrifugal force can only occur to a certain extent, so that the concrete that is formed is The density of the mortar component on the inner layer side of the pipe can only be increased to a certain extent, and it takes a long time to form the concrete pipe.

(3) In concrete pipes that have a socket, the socket is relatively easy to break, but in the conventional method of manufacturing concrete pipes (Figures 5 and 6), concrete ingredients are concentrated in the socket of the concrete pipe. The density of the socket cannot be increased, and the strength of the socket cannot be increased.

(4) Manual work is required to level the inner surface of the concrete pipe during operation, and the work is dangerous.

(5) The inner surface of the concrete pipe to be formed is only leveled manually (leveling work with a long spatula), so the smoothness of the inner surface of the pipe is poor.

(Objective of the Invention) In view of the problems of the conventional centrifugal concrete pipe manufacturing apparatus described above, the present invention has been developed to be able to perform pipe manufacturing work safely and automatically, and to form high-density concrete pipes in a short time. It is an object of the present invention to provide a centrifugal concrete pipe manufacturing apparatus that can increase the strength of a relatively fragile socket part and improve the smoothness of the inner surface of the concrete pipe.

(Means for Achieving the Object) The centrifugal concrete pipe manufacturing apparatus of the present invention opens an opening on the spigot side in an annular space formed between an inner cylinder and an outer cylinder surrounding the outside thereof, and A double formwork whose socket side opening is closed with a lid material is used, and a rotary table on which the double formwork can be placed vertically with the socket side facing downward is rotated at high speed by a power device. A formwork rotation drive device capable of rotationally driving a double formwork in a vertical position;
a formwork posture holding device for holding the double formwork in a vertical position from the periphery of the double formwork on the rotary table; and a spigot in the annular space of the double formwork erected on the rotary table. There is a ready-mixed concrete charging device that can charge fresh concrete into the annular space from a side opening, and a ready-mixed concrete charging device that is installed above the double formwork installed on the rotary table and which allows the raw concrete to be poured into the annular space from the exit of the ready-mixed concrete charging device. The present invention is characterized by comprising a ready-mixed concrete pushing device that can push the ready-mixed concrete supplied to the spigot side opening into the annular space.

(Function) The centrifugal concrete pipe manufacturing apparatus of the present invention installs a double formwork on a rotary table in a vertical position with its socket side facing downward, and uses a formwork posture holding device to move the double formwork away from its surroundings. It is held in a vertical position, and the ready-mixed concrete is poured into the annular space of the double formwork from the spigot side opening in the annular space by the ready-mixed concrete feeding device, and the ready-mixed concrete is further pushed into the annular space by the ready-mixed concrete pushing device. Thereafter, a concrete pipe can be centrifugally formed within the double formwork by rotating the double formwork at high speed in the vertical position using a formwork rotation drive device.

Therefore, according to the centrifugal concrete pipe manufacturing apparatus of the present invention, since the double formwork is installed on the rotary table in a vertical position with the socket side facing downward, the double formwork is placed in the annular space of the double formwork. Due to its gravity, fresh concrete moves downward (socket side)
density increases.

In addition, the double formwork installed on the rotating table,
Since the formwork is held vertically by the formwork posture holding device, the rotation speed of the double formwork is faster than that of the conventional method (horizontal type shown in Figures 5 and 6). This makes it possible to rotate the concrete, promoting the separation of the aggregate and mortar components in the fresh concrete.

Furthermore, since the ready-mixed concrete pushing device can push the ready-mixed concrete into the annular space of the double formwork, the density of the ready-mixed concrete filled into the annular space can be increased.

(Embodiment) A preferred embodiment of the present invention will be described with reference to FIGS. 1 to 4. In the centrifugal concrete pipe manufacturing apparatus of this embodiment, an inner cylinder 11 and an outer cylinder 12
The socket side opening 13b of the annular space 13 formed between the inner and outer cylindrical bodies 11 and 12 is connected to the lid member 1.
A double formwork 1 which is closed with 4 is used.

This centrifugal concrete pipe manufacturing apparatus includes a framework 80 consisting of columns 82 erected at each of the four corners of a pedestal 81 having an appropriate area, and a rotary table 22 on which the double formwork 1 can be placed vertically. A formwork rotation drive device 2 that can be rotated at high speed by a motor 21, and a formwork posture holding device that holds the double formwork 1 placed on a rotary table 22 in a vertical position from its periphery. 3, a ready-mixed concrete charging device 4 for charging fresh concrete into the annular space 13 of the double formwork 1 placed on the rotary table 22, and an annular space 1 of the double formwork 1.
a ready-mixed concrete pushing device 5 for pushing the ready-mixed concrete supplied into the spigot-side opening 13a of No. 3 into the annular space 13; and a vibrator device 6 for giving slight vibrations to the double formwork 1 erected on the rotary table 22. It is configured with.

Several types of double formwork 1 with different diameters can be adopted. Further, a socket forming portion is provided at one end side of the double formwork 1. Both inner and outer cylinders 1
A spigot side opening 13a of an annular space 13 formed between 1 and 12 is open, and a socket side opening 13b of the annular space 13 is closed with a lid member 14 that is detachable from the outer cylinder 12. There is. This lid material 14 is formed into a disk shape considerably larger than the outer diameter of the outer cylinder body 12, and on the outer peripheral surface of the lid material 14 is provided a lower roller 32 of a formwork posture holding device 3, which will be described later.
B and 32B are designed to be in contact with each other. The lid material 14 has an appropriate size (diameter) depending on the thickness of the double formwork 1 used. Further, on the lower surface of this lid member 14, there is a formwork positioning projection (described later) 2 formed on the upper surface of the rotary table 22.
A recess 15 that fits into the recess 4 is formed. The formation position of the recessed portion 15 is set to be located further outward in the radial direction as the thickness of the double formwork 1 used increases. Further, on the spigot side of the double formwork 1, a circular annular plate 16 is detachably fixed to the outer cylinder 12, and an upper roller of a formwork posture holding device 3, which will be described later, is attached to the outer peripheral surface of the annular plate 16. 32A,
32A is designed to make a transition contact. Note that the size of this annular plate 16 also changes depending on the size of the double formwork 1.

The rotary table 22 of the formwork rotation drive device 2 is supported by a bearing 23 on a pedestal 81, and is rotated by a motor 21 via a belt 25. The rotational speed of the motor 21 is adjustable, and the double formwork 1 placed on the rotary table 22 can be rotated at a very low speed or at a high speed. A plurality of formwork positioning protrusions 24, 24, . When placed, the recess 15 on the lower surface of the mold cover 14 fits into any of the protrusions 24 on the upper surface of the rotary table 22 in the radial direction. Note that when the recess 15 and the protrusion 24 are fitted, the rotation center of the rotary table 22 (center line P-
P) and the center of the double formwork 1 are made to coincide.

The formwork posture holding device 3 includes an upper guide 30A that holds the spigot side of the double formwork 1 placed on the rotary table 22 with the socket side facing downward, and an upper guide 30A that holds the spigot side of the double formwork 1 placed on the rotary table 22 with the socket side facing downward; a lower guide 30B that holds the double formwork 1 from the side, and an upper guide 3 that prevents the double formwork 1 from floating upward.
It is equipped with 0C.

The upper guide 30A and the lower guide 30B each have a total of four support arms 31A, 31A...31.
B, 31B... are provided with rollers 32A,
32B, and the support arms 31A and 3 with rollers are attached.
The base ends of the molds 1B are fixed to support columns 82, 82, . Each of the upper and lower support arms 31A, 31B is
Each roller 32A, 32B is swingable or expandable so that it can move horizontally toward the rotation center line P-P of the rotary table 22, and the size of the annular plate 16 of the double formwork 1 or the lid material 14 is adjusted. Accordingly, the width of each roller 32A, 32B can be adjusted. Also, the upper and lower support arms 31A, 31
The rollers 32A and 32B are in contact with the outer peripheral surfaces of the annular plate 16 and the lid member 14, respectively, so that their swinging or expansion/contraction can be restricted.

The upper surface guide 30C is a vertical bar-shaped presser member 3.
5 is rotatably held in a housing 70, which will be described later, and is biased downward by a spring 36. This presser member 35 is installed concentrically with the rotation center line PP of the rotary table 22, and the annular plate 1 fixed to the upper inner surface of the formwork inner cylinder 11 on the lower surface of the presser member 35.
By pressing 7 from above, the entire double formwork 1 is urged downward.

The formwork posture holding device 3 is configured as described above, and the double formwork 1 can be reliably held in a vertical posture on the rotary table 22 by the upper guide 30A, the lower guide 30B, and the upper surface guide 30C. It's summery.

The ready-mixed concrete feeding device 4 feeds the ready-mixed concrete Y from the ready-mixed concrete pressure feeders 41, 41 through the supply pipes 42, 42 and into the annular space 13 of the double formwork 1.
It is configured so that it can be supplied to the spigot side opening 13a in. Fresh concrete pressure feeder 41
A total of 6 units are used in this embodiment, and fresh concrete is supplied to the spigot side opening 13a of the annular space 13 through flexible supply pipes 42, 42... (total 6 pipes). There is. The outlets 42a, 42a of the supply pipes 42, 42 are the upper (spigot side) opening 1 of the formwork annular space 13.
It is located at approximately the same position in the radial direction as the outer edge of 3a.

The fresh concrete pushing device 5 has a total of six block bodies 56, 56, each equipped with two pushing rods 59, 59, and three block bodies 56 each.
A pair of left and right cylinders 54, 54 for moving forward and backward in the radial direction together with each push rod 5.
A push-down mechanism 60 that acts to push down 9, 59...
It is equipped with

This fresh concrete pushing device 5 is a double formwork 1
Above the housing 70, the housing 70 is supported to be vertically movable with respect to the framework 80. The casing 70 is guided by a total of four guide rods 83, 83, . It's summery.

The pair of cylinders 54, 54 are connected to the rotary table 2.
They are respectively attached to the outer surface of the side wall of the housing 70 at positions facing each other across the rotation center line PP of the two. Rod 54 of each cylinder 54, 54
a projects into the housing 70, and a horizontally long block mounting base 55 is attached to the tip of the rod 54a.
is installed. Three block bodies 56, 56, 56 are attached to each side of the mounting base 55, respectively. These three blocks 56,5
Among the blocks 6 and 56, one block 56 located in the center is fixed to the mounting base 55 with the mounting angle unchanged, and the other two blocks 56 on the left and right are
6 and 56 are each mounted so that it can swing freely within a horizontal plane and can be fixed at an appropriate mounting angle. Two left and right rollers 66, 66 are provided at the lower end of the inner surface of each block body 56, 56.... These rollers 66, 66 come into contact with the outer surface of the upper end of the inner cylindrical body 11 of the double formwork 1, and the block body 56 is set in an appropriate position and posture.

Block bodies 56, 5 on each side, each consisting of three blocks
The outlet 42a of each fresh concrete supply pipe 42, 42 is fixed to one of the pipes 6, 56, respectively.

Two vertical holes 57, 57 are formed in each of the block bodies 56, 56, . The upper portion of each of the push rods 59, 59 protrudes upward by a considerable length range (for example, about 200 mm) from the upper surface of the block body 56, and the upper end head 59a of the push rod 59 and the block body 56
A spring 58 for pushing up the push rod is provided between the top surface and the push rod.
is interposed. The push rod 59 is urged upward by the spring 58 in its natural state, and is set so that the lower end 59b of the push rod 59 is located at a height slightly above the height of the supply pipe outlet 42a. has been done.

Each of the blocks 56, 56... has a thickness of the double formwork 1 used (for example, the number 1 in FIG. 2).
For small diameter as shown by 1' or for large diameter as shown by chain line 1'), each push rod 5 is
9, 59... are the annular spaces 13 of the double formwork 1, respectively.
The cylinders 54, 54 are adjusted to expand and contract, and the mounting angles of the four swingable block bodies 56, 56... are adjusted so that the cylinders 54, 54 are positioned directly above the upper opening 13a.

The push-down mechanism 60 includes two motors 61, 6.
Each push rod 59, 59...
It is constructed by attaching a single push plate 63 having an area that covers the top (total of 12 pieces). Then, by operating the motors 61, 61, the support rod 6
2 and 62, the push plate 63 moves up and down, and when the push plate 63 moves upward, it does not act on the push rods 59, 59, etc., as shown in solid lines in FIG.
As shown by a chain line 63', when the push plate 63 moves downward, the lower surface of the push plate 63 pushes down the upper ends of the push rods 59, 59, . . . , respectively. Also, the push plate 63
When moving downward, the lower end 59 of each push rod 59, 59...
b is designed to penetrate into the upper opening 13a of the formwork annular space 13 to a certain depth, as indicated by a chain line 59b' in FIG.

This ready-mixed concrete pushing device 5 is activated at the same time as ready-mixed concrete is poured into the annular space of the formwork, and the ready-mixed concrete Y discharged from the outlet 42a of the supply pipe 42 is sequentially pushed into the annular space 13 by pushing rods 59, 59... It acts to push downward. Furthermore, when pouring the fresh concrete Y into the upper opening 13a of the annular space 13, the aggregate in the fresh concrete may become clogged near the upper opening 13a as indicated by the symbol Ya, but the pushing rods 59, 59... is continuously moved up and down, so that the aggregate Ya stuck near the upper opening 13a can be automatically pushed downward into the annular space 13. The ready-mixed concrete Y used in this example is a hard one with a small slump (moisture content); Even in this case, by operating the fresh concrete pushing device 5, the fresh concrete Y can be smoothly pushed downward into the formwork annular space 13, and the density of the fresh concrete in the annular space 13 can be increased. .

The vibrator device 6 is provided in the lower guide 30B portion of the formwork posture holding device 3. This vibrator device 6 has a box shape and is interposed between each lower support arm 31B, 31B... and each lower roller 32B, 32B.... These vibrator devices 6, 6... are activated simultaneously when the ready-mixed concrete Y is put in, and by slightly vibrating the socket part of the double formwork 1, the ready-mixed concrete Y put into the annular space 13 is smoothly moved downward. It has the effect of increasing the density of the fresh concrete Y in the annular space 13 (particularly in the socket part).

Next, to explain how to use this centrifugal concrete pipe manufacturing apparatus, when setting the double formwork 1 on the rotary table 22, lift the casing 70 upwards and place the upper guide 30A and lower part 30B on each support. With the arms 31A and 31B open, the double formwork 1 is placed on the rotary table 22 in a vertical position with the socket side facing downward, and then the upper guide 3
0A, lower guide 30B and upper guide 30C
(moves the housing 70 downward) to the formwork holding position. Then, at the same time as the ready-mixed concrete feeding device 4 supplies the ready-mixed concrete Y, the ready-mixed concrete pushing device 5 and the vibrator device 6 are operated to fill the ready-mixed concrete Y into the annular space 13 of the formwork. By supplying the ready-mixed concrete Y while operating the ready-mixed concrete pushing device 5 and the vibrator device 6 in this manner, the filling density of the ready-mixed concrete into the annular space 13 is increased. In particular, since the double formwork 1 is set in a vertical position with the socket side facing downward, the density of the fresh concrete in the socket part in the annular space 13 increases due to the weight of the fresh concrete Y, and the socket in the concrete pipe to be formed increases. The strength of the parts can be increased. When filling the ready-mixed concrete into the formwork annular space 13 is completed, the supply of ready-mixed concrete is stopped, the operation of the ready-mixed concrete pushing device 5 and the vibrator device 6 is also stopped, and then the formwork rotation drive device 2 is activated. to rotate the double formwork 1. At first, the double formwork 1 is rotated at a very low speed to equalize the density of the fresh concrete Y in the annular space of the form, and then the rotary table 22 is rotated at high speed to spread the fresh concrete Y within the double formwork 1.
is centrifugally formed into a concrete pipe. At this time, since the double formwork 1 is reliably held by the formwork posture holding device 3, the rotary table 22 (double formwork 1) can be used in the conventional horizontal centrifugal molding method. By rotating the double formwork 1 at a higher speed than before, the aggregate with a high specific gravity in the ready-mixed concrete Y is transferred to the outside in the thickness direction of the concrete pipe to be formed. The separation of the aggregate and mortar components is promoted so that the mortar components are concentrated on the inner side in the pipe thickness direction. When the mortar component becomes concentrated on the inner surface of the concrete pipe formed in this way, the inner surface of the concrete pipe becomes finely smooth, and the permeability of water during use of the concrete pipe is reduced, improving quality. Further, by rotating the double formwork 1 at high speed in this manner, the time required for centrifugal forming of the concrete pipe can be shortened. and,
After performing centrifugal molding for a predetermined period of time, the mold rotation drive device 2 is stopped to complete the centrifugal molding operation. Double formwork containing concrete pipes after centrifugal forming 1
is removed from this concrete pipe manufacturing equipment,
After moving to the curing process, the double formwork 1 may be dismantled to take out the concrete pipe. Incidentally, the spigot side end of the formed concrete pipe is corrected in a subsequent process if necessary.

(Effects of the Invention) The centrifugal concrete pipe manufacturing apparatus of the present invention has the following effects.

(1) Since the double formwork 1 is centrifugally formed in a vertical position with the socket side facing downward, the formwork annular space 1
The fresh concrete Y filled in the pipe 3 flows down under its own weight, increasing the density of concrete filling in the socket portion, and increasing the strength of the relatively fragile socket portion of the concrete pipe.

(2) Since the double formwork 1 is held in a vertical position from its surroundings by the formwork posture holding device 3, the double formwork 1 does not fall off from the rotary table 22, increasing safety. Furthermore, it is possible to rotate the double formwork 1 at a higher speed than in the case of conventional horizontal concrete pipe manufacturing equipment, so that the aggregate in the ready-mixed concrete Y filled in the formwork annular space 13 is rotated on the outside. Separation is promoted so that the mortar components gather on the inside, and the inner surface of the concrete pipe to be formed can be finished finely and smoothly, and the permeability of water from the inner surface of the concrete pipe can be kept low.

(3) It is equipped with a ready-mixed concrete pushing device 5 that can push the ready-mixed concrete Y supplied from the outlet 42a of the ready-mixed concrete charging device 4 to the spigot side opening 13a of the formwork annular space 13 into the annular space 13. , it is possible to fill the formwork annular space 13 with fresh concrete Y at a high density, and form a high-strength concrete pipe. Even if the spigot side opening 13a gets clogged,
The packed aggregate can be forced into the annular space 13, and the ready-mixed concrete Y can be smoothly filled into the annular space 13.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of a centrifugal concrete pipe manufacturing apparatus according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of FIG. 1, and FIG. 3 is a partial perspective view of the concrete pipe manufacturing apparatus of FIG. 1. 4 is a partially enlarged cross-sectional view of FIG. 1, FIG. 5 is a front view of a conventional centrifugal concrete pipe manufacturing apparatus, and FIG. 6 is a cross-sectional view of FIG. 1... Double formwork, 2... Formwork rotation drive device, 3
...Formwork posture holding device, 4...Ready-mixed concrete charging device, 5...Ready-mixed concrete pushing device, 6...
Vibrator device, 11... Inner cylinder body, 12... Outer cylinder body, 13... Annular space, 13a... Spigot side opening, 13b... Socket side opening, 14... Cover material, 21... Power device (motor ), 22... rotary table, 41... pressure feeder, 42... supply pipe, 4
2a...exit, Y...ready concrete.

Claims (1)

[Claims] 1 Inner cylindrical body 11 and outer cylindrical body 12 surrounding the outside thereof
A double formwork 1 is used in which a spigot side opening 13a in an annular space 13 formed between the two is open and a socket side opening 13b of the annular space 13 is closed with a cover material 14. A formwork rotation drive in which the double formwork 1 can be rotated in a vertical position by rotating a rotary table 22, which can be placed in a vertical position with the side facing downward, at high speed by a power unit 21. a device 2, a formwork posture holding device 3 for holding the double formwork 1 in a vertical position from the periphery of the double formwork 1 on the rotary table 22; A ready-mixed concrete charging device 4 capable of charging fresh concrete Y into the annular space 13 from the spigot side opening 13a in the annular space 13 of the double formwork 1, and a double formwork 1 installed on a rotary table 22. a ready-mixed concrete pushing device 5 installed above and capable of pushing the ready-mixed concrete Y supplied into the spigot side opening 13a of the annular space 13 from the output 42a of the ready-mixed concrete charging device 4 into the annular space 13; Centrifugal concrete pipe manufacturing equipment characterized by: