Concrete mixer and concrete manufacturing method

Abstract

To provide a concrete mixer and a concrete manufacturing method which are safe and have excellent work efficiency.SOLUTION: A concrete mixer of the present invention is equipped with an injector that injects liquid as high-pressure water. The injector has a liquid flow path and a high-pressure injection nozzle, and when a mixing process of a previous batch of concrete is completed, high-pressure water is injected from the high-pressure injection nozzle so that it hits at least an agitator, and a measured material for a next batch is poured into a production tank in which the material peeled off from the agitator by the high-pressure water remains, and high-pressure water used for the peeling off, the material peeled off by the high-pressure water, and the measured material for the next batch that have been poured in are mixed in the agitator to produce the next batch of concrete. A concrete manufacturing method of the present invention is a method in which high-pressure water and the material peeled off by the high-pressure water are utilized in the manufacture of the next batch of concrete.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a concrete mixer and a concrete manufacturing method.

Background Art

[0002] In the concrete industry, hollow blocks and flooring blocks, which are representative in the field of immediate demolding, have recently shifted greatly from structural materials to landscape materials. These landscape materials have elements such as their design, texture, and color tone that greatly influence their commercial value, and most of them are mainly produced in small quantities of multiple varieties.

[0003] Under such circumstances, how to produce efficiently has become an urgent issue for manufacturers, and elimination of "waste time" that does not directly contribute to production, such as cleaning of machines, especially internal cleaning of concrete mixers, is required.

[0004] Conventionally, a concrete mixer has been used for manufacturing concrete. The concrete mixer includes a production tank and a stirrer that kneads (agitates) the materials in the production tank, and is manufactured by kneading the materials in the production tank with the stirrer.

[0005] The manufactured concrete is discharged out of the production tank from a discharge port provided in the production tank. However, since the concrete materials adhere to and remain on the inner surface of the production tank, the stirrer, etc., it is necessary to remove this at the timing after the end of one batch, the timing of mold change, etc.

[0006] As methods of removal, there are: 1) a method of manually performing with a kelon bar, a jet chisel, an air nozzle, etc.; 2) a method of manually performing with high-pressure water from the outside with the mixer stopped; 3) a method of cleaning the inside entirely with a plurality of fixed high-pressure injection nozzles fixed inside the container; 4) a method of projecting a part of the aggregate used as a material from a paddle wheel to crush and remove the adhering mass (Patent Document 1), etc.

Prior Art Documents

Patent Documents

[0007] [Patent Document 1] Japanese Patent Publication No. Hei 06-000331 [Summary of the Invention] [Problems to be Solved by the Invention]

[0008] Performing direct manual cleaning as described in 1) and 2) above not only has a poor working environment and is dangerous, but also has limitations in manual work and is less efficient compared to using a cleaning device.

[0009] When the position of the high-pressure injection nozzle is fixed as described in 3) above, the injection range is limited, so the probability that the cleaning water hits the stirring arm or stirring blade is as low as about once per rotation, and the cleaning efficiency is extremely poor.

[0010] In these methods, since the cleaning efficiency is poor, it is necessary to extend the cleaning time. However, when the cleaning time is extended, the amount of cleaning water used increases, and the cleaning drainage volume also increases significantly. In addition, a treatment device for neutralizing strong alkalinity is also required, which imposes a large economic burden.

[0011] In the method of projecting a part of the aggregate used as a material from the impeller to crush and remove the adhered mass as described in 4) above, the parts may wear due to the impact of the aggregate, and the part life may be shortened. In addition, in the block using a material with fine composition, since the projected aggregate is fine and lacks momentum, the removal performance may be significantly reduced in some cases.

[0012] The present invention has been made in view of such circumstances, and the problem to be solved is to provide a concrete mixer and a concrete manufacturing method that are safer and have better working efficiency compared to the above-mentioned methods. [Means for Solving the Problems]

[0013] [Concrete Mixer] The concrete mixer of the present invention is a concrete mixer equipped with a production tank into which materials are charged and a stirrer for stirring the materials in the production tank, and is equipped with an injector for injecting a liquid as high-pressure water. The injector is equipped with a liquid flow path and a high-pressure injection nozzle for injecting the liquid that has passed through the liquid flow path. In this concrete mixer, when the kneading process of the previous batch of concrete is completed, high-pressure water is injected from the high-pressure injection nozzle so as to cover at least the stirrer, and the measured materials for the next batch are charged into the production tank in which the materials peeled off from the stirrer by the high-pressure water remain. The next batch of concrete is manufactured by kneading the high-pressure water used for peeling, the materials peeled off by the high-pressure water, and the measured materials for the next batch that have been charged with a stirrer.

[0014] [Concrete manufacturing method] The concrete manufacturing method of the present invention is a method for manufacturing concrete using the concrete mixer of the present invention. After the kneading process of the previous batch of concrete is completed, high-pressure water is injected from the high-pressure injection nozzle so as to cover at least the stirrer, and the measured materials for the next batch are charged into the production tank in which the materials peeled off from the stirrer by the high-pressure water remain. The next batch of concrete is manufactured by kneading the high-pressure water used for peeling, the materials peeled off by the high-pressure water, and the measured materials for the next batch that have been charged with a stirrer. [Advantages of the Invention]

[0015] According to the present invention, it is possible to provide a concrete mixer and a concrete manufacturing method that are safer and have a lower environmental impact compared to the prior art. [Brief Description of the Drawings]

[0016]

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Mode for Carrying Out the Invention

[0017] (Embodiment 1) An example of an embodiment of the present invention will be described with reference to the drawings. As an example, the concrete mixer shown in FIG. 1 is a so-called vertical axis type concrete mixer, and includes a production tank 10, a drive motor M, a rotor 20, a stirrer 30, a scraping machine 40, and an injector 50 (FIG. 2).

[0018] The production tank 10 is a container for storing concrete materials (cement, water, aggregates, etc.). A predetermined amount of materials is automatically fed into the production tank 10 from a measuring device for measuring the materials in a timely manner.

[0019] The production tank 10 of this embodiment is a bottomed cylindrical shape with an open top, and a floor surface 11 is provided on the lower end side. The floor surface 11 is provided with a discharge port 12 for discharging the produced concrete outside the production tank 10. The discharge port 12 can be opened and closed by a movable opening and closing lid 13.

[0020] A plurality of supports 15 are attached to the peripheral edge portion 14 of the opening at the upper end of the production tank 10. Although not shown, a cover material that forms a part of the lid of the production tank 10 is attached to the support 15.

[0021] Above the support 15, a motor base 16 is supported. Two drive motors M are mounted on the motor base 16 as drive sources for rotating the rotor 20. In this embodiment, existing motors with speed reducers are used as the drive motors M.

[0022] As shown in FIG. 2, inside the motor base 16, pinions (hereinafter referred to as "motor pinions") 16a connected to the output shafts of the drive motors M are accommodated. Inside both motor pinions 16a, a rotor gear 16b that meshes with both motor pinions 16a is provided. When both motor pinions 16a are rotated by both drive motors M, the rotor gear 16b rotates accordingly.

[0023] A cylindrical rotor spindle 16c is provided at the center of the motor base 16. The rotor 20 is fixed to the rotor spindle 16c. When the motor pinions 16a and the rotor gear 16b rotate by the power of the drive motors M, the rotor spindle 16c and the rotor 20 fixed to the rotor spindle 16c rotate (revolve) accordingly.

[0024] An upper plate 16d is arranged on the upper end side of the rotor spindle 16, and a lower plate 16e is arranged on the lower end side. The rotor spindle 16 is fixed and held by the upper plate 16d and the lower plate 16e.

[0025] As shown in FIG. 3, the rotor 20 of this embodiment is rhombic in plan view. Inside the rotor 20, a planetary gear 21 (FIG. 5) for rotating the stirrer 30 is provided. The rotor 20 is provided with a stirrer 30 for stirring the material in the production tank 10 and a scraping machine 40 for scraping off the concrete adhering to the inner peripheral surface of the production tank 10.

[0026] As shown in FIGS. 3 and 4, one stirrer 30 (two in total) is provided at positions near both ends in the longitudinal direction on the back side of the rotor 20, and one scraping machine 40 (two in total) is provided on the side surfaces at both ends in the short direction of the rotor 20.

[0027] As shown in FIG. 5, the stirrer 30 includes a casing 31, and a rotating body 33 is provided inside the casing 31 via a bearing 32. The rotating body 33 is adapted to rotate (revolve) by a planetary gear 21 provided in the rotor 20. Approximately the lower half of the rotating body 33 protrudes below the lower end of the casing 31, and an arm base 34 that rotates together with the rotating body 33 is provided on the protruding portion.

[0028] The arm base 34 is provided in a direction orthogonal to the rotating body 33, and stirring arms 35 are provided at portions protruding from both outer sides of the rotating body 33. Stirring blades 36 are attached to the tips of the respective stirring arms 35, and the materials in the production tank 10 are stirred by the stirring arms 35 and the stirring blades 36.

[0029] Cylindrical chambers 37 (FIG. 8) are provided at positions of the respective stirring arms 35 near the arm base 34 so as to cover a through passage 51f described later. High-pressure injection nozzles 52 for injecting a liquid (water) used for cleaning at high pressure are provided in the respective cylindrical chambers 37.

[0030] The scraping machine 40 includes a scraper arm 41, and a vertically long side scraper 42 is provided at the tip thereof. The side scraper 42 is provided so as to be applied to the inner peripheral surface of the production tank 10.

[0031] The injector 50 is a device that injects a liquid as high-pressure water. As the liquid to be injected, water, more specifically, water used as a material for concrete can be used.

[0032] The injector 50 of this embodiment includes a liquid flow path 51 and a high-pressure injection nozzle 52. As shown in FIGS. 5 to 8, the liquid flow path 51 includes a vertical supply pipe 51a provided inside the rotor main shaft 16c, a first branch path 51b provided on the lower end side of the vertical supply pipe 51a, an internal supply path 51c provided inside the rotating body 33, a second branch path 51d provided on the lower end side of the rotating body 33, an internal passage 51e provided longitudinally along the center of the stirring arm 35, a through passage 51f communicating from the internal passage 51e to the outside of the stirring arm 35, and a discharge path 51g provided in the cylindrical chamber 37 so as to communicate from the through passage 51f to the high-pressure injection nozzle 52.

[0033] The vertical supply pipe 51a, the first branch path 51b, the internal supply path 51c, the second branch path 51d, the internal passage 51e, the through passage 51f, and the discharge path 51g are connected in this order via a joint member J and function as a series of liquid flow paths 51 through which the liquid passes.

[0034] On the upstream side of the liquid flow path 51, a high-pressure water distribution device for supplying liquid to the liquid flow path 51 is connected via a high-pressure water connection pipe 53 installed at the center of the upper plate 16d.

[0035] Note that rotary water-tight seals 54a and 54b for preventing water leakage are provided at the connection points between the vertical supply pipe 51a and the high-pressure water connection pipe 53 and between the first branch path 51b and the internal supply path 51c. Existing or new rotary water-tight seals 54a and 54b can be used.

[0036] On the downstream side of the liquid flow path 51, a high-pressure injection nozzle 52 is connected. The high-pressure injection nozzle 52 injects the liquid that has passed through the liquid flow path 51 as high-pressure water. The high-pressure injection nozzle 52 is provided on the outer periphery of each stirring arm 35.

[0037] A plurality of high-pressure injection nozzles 52 are provided at positions near the upper ends of the stirring arms 35. Each high-pressure injection nozzle 52 is preferably provided such that high-pressure water is injected at least into the stirrer 30 (specifically, the stirring arm 35 and the stirring blade 36), and more preferably, high-pressure water is injected into the stirrer 30 and the scraping machine 40 (specifically, the side scraper 42). The front direction of the injection direction is provided so as to face the stirring arm 35, the stirring blade 36, and the side scraper 42.

[0038] (Embodiment 2) Another example of an embodiment of the present invention will be described with reference to the drawings. The basic structure of the concrete mixer of this embodiment is the same as that of the concrete mixer of Embodiment 1. The differences are the structures of the stirring arm 35 and the stirring blade 36, and the installation angle (injection angle) of the high-pressure injection nozzle 52.

[0039] As shown in FIG. 9, the stirring arm 35 and the stirring blade 36 of this embodiment are configured as an integral body. The stirring arm 35 is flat and includes an upper arm portion 35b above the bent portion 35a and a forearm portion 35c below the bent portion 35a. A stirring blade 36 is provided on the lower end side of the forearm portion 35c.

[0040] As shown in FIG. 10, the upper arm portion 35b projects in a direction perpendicular or substantially perpendicular to the arm base 34 when viewed from the plane, and the forearm portion 35c is provided so as to be refracted in an inward direction when viewed from the plane.

[0041] Specifically, as shown by the broken line in FIG. 10, when the stirring blade 36 approaches the inner peripheral surface of the production tank 10, the outer side 35d of the forearm portion 35c is parallel or substantially parallel to the stirring direction. In other words, it is arranged along the flow direction of the material during stirring (the direction indicated by the dashed-dotted arrow in FIG. 10).

[0042] The front arm portion 35c of the stirring arm 35 is the part where the material is most likely to adhere. However, by setting the angle of the outer side 35d of the front arm portion 35c to an angle along the flow direction of the material, the timing for the material to flow along the moving direction of the outer side 35d can be achieved. At that timing, the material near the front arm portion 35c flows along the outer side 35d, making it difficult for the material to stay near the front arm portion 35c and less likely for the material to adhere to the front arm portion 35c.

[0043] Such an effect can also be achieved when the stirring arm 35 is in the shape of a round bar. However, when the stirring arm 35 is in the shape of a flat plate as in Embodiment 2 and the contact area with the material is reduced, this effect appears as a significant difference. When the stirring arm 35 has a shape without irregularities, this effect becomes even more significant.

[0044] When the front arm portion 35c of the stirring arm 35 is set at such an angle, during stirring, the material will be washed away by the material itself, preventing the material from adhering to the front arm portion 35c by the material. In other words, a self-cleaning effect works, and almost no material adheres to the front arm portion 35c.

[0045] When using the stirring arm 35 of Embodiment 2, since the amount of material adhering to the front arm portion 35c can be minimized, it is not necessary to inject high-pressure water from the high-pressure injection nozzle 52 to the front arm portion 35c. On the other hand, fine splashes of high-pressure water adhere to the upper arm portion 35b, and fine particles of aggregate and cement powder scattered in the production tank 10 may adhere to these splashes. Therefore, cleaning with high-pressure water is required.

[0046] For this reason, as shown in FIG. 11, the high-pressure injection nozzle 52 of this embodiment is installed facing the upper arm portion 35b so that high-pressure water can be injected into the upper arm portion 35b. The upper arm portion 35b is not a part that comes into contact with the material during stirring and has a small amount of material adhering to it. Therefore, the amount of water used for cleaning can be minimized, and the cleaning time can be shortened.

[0047] In recent years, the demand for multi-color concrete blocks obtained by mixing multiple colors has been on an increasing trend. However, when manufacturing multi-color concrete blocks, the amount of concrete kneaded at one time is only about one-half or one-third of that in the case of a single color, and the adjustment of the amount of mixing water becomes stricter accordingly. Depending on the moisture condition of the aggregate and the material composition, there may be cases where no mixing water is added.

[0048] When kneading such a small amount of concrete, if the amount of water is too large, it becomes impossible to produce concrete with an appropriate viscosity. Therefore, it is necessary to minimize the amount of high-pressure water used for cleaning.

[0049] In this regard, according to the concrete mixer of Embodiment 2, as long as there is an amount of water for removing the material adhering to the upper arm portion 35b, the amount of high-pressure water used for cleaning can be minimized. Therefore, it can be suitably used even when producing a small amount of concrete such as multi-color concrete blocks.

[0050] Further, in the case of the concrete mixer of Embodiment 2, since the amount of high-pressure water used is small, the amount of water particles scattered in the production tank 10 also decreases, and it is possible to suppress adhesion to the inner wall of the production tank 10, the periphery of the discharge port 12, and the surface of the casing.

[0051] As a result, adhesion of fine particles of aggregate and cement powder to these locations is also suppressed, and the labor for cleaning can be reduced. Further, by suppressing the adhesion of fine particles of aggregate and cement powder around the discharge port 12, it is possible to prevent events such as the opening / closing lid 13 not closing due to material adhesion, and water entering from the gap of the opening / closing lid 13 that did not fully close and dripping onto the lower chute, which promotes material adhesion.

[0052] The configurations of the above two embodiments are examples, and the concrete mixer of the present invention is not limited to the above configurations. The concrete mixer of the present invention can be appropriately modified by adding, omitting, or replacing components within the range that can achieve the intended purpose.

[0053] (Operation) Next, the operation of the concrete mixer of Embodiment 1 (the method for cleaning the concrete mixer and the method for manufacturing concrete) will be described. Here, an example is a case where concrete is repeatedly manufactured by a batch method. For convenience of explanation, the batch performed first is referred to as the previous batch, and the batch following it is referred to as the next batch. Note that the previous batch and the next batch are relative concepts. For example, the second batch is the next batch in relation to the first batch, and is the previous batch in relation to the third batch.

[0054] (1) The aggregate, cement, and water measured by the measuring device are put into the production tank 10 in this order from the measuring device. (2) When the materials (aggregate, cement, and water) are put in, the materials are stirred (kneaded) by the stirrer 30, and the kneading process for the previous batch is completed, and the concrete is completed. (3) When the kneading process is completed and the concrete for the previous batch is completed, the opening / closing lid 13 on the floor surface 11 of the production tank 10 opens, and the concrete is discharged out of the production tank 10. (4) When the concrete for the previous batch is discharged, the opening / closing lid 13 is closed, and high-pressure water is sprayed from the high-pressure spray nozzle 52 of the injector 50. The high-pressure water is sprayed toward the stirrer 30 and the scraping machine 40 (specifically, the stirring arm 35, the stirring blade 36, and the side scraper 42), and the materials (hereinafter referred to as "adhered materials") adhering to these are peeled off. (5) When the adhered materials are peeled off by the high-pressure water, the measured materials for the next batch are supplied (put) into the production tank 10. The measured materials for the next batch are put into the production tank 10 in the order of aggregate, cement, and water. (6) When the measured materials are put into the production tank 10, the high-pressure water used for peeling, the adhered materials peeled off by the high-pressure water, and the materials for the next batch put in are stirred (kneaded) by the stirrer 30, and the kneading process for the next batch is completed, and the production of concrete is completed. Thereafter, the steps (3) to (6) are repeated for each batch.

[0055] In addition, in the above (5), the pre-measured materials for the next batch are preset in consideration of the amount of water used for peeling the adhered materials in the above (4). For example, when 100 L of water is required to produce one batch of concrete, and 20 L of water is introduced for cleaning after the previous batch, then the remaining 80 L will be introduced.

[0056] Thus, in the concrete mixer of Embodiment 1, high-pressure water is sprayed from the high-pressure injection nozzle 52 while trailing the rotating stirring arm 35, stirring blade 36, and side scraper 42, and the high-pressure water can be directly sprayed onto these members where the most material adheres. Therefore, the adhered material can be efficiently removed. As a result, the adhered material can be peeled (cleaned) in a short time, and furthermore, the amount of water used for peeling the adhered material can be significantly reduced.

[0057] Also, in the concrete mixer of Embodiment 1, since the water used for cleaning and the peeled (removed) adhered materials are directly used as part of the materials for the next batch, the discharge amount of the cleaning liquid can be made zero, which is friendly to the global environment.

[0058] In addition, in the method of using aggregate, which is one of the conventional methods, to peel the adhered material, the peeling effect depends on the size of the aggregate particle size. When the particle size is small, the adhered material may not be completely removed. On the contrary, in the method of using high-pressure water with good directivity like the concrete mixer of Embodiment 1, there is no such risk. If the mounting position and mounting direction of the high-pressure injection nozzle 52 are accurately adjusted, the adhered material can be surely removed.

[0059] Also, in Embodiment 1, since high-pressure water without aggregate is used for peeling the adhered material, the risk of abrasion of the stirring arm 35, stirring blade 36, and side scraper 42 is low (at least there is no abrasion like the case of colliding with aggregate), and the problem of contamination due to abrasion of the stirring arm 35, stirring blade 36, and side scraper 42 is less likely to occur.

[0060] Here, the operation of the concrete mixer according to the first embodiment has been described as an example, but the operation of the concrete mixer according to the second embodiment is the same.

Industrial Applicability

[0061] The concrete mixer and the concrete manufacturing method of the present invention can be suitably used, for example, as an apparatus and a method used when manufacturing concrete in a batch system.

Explanation of Signs

[0062] 10 Generation tank 11 Floor surface 12 Discharge port 13 Opening / closing lid 14 Peripheral edge of opening 15 Support 16 Motor base 16a Pinion (motor pinion) 16b Rotor gear 16c Rotor main shaft 16d Upper plate 16e Lower plate 20 Rotor 21 Planet gear 30 Agitator 31 Casing 32 Bearing 33 Rotating shaft 34 Arm base 35 Stirring arm 35a Bending part 35b Upper arm part 35c Forearm part 35d Outer side 36 Stirring blade 37 Cylindrical chamber 40 Scraping machine 41 Scraper arm 42 Side scraper 50 Injector 51 Liquid flow path 51a Vertical supply pipe 51b First branch path 51c Internal supply path 51d Second branch path 51e Inner passage 51f Through passage 51g Discharge path 52 High-pressure injection nozzle 53 High-pressure water connection pipe 54a, 54b Rotary watertight seal J Joint member M Drive motor

Claims

1. A concrete mixer having a generating tank into which materials are fed and an agitator for agitating the materials in the generating tank, Equipped with an injector that injects liquid as high-pressure water, The injector includes a liquid flow path and a high-pressure injection nozzle for injecting the liquid that has passed through the liquid flow path, When the mixing process of the previous batch of concrete is completed, high-pressure water is sprayed from the high-pressure spray nozzle so as to hit at least the agitator, The measured amount of material for the next batch is added to the production tank in which the material removed from the mixer by the high-pressure water remains, The high-pressure water used for the stripping, the material stripped by the high-pressure water, and the weighed material for the next batch that has been added are mixed in the mixer to produce the next batch of concrete. A concrete mixer characterized by:

2. In the method for producing concrete using the concrete mixer according to claim 1, After the mixing process for the previous batch of concrete is completed, high-pressure water is sprayed from the high-pressure spray nozzle so that it hits at least the agitator, A weighed amount of material for the next batch is poured into the production tank in which the material peeled off from the mixer by the high-pressure water remains, The high-pressure water used for the stripping, the material stripped by the high-pressure water, and the weighed material for the next batch that has been added are mixed with the mixer to produce the next batch of concrete. A method for producing concrete comprising the steps of:

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