JPH0244684B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method and apparatus for manufacturing fiber-reinforced cement boards of fixed dimensions using a so-called premix mortar, which is a mortar in which cement, sand, water, and reinforcing fibers such as glass fibers are mixed in advance. Low tensile strength and low bending strength were cited as a drawback of cement products, but in order to improve this, a method was developed to dramatically strengthen the cement by evenly dispersing glass fibers, synthetic resin fibers, etc. into cement mortar. It has been known. In this case, there are two methods for dispersing reinforcing fibers (hereinafter simply referred to as fibers) into cement mortar: the direct spray method and the premix method.The premix method is better for mass production in terms of productivity and working environment. It is considered to be suitable. The premix method is a method of manufacturing cement products by mixing cement, sand, water, and fibers in advance, pouring this mortar into a mold, curing it, and removing it from the mold. This method eliminates the drawbacks of the direct spray method, but because the pre-mixed fibers are dispersed three-dimensionally and have no directionality, the fibers that work effectively as reinforcement elements for tensile strength and bending strength are The fibers are only a small part of the fibers, and most of the fibers are just helplessly intervening. A prior art technique that attempts to solve this drawback and two-dimensionally orient the direction of the fibers mixed in premix mortar is ``Method and device for supplying reinforcing fiber premix mortar'' (Japanese Patent Laid-Open Publication No. 105303/1982).
can be given. This technology involves placing a belt conveyor underneath a mortar container with its bottom open so as to close the opening surface, and continuously delivering the premixed mortar loaded into the mortar container in a strip shape. It is characterized by being mechanically smoothed, gradually thinned and continuously supplied to a formwork or the like. What is disclosed as a specific method for mechanically smoothing the mortar is applying vibration to the band-shaped mortar and repeatedly hammering it from the upper side, and the device is a smoother (pounding mechanism) that smoothes the upper surface. A vibration guide plate comprising a vibrator and a vibrator is disclosed in a limited manner. By the way, among this technology, a belt conveyor is installed under a container whose bottom surface is open so as to close the opening surface, and the contents loaded in the container are continuously delivered in a fixed amount. This is a conventional method used to transport foundry sand, and cannot be called a particularly new technology. Therefore, it is thought that the feature of this prior art is that the delivered strip-shaped mortar is mechanically smoothed, gradually thinned, and then continuously supplied to a formwork or the like. By the way, according to an example specifically disclosed for mechanical smoothing, the rotation speed of the disk that converts the vertical movement of the smoother (beating) is about 120 rpm, and the vibration frequency of the vibrator is 2900 vpm. It is becoming. In actual work, this level of vertical movement requires only a small number of strikes, which results in uneven thickness between the areas of the strip mortar that have been struck and those that have not, and this unevenness causes vibrations to be applied on the vibration guide plate. This results in equalization, but a difference in thickness is now created between the center and both ends of the strip of mortar. Moreover, depending on the formulation, the moisture content may separate, causing the mortar to lose its fluidity and prevent the fibers from aligning in two dimensions.
It even becomes flamboyant in the mortar. These drawbacks do not pose much of a problem when applied to pouring into a three-dimensional formwork as illustrated in the prior art (from the diagram, it seems to be manufacturing a concrete U-shaped groove). Dew. In such applications, even if all the fibers are supplied with accurate two-dimensional alignment, as they flow down three-dimensionally within the mold, they will be considerably disturbed and their three-dimensional orientation will be distorted. This is because it is expected that it will collapse. In other words, in this known technique, the purpose of feeding the mortar and its beating action is not to form it into a strip, but to two-dimensionally align the orientation of the fibers that are irregularly mixed in the mortar. However, if a mortar layer is dropped and filled into a three-dimensional mold, the fibers that have been carefully oriented will become scattered again. However, if the product is directly used as a flat plate molded product, there is a concern that undesirable development such as the above-mentioned surface unevenness and uneven distribution of fibers will occur. However, if the formwork is intended for the production of flat plates, the drawbacks will become obvious as a decrease or variation in physical properties. In this case, the fibers are oriented in a plane to dramatically improve tensile strength and bending strength, thereby greatly increasing the significance of developing fiber-reinforced cement, which aims to dramatically reduce the thickness of cement plates. This is because it means going backwards. The purpose of this invention is to provide a mortar supply method most suitable for manufacturing a cement plate and a device used therefor, while giving a tentative evaluation to the features and effects of the prior art, and focusing on its shortcomings. shall be. For this purpose, the present invention provides a method in which mortar, in which cement, sand, water, and fibers are mixed in advance, is stored in a mortar container with a cutout in the bottom, and the mortar is placed on a belt conveyor that communicates with the cutout. The cement is discharged out of the container in fixed amounts and subjected to two repeated high-speed beating actions with different strokes to form a mortar band with uniform width and thickness, and the cement is aligned and placed on the guide plate at the tip of the belt conveyor. At the same time, the tip of the strip is inserted into the inner edge of the front partition plate of the board formwork, and at the same time, all equipment including the belt conveyor is retreated in synchronization with the advancement of the strip, and the strip is placed on the belt conveyor into the formwork. The technical means is to cut off the rear partition plate at a length that matches the inner edge of the rear partition plate, and fit the strip into the recess partitioned by the formwork partition plate. To explain the configuration of this invention using figures, the first
The figure is a front sectional view of the device according to the present invention, and FIG. 2 is a conceptual plan view. In FIGS. 1 and 2, reference numeral 1 designates a mortar container, and the shape is, for example, a square solid with a rectangular cross section, with a notch 11 provided in a certain area of the bottom and a notch 12 also provided on the side surface connected to it. . The adjustment plate 13 is slidably attached to the side surface so as to cover the notch 12, and can be fixed at a desired position. on the other hand,
A belt conveyor 2 is connected so as to close the notch 11 at the bottom, and this belt conveyor 2 consists of a horizontal part 21 extending from the bottom of the mortar container 1 and a slope part 22 extending further beyond that. There is. The belt conveyor 2 is endlessly wrapped around a drive pulley 23 at one end and a guide pulley 24 at the other end. Horizontal part 2 of belt conveyor
Two shielding plates 3, which can be freely adjusted to a desired width, are erected on the upper surface of the conveyor belt 1 so that the bottom surface of the shielding plates 3 slides on the belt conveyor 21. Further, a pair of levelers 4 and 5 having a width selected to occupy the entire width formed by the two shielding plates 3 are interposed between the shielding plates 3 and 3. The leveling devices 4 and 5 operate by converting the rotational force of the drive motor 6 through the crank arm into vertical movement of leveling bodies 41 and 51 at the tips. However, the strokes of both vertical movements can be changed into various combinations by adjusting the intermediate turnbuckles 42, 52. For example, the stroke of the thrusting body 41 can be set to twice that of the thrusting body 51. The location where the leveler 5 is set is at the end of the horizontal section 21 of the belt conveyor, and also at the boundary where it moves to the inclined section 22. A stop plate 7 is interposed between the levelers 4 and 5, and a device connecting them upwards allows them to be moved up and down as desired. These mortar container 1, belt conveyor 2,
The shield plate 3, the levelers 4 and 5, the drive motor 6, the stop plate 7, and all the members related to these operations are integrated into a frame and hung on a traveling frame,
The entire device is constructed so that it can be driven forward, backward, left and right. Since the apparatus of the present invention has the structure as described above, first, a required amount of premix mortar PMO containing appropriate amounts of cement, sand, water, and fibers is stored in the mortar container 1. In this state, when the drive pulley 23 starts rotating, the belt conveyor 2 starts driving and tries to convey the PMO out of the mortar container from the notches 11 and 12 on the bottom and side surfaces, but it is difficult to position it at an appropriate height. Since the adjustment plate 13 that is set prevents this, only a certain amount is constantly cut out. This premix mortar PM1 is subjected to the leveling operation of levelers 4 and 5 which are successively activated between the two shielding plates 3 and 3 on the horizontal section 21 of the belt conveyor. These two levelers level the top surface of the PM1 by converting the rotational force of the drive motor 6 into vertical motion, and combine this with the progress of the belt conveyor to level the surface and keep the thickness constant. There is an action to do this. The vertical movement is preferably at least 250 times/minute or more, and the vertical stroke of the thruster 5 is, for example,
When it is 20m/m (that is, this is the thickness of the cement product), the vertical stroke of the leveler 4 is 40m/m, and the adjustment plate 13 upstream thereof is 40m/m.
This can be determined empirically based on the product dimensions (thickness and width), such as setting the opening of 60m/m. As described above, by repeatedly applying the leveling operation in two stages at high speed, the top surface of PM1 becomes extremely smooth.
Moreover, the thickness and width form a band-like body that is extremely precise, and inside the band, the blended fibers are oriented two-dimensionally in the X and Y directions, instead of being three-dimensionally non-directional in the container. . The premixed mortar PM2, which has passed through the leveler 5 while being shaped into an even width and thickness, is conveyed while maintaining its shape on the belt conveyor slope 22, and is conveyed to the tip provided along the end of the belt conveyor. It is transferred from the plate 25 so as to fit exactly into the inner edge of the front partition plate 81 of the flat formwork 8 to form PM3.
FIG. 3A is an explanatory illustration of the state in which transfer is about to occur; at this moment, a preset timer is activated, and the entire device begins to retreat from the tip plate 25 so that it has an even width and thickness. Ta
PM2 is supplied to fill the recesses 83 of the flat frame in just the right amount. During this time, unlike the prior art, there is no variation in the thickness or width of the mortar strip due to vibration, and there is no fear that moisture will separate and float to the surface, resulting in uneven content. The two-dimensionally oriented fibers are simply transferred to the mold without any disturbance. FIG. 3C shows a state in which the shielding plate 3 descends from above the outflowing PM1 after the calculated time has elapsed, reaches the surface of the belt conveyor horizontal section 21, and blocks the subsequent outflow of PM1. Belt conveyor inclined section 2
The length of the mortar strip PM2 left on the flat formwork 8 is set equal to the length of the recess 83 left on the flat formwork 8. (Both lengths are l.) At this time, the levelers 4 and 5 stop. Transfer all of the PM2 to the recesses of the flat formwork 8 without too much or too little, and finish fitting it exactly to the inner edge of the rear partition plate 82 of the flat formwork.
When it reaches PM3, all driving of the belt conveyor 1 and retraction of the entire device are stopped. In this way, the purpose is to drive and stop the belt conveyor 2, drive and stop the levelers 4 and 5, actuate the stop plate 7, and drive the belt conveyor tip plate 25 backward and stop it by reversing the entire device. The synchronization and control can be performed by setting a timer according to the thickness and width of the cement plate to be used. The apparatus used only for this invention will be explained in more detail with reference to the drawings. FIG. 4 is a front view showing a specific embodiment for making the band-shaped mortar PM2 of the present invention, and FIG. 5 is a side view thereof. Drive motor 6
The rotational force is transmitted to the sprocket wheel 62a via the chain 61a and rotates the connecting shaft 63. This connecting shaft 63 is attached to a bearing 64 in the frame 9 of the entire device.
A crank arm 65a is fitted to the tip of the connecting shaft 63. crank arm 65
On the side opposite to the fitting part, there is a protrusion that is eccentric to its axis, and is fitted into the circular hole at the upper end of the connecting rod 43 of the leveler 4. A circular hole is passed through the lower end of the connecting rod 43, and this circular hole is connected to a circular hole penetrated through the upper end of the forked fork end 44 by inserting a common pin 45 therethrough. The fork end 44 is held between two brackets 46, 46 and a roller 49 equipped with a shock-resistant bearing attached to the brackets. The brackets 46, 46 themselves are fixed to the frame 9 of the device. The other end of the fork end 44 has a male thread carved into it, and the turnbuckle 4
Screw together with the upper part of the female thread of No.2. Turnbuckle 42
At the bottom of the female thread is a mounting rod 4 which is screwed into the other end of the fork end 44 with a male thread carved in the opposite direction.
7 are connected, and by adjusting this screw, the height of the mounting rod 47 can be raised or lowered. A leveling body 41 is attached to the tip of the attachment rod 47 via an attachment plate 48. In this way, the leveling device 4 moves the fork end 44, which suspends the horizontally long leveling body 41 and makes intense vertical movements, to the belt conveyor 2.
Separate the center lines and equip two symmetrically. The driving force for the leveler 5 is also the chain 61.
It is transmitted to the chain wheel 62b via b, and the mechanism is similar to that of the leveler 4, but as described above, the stroke of the vertical movement of the leveler 51 is shortened by adjustment within the turnbuckle 52. . A stop plate 7 is disposed along the leveler 5, connected to an air cylinder 72 via a spring buffer 71 on the upper part, and further attached to the frame 9 of the device. Since this invention takes the above-mentioned technical measures, the mortar strip having the same width and thickness is transferred as it is to the recess of the flat formwork without excess or deficiency, and the two-dimensionally oriented fibers are transferred as they are. The effect of maintaining order and giving direction to products is remarkable. Table 1 shown below shows the physical property values (fracture strength MORKg/cm ² ) of premix glass fiber reinforced cement. In the table, Examples are after the premix mortar according to the present invention was transferred to a flat formwork.
After 28 days, a test piece was cut out in the direction of the flat plate. Comparative Example 1 shows numerical values for forming a plate using ordinary premix mortar, based on materials published by the Product Science Research Institute of the Ministry of International Trade and Industry. Comparative Example 2 is based on the values published in Japanese Patent Application Laid-Open No. 105303/1983, which is a prior art document that is the basis of the present invention.

[Table] As is clear from the table, the physical properties of the plate-shaped body according to the present invention are 20 to 30% higher than those of the conventional premix method, and even compared to those of the prior art which corrected the drawbacks. Improvements in physical properties (specifically, improvements in bending strength) have been observed, which has the effect of greatly expanding the range of applications of this material. As shown in the examples, the present invention is a manufacturing method limited to the purpose of mass producing smooth flat plates of the same size with few surface irregularities by forced forming action after premixing, and the most suitable apparatus for this method. It is. Furthermore, since this invention enables centralized management by chronologically arranging the driving relationships of the operation, basically unmanned operation is possible when producing large quantities of products of the same shape, which helps to streamline production in this industry and reduce costs. can make a significant contribution to reducing

[Brief explanation of drawings]

Fig. 1 is a front sectional view of the device to explain the concept of this invention, Fig. 2 is a front view of the same, Figs. 3 A, B,
C is a perspective sectional view illustrating how premix mortar is transferred from the device to the flat form;
FIG. 5 is a front view and a side view showing in detail the area around the leveler of the device of the present invention. 1... Mortar container, 2... Belt conveyor,
3... Shielding plate, 4... Leveler, 5... Leveler, 6... Drive motor, 7... Stop plate,
8...Flat formwork, 9...Device frame, 25...
Guide plate, 81...all partition plates, 82...rear partition plate, 83...recess.

Claims (1)

[Scope of Claims] 1. Mortar in which cement, sand, water, and reinforcing fibers such as glass fibers are mixed in advance is placed in a mortar container with a notch in the bottom, and placed on a belt conveyor communicating with the notch. The mortar is discharged out of the container in fixed quantities and subjected to high-speed beating action twice with different strokes to form a mortar band having an equal width and thickness, which is aligned with the guide plate at the tip of the belt conveyor. At the same time, the tip of the strip is inserted into the inner edge of the front partition plate of the cement board formwork that has been placed at the same time. At the same time, all equipment including the belt conveyor is retreated in synchronization with the advancement of the strip, and the strip is placed on the belt conveyor. This method is characterized in that the strip is cut off at a length that matches the inner edge of the rear partition plate of the formwork, and the strip is just fitted into the recess partitioned by the formwork partition plate using reinforced cement fiber premix mortar. A method for manufacturing shaku fiber reinforced cement board. 2. A mortar container with a notch at the bottom and a notch for discharging mortar at the lower end of one side continuous to the notch, and a mortar container connected to the notch at the bottom so as to be opened. A belt conveyor, a cutting adjustment plate for cutting out a certain amount of mortar,
The mortar container, the belt conveyor, the cut-out adjustment plate, the leveler, and A reinforcing fiber premix mortar supply device characterized in that a shielding plate is integrally assembled and the entire device is hung on a traveling frame so that it can be driven forward, backward, left and right.