JP2010082921A - Concrete mixer, method for washing concrete mixer, and method for producing ready-mixed concrete - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a concrete mixer which can efficiently carry out the washing mortar in concrete adherent to arm parts and blades which are difficult to be washed, without causing abrasion by friction and collision between metal parts. <P>SOLUTION: The compulsive horizontal two-shaft type concrete mixer A includes a kneading vessel 11, a pair of mixer shafts 12 which can rotate around a horizontal shaft in the mixing vessel 11, an arm part 13 suitable for each mixer shaft 12, and the blade 14 attached to each arm part 13. In the concrete mixer A, a mixer shaft side conduit run 121 and an arm part side conduit run 131 are installed in the mixer shaft 12 and the arm part 13, respectively, and a spray means 3 is provided, which sprays high-pressure water or compressed air which contributes to washing or the mixture of them toward arm part 13 and the blades 14 using the mixer shaft side conduit run 121 and the arm part side conduit run 131. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a concrete mixer, a concrete mixer cleaning method, and a ready-mixed concrete manufacturing method.

  In general, ready-mixed concrete (in addition to narrow-ready ready-made concrete, is a concept that includes mortar and cement composition that does not contain coarse aggregates; hereinafter referred to as “ready concrete” or “ready-mixed”) is manufactured at a ready-mixed factory. Then, it is transported and delivered to the site with a truck agitator. Most of the ready-mixed factories are JIS (Japanese Industrial Standards) -certified factories and use concrete mixers that meet JIS regulations (JIS A 8603 concrete mixers).

  The mortar content in the concrete adhering to the concrete mixer through the mixing process (in the narrow sense, the mortar content is cement, fine aggregate, water, admixture, excluding the coarse aggregate in the raw concrete composition. It represents a mortar part mixed with wood and admixture, but some coarse aggregate is actually mixed.) Is usually washed with high-pressure water after shipment of mixed concrete. However, washing with high-pressure water or the like is often insufficient, and the mortar content in concrete is regularly picked up manually.

  Therefore, in order to eliminate the work of manually removing the mortar content in the concrete adhering to the concrete mixer, high pressure water is sprayed from above the kneading tank to the side wall, the mixer shaft, and the arm portion of the kneading tank (hereinafter referred to as “first” For example, refer to Patent Document 1), or a special metal ring is attached to the mixer shaft, and the mixer shaft is rotated to remove the mortar content in the concrete adhered by the friction of the metal ring ( Hereinafter, it is referred to as “second well-known aspect.” For example, see Patent Document 2).

By the way, the concrete mixer is usually washed at the end of shipment and when there is a large interval (for example, 1 hour or more) in the shipment time. This is because few factories have facilities that send wastewater containing aggregates directly to wastewater treatment facilities, and many factories transport them to wastewater treatment facilities with truck agitators. If the concrete mixer is washed frequently, the amount of wastewater treatment associated with it will increase, the equipment will need to be operated for a long time, and the amount of industrial waste will also increase. The reason is that it is not preferable to wash the concrete mixer more than necessary because it prevents the ready-mixed concrete from adhering to the concrete mixer by attaching an appropriate amount of mortar to the concrete mixer in advance. A point is mentioned.
JP-A-8-192420 Japanese Patent No. 3432789

  However, it is extremely difficult to attach only an appropriate amount of mortar to the concrete mixer each time, and when the amount of adhesion is extremely reduced, the mortar hardens quickly and is difficult to clean.

  Usually, the mortar adheres excessively in the vicinity of the arm portion and blades of the concrete mixer, which are also difficult to clean. In the first well-known aspect, since the injection position of the high-pressure washing water is above the kneading tank, there is a problem that the water pressure is lowered far from the arm portion and the blades and sufficient washing cannot be performed. Further, in the second well-known aspect, since a metal ring is used, there is a problem of friction between metals and wear due to collision.

  The present invention has been made paying attention to such problems. The main purpose of the present invention is to clean the mortar in the concrete adhering to the arm portion and the blade, which are difficult to clean, by friction between metals. Another object of the present invention is to provide a concrete mixer, a method for cleaning a concrete mixer, and a method for producing ready-mixed concrete that can be efficiently performed without causing wear due to a collision.

  That is, the concrete mixer of the present invention is a compulsory for producing ready-mixed concrete comprising a pair of mixer shafts that can rotate around a horizontal axis, arm portions provided on each mixer shaft, and blades provided on each arm portion. Type horizontal biaxial concrete mixer, wherein at least the mixer shaft and the arm portion are provided with pipes, and by using these pipes, a liquid or air that contributes to cleaning, or a mixture thereof It has a spraying means for spraying toward the arm part and the blade.

  Here, “contributing to cleaning” is a concept including both of “contributing directly to cleaning or indirectly contributing to cleaning”. Examples of the “liquid that contributes to cleaning” include water, an admixture that is a raw concrete material, or a dedicated cleaning agent.

  If this is the case, a single unit of liquid or air that contributes to cleaning, or a mixture thereof, by means of spraying using a pipe provided in the mixer shaft or arm portion disposed in the kneading tank Is sprayed toward the arm part and the blades, and the spray position (injection position) is set in the kneading tank, which is a problem that occurs when the injection position is above the kneading tank, that is, far from the arm part and the blades. The problem that the water pressure is lowered and sufficient cleaning cannot be performed is solved, and the cleaning of the mortar in the concrete attached to the arm and blades, which are difficult to clean, can be performed efficiently. Moreover, since the spraying means sprays a liquid or air alone or a mixture thereof that contributes to cleaning toward the arm part and the blades, it does not cause wear due to friction or collision between metals, and is highly practical. It will be a thing.

  In particular, if the pipes provided inside the mixer shaft and the arm part have a plurality of outlets that open toward the arm part or the blades, the outlets contribute to cleaning. The liquid or air alone or a mixture thereof can be sprayed from a short distance toward the arm portion and the blades, and cleaning can be performed more effectively. Moreover, the discharge port itself can be easily formed by drilling the mixer shaft and the arm portion.

  In addition, if the spraying means uses a liquid and compressed air that contributes to cleaning, or a pressure vessel that contains only compressed air, high-pressure liquid or compressed air is sprayed toward the arm portion or blade. It is possible to easily adjust the discharge pressure of high-pressure liquid and compressed air by adjusting the pressure inside the pressure vessel as appropriate. And by adjusting the discharge pressure of compressed air, the amount of mortar attached can be cleaned to an appropriate amount, leading to a reduction in cleaning time.

  Here, the term “mortar” means, in a narrow sense, a mortar part in which cement, fine aggregate, water, an admixture, and an admixture are kneaded, excluding the coarse aggregate in the ready-mixed concrete composition. Partly contains coarse aggregate. And in this application, what can partially contain coarse aggregate is described as mortar or simply mortar.

  Here, “attachment of mortar” is a concept including adhesion of mortar in concrete and concrete in addition to adhesion of mortar in concrete.

  The concrete mixer cleaning method of the present invention is a method for cleaning the above-described concrete mixer, and contributes to cleaning by the spraying means when discharging the ready-mixed concrete kneaded at least in the kneading tank to the outside of the kneading tank. Air is blown onto the arm part and the blade.

  Conventionally, the mortar adhered to the arm part and blades could not be cleaned for each batch discharge, but if the concrete mixer cleaning method of the present invention was used, the ready-mixed concrete that had been kneaded in the kneading tank was removed from the kneading tank. When each batch is discharged, air can be blown to the arm and blades to blow away the mortar in the concrete adhering to the arms and blades. Since the mortar part already attached to the arm portion and the blades is blown to some extent, the cleaning operation can be easily performed, which contributes to shortening of the cleaning time. Here, “the air blown to the arm part and the blade” itself blows away the mortar content in the concrete adhering to the arm part and the blade, and does not wash off, so it does not directly contribute to washing. It contributes to the reduction of the cleaning work performed after the completion of all batches, and can be said to be “indirectly contributing to cleaning”. Moreover, since it is an aspect which blows away the mortar part adhering to an arm part and a blade | wing by blowing air, the increase in wastewater treatment amount was suppressed and the long time operation of the equipment accompanying the increase in wastewater treatment amount was required Can solve the conventional problems.

  The concrete mixer cleaning method of the present invention is a method for cleaning the above-described concrete mixer, wherein after the mixing, the spraying means sprays a liquid that contributes to cleaning onto the arm portion and the blades.

  If it is such a washing | cleaning method, the mortar part adhering to the arm part and blade | wing which are difficult to wash | clean can be efficiently washed away by spraying a liquid on an arm part and a blade | wing after kneading. Here, the “liquid sprayed to the arm part and the blade” is for washing away the mortar in the concrete adhering to the arm part and the blade, and can be said to be “a direct contribution to the cleaning”.

  Moreover, the method for producing ready-mixed concrete of the present invention is a method for manufacturing ready-mixed concrete using the above-described concrete mixer, and at least when the ready-mixed concrete kneaded in the kneading tank is discharged out of the kneading tank, Air that contributes to cleaning is blown onto the arm portion and the blade.

  With such a method for producing ready-mixed concrete, when the ready-mixed concrete that has been kneaded in the kneading tank is discharged out of the kneading tank, that is, for each batch discharged, by blowing air that contributes to cleaning to the arm portion and the blades. The mortar attached to the arm and blades, which are difficult to clean for each batch, can be blown to some extent, which contributes to a reduction in the work load during cleaning.

  As described above, according to the present invention, it is possible to efficiently clean the mortar in the concrete adhering to the arm portion and the blade, which is difficult to clean, without causing friction between metals and wear due to collision. It is possible to provide a concrete mixer, a method for cleaning a concrete mixer, and a method for producing ready-mixed concrete.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the concrete mixer A according to the present embodiment includes a tank (water tank B1, admixture tank B2, aggregate tank tank B3), storage bin (water storage bin C1, admixture storage bin C2, The batching plant X is configured together with an aggregate storage bin group C3), a metering device (water metering device D1, admixture metering device D2, aggregate metering device group D3) and the like.

  The concrete mixer A is a forced horizontal biaxial type mainly composed of the mixer body 1.

  As shown in FIGS. 1 and 2, the mixer body 1 includes a kneading tank 11 that opens upward, a pair of mixer shafts 12 that can rotate around the horizontal axis in the kneading tank 11, and a substantially radial shape on each mixer shaft 12. And the blades 14 provided at the tip of each arm 13.

  The kneading tank 11 includes a front wall portion 111 and a rear wall portion 112 facing each other, a pair of side wall portions 113, and a bottom wall portion 114, and a discharge for discharging the mixed concrete mixed into the bottom wall portion 114. A gate (not shown) is provided. The point which comprises the raw concrete material kneaded from the upper part of this kneading tank 11 is the same as the conventional thing.

  The mixer shafts 12 are provided in parallel with each other between the side wall portions 113 of the kneading tank 11 and are rotatably supported by the mixer bearings 16. In FIG. 2, only a single mixer shaft 12 is shown in the drawing. Each mixer shaft 12 is driven by a motor 15 disposed outside the kneading tank 11 and is set to rotate in directions opposite to each other. Each mixer shaft 12 forms therein a pipe line (hereinafter referred to as “mixer shaft side pipe 121”) along the axial direction. The mixer shaft side pipe line 121 has a single inlet opening that opens to one end side of the mixer shaft 12 and a plurality of discharge ports that are provided at a predetermined pitch along the axial direction of the mixer shaft 12 and open into the kneading tank 11. (Hereinafter referred to as “mixer shaft side discharge port 121a”). By setting the opening direction of each mixer shaft side discharge port 121a regularly or irregularly in a direction orthogonal or substantially orthogonal to the axial direction of the mixer shaft 12, each mixer shaft side discharge port 121a is suitable for people. One end of the mixer shaft 12 is connected to a single rotary joint 54 described later, and the other end is connected to the motor 15.

  Each arm portion 13 is provided at a predetermined pitch along the axial direction of the mixer shaft 12, and is arranged in a posture in which the axial direction (projection direction) is orthogonal or substantially orthogonal to the axial direction of the mixer shaft 12. Each arm part 13 forms a pipe line (hereinafter referred to as “arm part side pipe line 131”) along the axial direction. The arm part side conduit 131 is provided at a predetermined pitch along the axial direction (protruding direction) of the arm part 13 with a single inlet opening that opens to the base end part side of the arm part 13, and opens into the kneading tank 11. And a plurality of discharge ports (hereinafter referred to as “arm portion side discharge ports 131a”). By connecting the base end portion of the arm portion 13 to a portion of the mixer shaft 12 provided with the mixer shaft side discharge port 121a in which the opening direction is set in a direction orthogonal to the axial direction of the mixer shaft side conduit 121. The arm part side pipe line 131 and the mixer shaft side pipe line 121 are communicated with each other via the mixer shaft side discharge port 121a. By setting the opening direction of each of the arm portion side discharge ports 131a regularly or irregularly in a direction orthogonal to or substantially orthogonal to the axial direction (protruding direction) of the arm portion 13, each arm The part-side discharge port 131a is adapted to people. As a result, among these arm portion side discharge ports 131 a, some of the arm portion side discharge ports 131 a open toward the blades 14 and other arm portions 13. Further, with the arm portion 13 attached to the mixer shaft 12, several mixer shaft side discharge ports 121 a are opened in the kneading tank 11, and the mixer shaft side discharge ports 121 a exposed in the kneading tank 11 are opened. Among them, some of the mixer shaft side discharge ports 121 a are open toward the arm portion 13 and the blades 14. 2 shows only the mixer shaft side discharge port 121a and the arm portion side discharge port 131a opened in the direction orthogonal to or substantially orthogonal to the axial direction of the mixer shaft 12 and the axial direction of the arm portion 13, respectively. . In the present embodiment, the opening diameters of the mixer shaft side discharge port 121a and the arm portion side discharge port 131a are set to, for example, several mm.

  Each blade 14 is provided at the tip of each arm portion 13 and exhibits a function of directly kneading various materials charged into the kneading tank 11 together with the arm portion 13. The shape and mounting direction of the blades 14 are not particularly limited.

  The mixer main body 1 used in the present embodiment is the same as the existing (known) mixer main body except that the mixer shaft side pipe 121 and the arm part side pipe 131 are provided.

  Thus, the concrete mixer A according to the present embodiment uses the mixer shaft side pipe line 121 and the arm part side pipe line 131, and water, an admixture, or compressed air that is a raw concrete material, or those Liquid that contributes to cleaning or compression using the internal injection means 2 for injecting any of the above mixture from the inside of the ready-mixed concrete, the mixer shaft side pipe 121 and the arm part side pipe 131 A spraying means 3 for spraying air alone or a mixture thereof toward the arm portion 13 and the blades 14 is provided.

  The internal injection means 2 includes a pressure vessel (a first pressure vessel 4a for material injection, a second pressure vessel 4b for material injection, a pressure vessel 4c exclusively for compressed air) and a pressure vessel (first pressure vessel 4a for material injection, material injection). The second pressure vessel for pressure 4b, the pressure vessel for compressed air 4c) and the mixer shaft 12, and the pressure vessel (the first pressure vessel for material injection 4a, the second for material injection) via the connection route 5. A pressure vessel 4b and a compressed air dedicated pressure vessel 4c) provided with a mixer shaft side pipe 121 and an arm part side pipe 131 for injecting the material (water, admixture, compressed air) into the kneading tank 11. Is.

  In this embodiment, the spraying means 3 is comprised using each member which comprises the internal injection means 2. As shown in FIG. That is, the internal injection means 2 and the spray means 3 are comprised by the substantially common member. When each member constituting the internal injection means 2 functions as the spray means 3 in cooperation, the pressure vessel (the first pressure vessel 4a for material injection, the second pressure vessel 4b for material injection, the pressure vessel 4c exclusively for compressed air) The water or compressed air inside acts as a contribution to cleaning. That is, in the present embodiment, “water” is applied as “liquid contributing to cleaning”, more specifically “high pressure water”, and “compressed air” is applied as “air contributing to cleaning”.

  Each pressure vessel (the first pressure vessel 4a for material injection, the second pressure vessel 4b for material injection, and the pressure vessel 4c exclusively for compressed air) is connected to the compressor 7 via the open / close valve 6, respectively. In this embodiment, a total of three pressure vessels are used, of which two pressure vessels (hereinafter referred to as “material injection first pressure vessel 4a” and “material injection second pressure vessel 4b”) are used. Water, an admixture, and compressed air are stored inside, and the remaining one pressure vessel (hereinafter referred to as “compressed air dedicated pressure vessel 4c”) stores only compressed air therein. Here, the compressed air dedicated pressure vessel 4c functions exclusively as a part of the blowing means 3. That is, among the three pressure vessels (the first pressure vessel 4a for material injection, the second pressure vessel 4b for material injection, and the pressure vessel 4c exclusively for compressed air), the pressure vessel constituting the internal injection means 2 is material injection. The first pressure vessel 4a for use and the second pressure vessel 4b for material injection. If the capacity of the existing compressor is sufficient, the compressor may be diverted as the compressor 7.

  The communication path 5 includes a pressure vessel side pipe 51 having an upstream end connected to the discharge port of each pressure vessel (the first pressure vessel 4a for material injection, the second pressure vessel 4b for material injection, and the pressure vessel 4c exclusively for compressed air). The downstream branch valve 52 connected to the downstream end of each pressure vessel side pipe 51, the main pipe 53 having the upstream end connected to the downstream branch valve 52, and the downstream end of the main pipe 53 A single rotary joint 54 is provided. In this embodiment, two single rotary joints 54 are used, and two main pipes 53 branched in the middle by branch pipes 53a (for example, cheese of a three-way RC female thread) are connected to the single rotary joints 54, respectively. is doing. The mixer shaft 12, which is a rotating body, and the fixed main pipe 53 are connected via a single rotary joint 54, and the main pipe 53 and the mixer shaft side pipe 121 are connected. One end of each mixer shaft 12 is threaded, and the mixer shaft 12 is attached to the single rotary joint 54 using threading. FIG. 2 shows a state in which one main pipe 53 is connected to one mixer shaft 12 via a single rotary joint 54 among main pipes 53 branched in the drawing. The main pipe 53 is also connected to the other mixer shaft 12 via a single rotary joint 54 (not shown).

  In addition, the concrete mixer A of the present embodiment performs excessive compression so that each pressure vessel (the first pressure vessel 4a for material injection, the second pressure vessel 4b for material injection, and the pressure vessel 4c exclusively for compressed air) has a normal pressure. An auxiliary pipe 8 for discharging air is provided between the downstream branch valve 52 of the communication path 5 and the mixer body 1. The auxiliary pipe 8 has an upstream end connected to the downstream branch valve 52, and the downstream end is positioned in the kneading tank 11 from the upper part of the kneading tank 11, for example, through the side wall 113. The compressed air is discharged into the kneading tank 11 from the discharge port. Note that the height of the auxiliary pipe 8 attached to the kneading tank 11 is set so that the outlet of the auxiliary pipe 8 is not buried in the ready-mixed concrete in the kneading tank 11. The downstream branch valve 52 connected to the main pipe 53 and the auxiliary pipe 8 includes a main pipe open state opened only to the main pipe 53, an auxiliary pipe 8 state opened only to the auxiliary pipe 8, a main pipe 53, and It can be switched between a closed state that is not open to any of the auxiliary pipes 8.

  As shown in FIG. 1, the batching plant X equipped with the concrete mixer A includes a tank (water tank B1, admixture tank B2, aggregate tank B3), and each tank (water tank B1, admixture tank B2, A storage bin (water storage bin C1, admixture storage bin C2, aggregate storage bin group C3) for storing materials provided from the aggregate tank group B3) and a weighing device capable of measuring each material separately. (Water metering device D1, admixture metering device D2, aggregate metering device group D3). As for water and admixture, water tank B1, water storage bottle C1, water metering device D1, admixture tank B2, admixture storage bin C2, and admixture metering device D2 may be mentioned. These are all existing products (note that an existing concrete mixer known from the past is shown in FIG. 3 in correspondence with FIG. 1). There are also dedicated tanks, storage bottles, and measuring devices for aggregates, cements, and admixtures (powder). Existing products are also applied to these, and Fig. 1 shows aggregates, cements, and admixtures. Reference numerals B3, C3, and D3 are assigned to the (powder) tank group, storage bin group, and weighing device group, respectively. Various materials are introduced from above the kneading tank 11 from each metering device (water metering device D1, admixture metering device D2, aggregate metering device group D3) through a discharge port such as a hopper (not shown). In addition, when these discharge outlets, such as a hopper, are considered as a part of concrete mixer A, the concrete mixer A which concerns on this embodiment is provided with the external injection | throwing-in means which throws in the raw concrete material from the upper direction of the kneading tank 11. On the other hand, if the discharge port of the hopper or the like is considered to be a part of the weighing device that is a separate device from the concrete mixer A, or independent from the concrete mixer A or the weighing device, the concrete according to the present embodiment It can be said that the mixer A kneads the raw concrete material charged from above the kneading tank 11 by external charging means mainly having a discharge port such as a hopper. Regardless of the interpretation, the point that the raw concrete material is charged from above the kneading tank 11 is the same.

  In this embodiment, the piping from the water storage bin C1 to the water metering device D1 and the piping from the admixture storage bin C2 to the admixture metering device D2 are branched by, for example, a three-way RC female screw cheese, etc. The water metering device D11 and the internal injection admixture metering device D21 are connected to each other. Furthermore, the internal injection water metering device side pipe D12 and the internal injection admixture metering device side pipe D22 connected to the discharge ports of the internal injection water metering device D11 and the internal injection admixture metering device D21 are connected to the upstream branch valve 9. Are connected to the first pressure vessel 4a for material injection and the second pressure vessel 4b for material injection, respectively. As a result, the first pressure vessel 4a for material injection and the second pressure vessel 4b for material injection contain water, an admixture, a compressed air, or a mixture thereof.

  Next, the procedure for producing ready-mixed concrete in the batching plant X equipped with such a concrete mixer A will be described while paying attention to the operation and action of the concrete mixer A.

  First, some or all of the blended calculation values according to the type of ready-mixed concrete to be manufactured are used for internal injection water metering device D11, internal injection admixture metering device D21 to internal injection water metering device side pipe D12, for internal injection. The material is injected into the first pressure vessel 4a for material injection through the admixture metering device side pipe D22, and pressure is applied by the compressor 7 (step 1).

  Next, the motor 15 is driven to rotate the mixer shaft 12 (step 2). Then, the amount of water and admixture obtained by subtracting the amount of material injected into the first pressure vessel 4a for material injection from the blended calculation value according to the type of ready-mixed concrete to be produced are supplied from the water metering device D1 and the admixture metering device D2. A discharge port such as a hopper (not shown), that is, an external charging means, is charged from above the kneading tank 11 together with other materials (aggregate, cement, admixture) (step 3). Note that all of the blended calculation values corresponding to the type of ready-mixed concrete to be manufactured in Step 1 were charged from the internal injection water metering device D11 and the internal injection admixture metering device D21 into the material injection first pressure vessel 4a. In this case, in Step 3, only the aggregate, cement, and admixture, which are materials other than water and admixture, are added from above the kneading tank 11. Moreover, the downstream branch valve 52 exists in the said closed state during the process of steps 1-3.

  Simultaneously or substantially simultaneously with the step 3, the downstream branch valve 52 is switched from the closed state to the main pipe open state, and water or an admixture in the first pressure vessel 4a for material injection, or a mixture thereof, It flows into the mixer shaft side pipe line 121 and the arm part side pipe line 131 through the pipe 53 and is injected into the kneading tank 11 from the mixer shaft side discharge port 121a and the arm part side discharge port 131a (step 4). The water or the admixture alone or the mixture thereof in the first pressure vessel 4a for material injection is pushed out to the main pipe 53 by the compressed air when the downstream branch valve 52 is opened, and the mixer shaft side It flows into the pipe line 121 and the arm part side pipe line 131 and is injected into the kneading tank 11 from the mixer shaft side discharge port 121a and the arm part side discharge port 131a. At this time, that is, at the time of Step 4 after passing through Step 2 and Step 3, the raw concrete material has already been put into the kneading tank 11 and has been kneaded by the arm portion 13 and the blades 14, and the mixer shaft. It can be said that water or an admixture alone or a mixture thereof injected from the side discharge port 121a and the arm portion side discharge port 131a is injected from the inside of the ready-mixed concrete. Moreover, the single substance of water or an admixture sprayed from the mixer shaft side discharge port 121a and the arm part side discharge port 131a, or a mixture thereof, is a part of the mixing water of the raw concrete material.

  When the water and the admixture in the first pressure vessel 4a for material injection run out, the compressed air in the first pressure vessel 4a for material injection passes through the main pipe 53 and discharges to the mixer shaft side outlet 121a and the arm side. It is automatically injected from the outlet 131a (step 5). At this time, that is, at the time of Step 5 after Step 4, the ready-mixed concrete material has already been put into the kneading tank 11 and is kneaded by the arm portion 13 and the blade 14, and the mixer shaft side discharge port 121a. And the compressed air injected from the arm part side discharge port 131a can be said to be injected from the inside of the ready-mixed concrete being mixed. Further, the compressed air injected from the mixer shaft side discharge port 121a and the arm unit side discharge port 131a that opens toward the arm unit 13 and the blades 14 is blown toward the arm unit 13 and the blades 14, and the arm unit 13 and the blades It is possible to prevent the mortar content from adhering to 14 excessively. Thereby, the fall of the mixing ability by the mortar part adhering excessively to the arm part 13 and the blade | wing 14 can be prevented, and homogenization of the ready-mixed concrete to manufacture can be aimed at.

  After the compressed air in the material injection first pressure vessel 4a starts to be injected from the mixer shaft side outlet 121a and the arm part side outlet 131a, the downstream branch valve 52 is changed from the main pipe open state to the auxiliary pipe open state. The remaining compressed air in the first pressure vessel 4a for material injection is switched from the discharge port of the auxiliary pipe 8 into the kneading tank 11 (in the atmosphere) (step 6). The timing for switching the downstream branch valve 52 from the main pipe open state to the auxiliary pipe open state, in other words, the time for injecting compressed air from the inside of the ready-mixed concrete is the first pressure vessel for material injection The amount of air injected from within 4a reaches the amount of air required for the ready-mixed ready-mixed concrete, and varies depending on the type of ready-mixed ready-mixed concrete and each batch. Depending on the ready-mixed concrete, the entire amount of compressed air in the first pressure vessel 4a for material injection may be required. In this case, the downstream branch valve 52 is switched from the main pipe open state to the auxiliary pipe open state. Step 6 is not necessary. In this case, the operation in step 7 described below is not necessary.

  After the compressed air is injected from the discharge port of the auxiliary pipe 8 until the predetermined mixing time or until the mixing is completed, the downstream branch valve 52 is switched from the auxiliary pipe open state to the closed state (step 7). In this step 7, all the compressed air in the material injection first pressure vessel 4a is discharged out of the material injection first pressure vessel 4a, and the material injection first pressure vessel 4a is brought to a normal pressure state. It is necessary to keep. This is because in the pressurized state, water, admixture, or a mixture thereof for the next batch cannot be put into the first pressure vessel 4a for material injection. When a predetermined mixing time is reached, a discharge gate (not shown) provided on the bottom wall 114 of the kneading tank 11 is opened, and the volume is visually confirmed with a hopper (not shown) provided below the discharge gate, and then kneaded. When the ready-mixed concrete is discharged toward a track agitator (not shown), the downstream branch valve 52 is switched to the main pipe open state at the same time or substantially simultaneously, and the compressed air in the compressed air dedicated pressure vessel 4c is passed through the main pipe 53 to the mixer shaft side. It ejects from the discharge port 121a and the arm part side discharge port 131a (step 8). In step 8, of the mixer shaft side discharge port 121 a and the arm unit side discharge port 131 a, the injection is performed from the discharge port (mixer shaft side discharge port 121 a, arm unit side discharge port 131 a) that opens toward the arm unit 13 or the blade 14. The compressed air to be blown is naturally blown toward the arm part 13 and the blades 14, and the mortar portion adhering to the arm part 13 and the blades 14 is blown off by the compressed air. Note that if the adhesion amount of the mortar is extremely reduced, the mortar hardens quickly and becomes difficult to clean. Therefore, the pressure of the compressed air is set so that an appropriate amount of the mortar remains in the arm portion 13 and the blade 14 at the end of spraying. Adjust the spraying time as appropriate.

  Simultaneously or substantially simultaneously with the completion of the ready-mixed concrete discharge (within 15 seconds), or after the ready-mixed concrete is completely discharged, the downstream branch valve 52 is switched from the main pipe open state to the closed state (step 9).

  The above steps 1 to 9 are one batch work process.

  Then, water and admixture for the next batch are introduced into the second pressure vessel 4b for material injection in the same manner as in Step 1 and the pressure is applied (Step 10). The steps 2 to 9 are repeated using the second pressure vessel 4b for material injection (step 11). Thus, by providing two pressure vessels for material injection, the time lag from the completion of the discharge of one batch to the start of the mixing operation of the next batch can be reduced as much as possible, which contributes to the improvement of work efficiency. .

  In addition, after completion | finish of the process of the said step 9, or during the process of the said steps 1-7, pressure is applied to the pressure vessel 4c only for compressed air (step 12).

  At the end of production of ready-mixed concrete, in other words, after finishing all batch processing, or when the time to the next batch is long and the attached mortar may be cured, In the case where there is a possibility of adversely affecting the next batch of concrete, only water is poured into the first pressure vessel 4a for material injection and the second pressure vessel 4b for material injection, respectively, and the first pressure vessel 4a for material injection, The downstream branch valve 52 is switched from the closed state to the main pipe open state with the pressure of the second pressure vessel 4b for material injection increased and the mixer shaft 12 rotated, and the mixer shaft side discharge port 121a and the main shaft 53 are opened. High pressure water is jetted from the arm side discharge port 131a toward the arm part 13 and the blades 14 (step 14). In step 14, of the mixer shaft-side discharge port 121a and the arm-portion-side discharge port 131a, the discharge is performed from the discharge ports (mixer-shaft-side discharge port 121a, arm-portion-side discharge port 131a) that open toward the arm portion 13 and the blades 14. Naturally, the high-pressure water to be sprayed is sprayed toward the arm portion 13 and the blades 14, and the high-pressure water is washed off while blowing away the mortar attached to the arm portions 13 and the blades 14. If the cleaning is insufficient, step 14 is repeated.

  As described above, the concrete mixer A according to the present embodiment is provided with the mixer shaft side pipe 121 and the arm part side pipe 131 inside the mixer shaft 12 and the arm part 13, respectively, and the mixer shaft side pipe 121 and the arm. The spraying position of the kneading tank 11 is provided with the spraying means 3 for spraying a single unit of high-pressure water or compressed air or a mixture thereof toward the arm unit 13 and the blades 14 by using the section side conduit 131. The problem that occurs when it is above, that is, the problem that the water pressure is far from the arm part 13 and the blade 14 and the sufficient cleaning cannot be performed is solved, and the arm part 13 and the blade that are difficult to clean. The mortar adhering to 14 can be efficiently cleaned. Furthermore, in comparison with the conventional mode in which the mortar adhering due to the friction of the dedicated metal ring attached to the mixer shaft 12 is suspended, the complicated work of attaching the metal ring to the mixer shaft 12 only at the time of cleaning. In addition to being not required, there is no possibility of wear due to friction or collision between metals, so that it is possible to improve work efficiency during cleaning and prevent early damage of the concrete mixer A itself due to wear. .

  In particular, the mixer shaft side conduit 121 and the arm portion side conduit 131 each have a plurality of mixer shaft side discharge ports 121a and arm portion side discharge ports 131a that open toward the arm portion 13 or the blade 14 respectively. Therefore, the mixer shaft side discharge port 121a and the arm portion side discharge port 131a that open toward the arm unit 13 and the blades 14 are present at positions close to the arm unit 13 and the blades 14 that are the spray target positions. In addition, a single liquid or compressed air that contributes to cleaning or a mixture thereof is sprayed from the mixer shaft side discharge port 121a and the arm unit side discharge port 131a toward the arm unit 13 and the blades 14 at a short distance from a short distance. Can be cleaned more effectively. In addition, the mixer shaft side discharge port 121a and the arm unit side discharge port 131a themselves can be easily formed by drilling the mixer shaft 12 and the arm unit 13, which is excellent in terms of simplification of the structure and ease of processing. It can be said that.

  In addition, since the spraying means 3 uses a pressure vessel (the first pressure vessel 4a for material injection, the second pressure vessel 4b for material injection, the pressure vessel 4c exclusively for compressed air), the first pressure for material injection The arm 4 is improved by increasing the discharge force of water and admixture contained in the container 4a and the second pressure vessel 4b for material injection, or the discharge force of compressed air contained in the compressed air dedicated pressure vessel 4c. 13 and the blade 14 can be more efficiently cleaned, and the discharge pressure can be easily adjusted. A predetermined amount of mortar is applied to the arm 13 and the blade 14. By setting the discharge force to such an extent that it can be adhered, it is possible to prevent the mortar from being blown away more than necessary, and excessive mortar is adhered to the arm 13 and the blades 14 during mixing. It can be preventing.

  Furthermore, the concrete mixer A according to the present embodiment or the batching plant X equipped with the concrete mixer A has an increase in the number of components constituting the spraying means 3 or the existing products with respect to the existing concrete mixer A or batching plant X. It can be realized by processing and remodeling, and it is not necessary to newly install the concrete mixer A itself or the entire batching plant X equipped with the concrete mixer A, and it is extremely difficult in terms of labor and cost of construction work at the time of introduction. It will be advantageous.

  Further, in the concrete mixer A cleaning method according to the present embodiment, when the ready-mixed ready-mixed concrete is discharged out of the kneading tank 11, that is, when each batch is discharged, compressed air is sprayed onto the arm portion 13 and the blade 14 by the spraying means 3. Because of this method, the mortar component adhering to the arm part 13 and the blades 14 can be blown off by blowing compressed air to the arm part 13 and the blades 14 for each batch discharge, and the arm part 13 for each batch discharge. The mortar content adhering to the blades 14 and the blades 14 cannot be cleaned, and the adhering mortar content can be kept at an appropriate amount even between the batches as compared with the conventional mode in which cleaning was performed only after completion of all the batches. Further, by increasing the pressure of the compressed air when the final batch is discharged, the amount of mortar adhering to the arm portion 13 and the blades 14 can be remarkably reduced at the time of cleaning performed after completion of all the batches. As a result, the efficiency of the cleaning operation is improved and the cleaning time can be shortened at the same time. Furthermore, since only the compressed air is blown to the arm part 13 and the blades 14 at the time of discharging each batch, water is unnecessary, and the problem that the wastewater treatment amount increases for each batch discharge can be solved. In addition, by adjusting the discharge pressure of the compressed air for each batch discharge according to the property change and the adhesion amount of the mortar adhering to the arm portion 13 and the blade 14, the adhesion amount of the mortar is blown to an appropriate amount. Can do.

  Furthermore, the cleaning method for the concrete mixer A according to the present embodiment is a method in which high-pressure water is sprayed onto the arm portion 13 and the blades 14 by the spraying means 3 after completion of all the batches, and thus the arm portion 13 that is a portion that is difficult to clean. The mortar part adhering to the blades 14 and the blades 14 can be sprayed from a short distance with high-pressure water discharged from the mixer shaft side discharge port 121a and the arm unit side discharge port 131a. Can be efficiently performed, and the cleaning time can be shortened.

  Moreover, since the manufacturing method of the ready-mixed concrete which concerns on this embodiment is a method of spraying the compressed air which contributes to washing | cleaning with the said spraying means 3 at the time of each batch discharge to the arm part 13 and the blade | wing 14, it is difficult to wash | clean for every batch. The mortar part adhering to the arm part 13 and the blades 14 which are parts can be blown off, which not only contributes to the reduction of the work load at the time of cleaning, but also the mortar part remaining in the mixer is always maintained in an appropriate amount, so that each Contributes to homogenization of ready-mixed concrete discharged in batches. In addition, the cleaning operation after kneading (after completion of all batches) can be performed efficiently, which contributes greatly to shortening the cleaning time.

  The present invention is not limited to the embodiment described in detail above.

  For example, as a “liquid that contributes to cleaning”, spraying means sprays toward the arm part and blades using a pipeline, instead of the water mentioned in the above embodiment, an admixture that is a raw concrete material, or A special cleaning agent may be applied. Moreover, the mixture of water and an admixture may be sufficient.

  In addition, a pipe (blade side pipe) is also provided inside the vane, and the spraying means also uses this pipe (blade side pipe), and the liquid or air that contributes to cleaning, or a mixture thereof You may spray a body toward an arm part and a blade | wing. In this case, the blade side pipe line has a plurality of blade side discharge ports opened in the kneading tank, and if the opening direction of these blade side discharge ports is set in a direction facing the arm part or other blades, A simple substance of liquid or air ejected from the blade-side discharge port, or a mixture thereof can be sprayed toward the arm portion and the blade.

  Further, when the spraying means is constituted by using a pressure vessel, an embodiment in which a single or three or more material injection pressure vessels are used, an embodiment in which two or more compressed air dedicated pressure vessels are used, or a material injection pressure vessel is used. A mode of diverting to a compressed air dedicated pressure vessel may also be used.

  Moreover, the opening diameter of each pipe line and the opening diameter and number of each discharge port may be changed as appropriate, and the pipe diameter of each pipe, the capacity of the pressure vessel, and the capacity of the compressor are determined from the capacity of the batching plant. May be determined as appropriate.

  Also, the spraying means is provided with a plurality of nozzles provided with communication pipes communicating with each pipe line (mixer shaft side pipe line, arm part side pipe line) at least on the mixer shaft and the arm part, A single air or a mixture thereof may be blown toward the arm portion and the blade. In this case, each nozzle may be selectable or switchable from a plurality of spraying modes by a predetermined operation. As a spraying mode, a normal spraying mode serving as a reference, a wide-angle (diffusion) spraying mode capable of spraying over a wider angle than the normal spraying mode, and a high-pressure spraying mode capable of spraying at a higher pressure than the normal spraying mode Is mentioned. If each nozzle can be attached to and removed from at least the mixer shaft and arm, it is only necessary to replace the nozzle that has failed its original function or a damaged nozzle with a new nozzle. Compared with an aspect in which the entire part is forced to be replaced, labor and cost for replacement work and maintenance work can be reduced.

  In the above embodiment, the liquid (high pressure water) is sprayed and washed on the arm part and the blade only after “all batches are finished”, but the ready-mixed concrete kneaded in the kneading tank is moved out of the kneading tank. A mode in which liquid (high-pressure water) is sprayed onto the arm portion and the blades and cleaned after each discharge or periodically may be used.

  Further, the spraying means may spray a mixture of liquid and compressed air that contributes to cleaning toward the arm portion and the blades.

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

1 is an overall schematic view of a batching plant including a concrete mixer according to an embodiment of the present invention. The figure which abbreviate | omits a part of the cross section of the concrete mixer which concerns on the same embodiment, and shows typically. The whole schematic diagram of the batching plant provided with the conventional concrete mixer.

Explanation of symbols

A ... Concrete mixer 11 ... Kneading tank 12 ... Mixer shaft 13 ... Arm part 14 ... Blades 121, 131 ... Pipe line (mixer shaft side pipe line, arm part side pipe line)
121a, 131a ... discharge port (mixer shaft side discharge port, arm unit side discharge port)
3 ... spraying means 4a, 4b, 4c ... pressure vessel (first pressure vessel for material injection, second pressure vessel for material injection, pressure vessel exclusively for compressed air)

Claims (6)

A compulsory for producing ready-mixed concrete comprising a kneading tank, a pair of mixer shafts rotatable around a horizontal axis in the kneading tank, an arm portion provided on each mixer shaft, and a blade provided on each arm portion Type horizontal biaxial concrete mixer,
A pipe is provided at least inside the mixer shaft and the arm,
A concrete mixer characterized by comprising spray means for spraying a liquid or air that contributes to cleaning, or a mixture thereof toward the arm part and the blades by using these pipes. The concrete mixer according to claim 1, wherein each of the pipes provided in the mixer shaft and the arm portion has a plurality of discharge ports that open toward the arm portion or the blades. The concrete mixer according to claim 1 or 2, wherein the spraying means uses a pressure vessel containing only liquid and compressed air contributing to cleaning, or compressed air. A concrete mixer cleaning method for cleaning a concrete mixer according to any one of claims 1 to 3,
A method for cleaning a concrete mixer, characterized in that air that contributes to cleaning is blown to the arm portion and the blades by the spraying means when at least the ready-mixed concrete kneaded in the kneading tank is discharged out of the kneading tank. A concrete mixer cleaning method for cleaning a concrete mixer according to any one of claims 1 to 3,
A method for cleaning a concrete mixer, characterized in that a liquid that contributes to cleaning is sprayed onto the arm part and the blades by the spraying means after mixing. A method for producing ready-mixed concrete using the concrete mixer according to claim 1,
A method for producing ready-mixed concrete, characterized in that air that contributes to cleaning is blown to the arm portion and the blades by the spraying means when at least discharging ready-mixed concrete in a kneading tank to the outside of the kneading tank.

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