JP5105202B2 - Fluid conveying device - Google Patents

Description

  The present invention relates to a fluid transport device for transporting a fluid, particularly concrete, by installing a boom or a direct transport pipe at a specific site such as a high place or a long distance at each site of civil engineering and construction.

  In a conventional fluid conveyance device, for example, a concrete pump described in Patent Document 1, a fluid such as concrete or earth and sand is sucked and discharged to convey the fluid to an unspecified place such as a long distance or high place. As shown in FIG. 8, the concrete pistons 1a and 2a are alternately reciprocated by the hydraulic cylinders 11 and 12 to suck and discharge the concrete. As shown in FIG. 8, the hydraulic cylinders 11 and 12 are provided with hydraulic piping from the hydraulic switching valve 17 only on the rear side, and the front side connects the hydraulic cylinders 11 and 12 with the piping 15. The front pressure oil is coming and going. As a result, when the pressure behind the hydraulic cylinder 11 becomes high and the pressure behind the hydraulic cylinder 12 becomes low, the concrete piston 1a moves forward to the concrete cylinder discharge port 1b and becomes a discharge stroke, and the concrete piston 2a moves backward from the concrete cylinder discharge port 2b. The inhalation process. The communication switching pipe 6 connected to the concrete cylinders 1 and 2 is driven by the hydraulic cylinder 7 so as to communicate with either one of the concrete cylinder discharge ports 1b and 2b with the transport pipe 5 as a fulcrum.

  When the concrete piston 1a moves forward in the above state, the communication switching pipe 6 is switched to the concrete cylinder discharge port 1b and feeds the concrete in the concrete cylinder 1 to the transport pipe 5. The concrete cylinder 2 sucks concrete from the concrete reservoir 4, that is, a suction process. In this state, when the piston 11a of the hydraulic cylinder 11 advances and reaches the stroke end detection sensor 13, the switching valve 10 is switched, the hydraulic cylinder 7 is operated, and the communication switching pipe 6 is switched. When the hydraulic cylinder 7 is actuated and the piston 7a reaches the stroke end detection sensor 8, the hydraulic pressure switching valve 17 is switched, so that the pressure behind the hydraulic cylinder 12 becomes high and the concrete piston 2a moves forward. Concrete can be transported continuously in such a cycle.

  As a hydraulic pump, there is a high-pressure, high-discharge hydraulic pump called an axial plunger pump (hydraulic piston pump) described in Patent Document 2. The structure is such that a cylindrical cylinder block is installed in a rotatable state in the casing forming the main body, a rotation shaft is provided at the center of the cylinder block, and the rotation shaft is fitted and fixed to the cylinder block. One of the rotating shafts protrudes outside one of the casings, and the rotating shaft is driven to rotate by a driving force. A plurality of elongated vertical holes, which are cylinder bores, are provided in parallel in the cylinder block, and a piston is removably inserted into the cylinder bore. A Shu is installed on one of the spheres of the piston so that it can swing, and a disc-shaped swash plate with a hole through which the rotation shaft is inserted is installed at the center between the casing and the cylinder block. A shoe with the surface of the swash plate installed on the spherical part of the piston slides. As the cylinder block rotates, the shoe installed on the piston slides on the swash plate, so that the piston reciprocates in the cylinder bore.

  Hydraulic fluid is sucked and discharged by the above operation. A valve plate having a disk-shaped suction port opened in a circular arc shape on the left half smaller than the semicircular shape between the other cylinder block longitudinal direction and the casing and a discharge port of the same shape on the right half is fixedly installed on the casing. . Holes penetrating outside the casing are provided on the other side of the casing, and the left and right holes communicate with the arc-shaped elongated holes of the valve plate. While the cylinder block makes one revolution, the shoe at the tip of the piston in the cylinder bore facing the suction port in the left half descends the swash plate surface, so the piston moves backward in the cylinder bore, and the shoe in the right half is the swash plate. The piston moves forward in the cylinder bore to ascend the surface. As the cylinder block rotates, the shoe slides on the swash plate and reciprocates in each cylinder bore while the piston makes a half-turn to suck in oil from the suction port. Oil can be discharged without interruption.

JP 2002-322980 A JP 2006-207501 A JP-A-11-247224

  However, in the conventional concrete pump described in Patent Document 1, although the transfer work can be continuously performed, when the movement of the piston of the hydraulic cylinder 11 is switched once when the forward stroke and the backward stroke are switched, a large impact is caused when the movement starts again. Is generated. The switching of the communication pipe also generates an impact. For concrete transport work, the boom and transport device are attached to the car and transport work is performed. As described above, the impact of the movement of the piston or the switching of the communication pipe occurs as described above for each operation process during the transport operation, and the vehicle shakes and the boom swings greatly. For this reason, workability is poor and cracks occur in various places such as cars, conveyors, and booms. In particular, if a crack breakage accident occurs in the boom, it becomes a serious accident such as a loss of human life, which is a serious social problem. In order to solve the problem, each concrete pump manufacturer has made various modifications. For example, a manufacturer communicates a pressure with a maximum pressure of 28 MPa in order to reduce the impact when the concrete piston 1a, 2a stops once when the forward stroke and the backward stroke are switched when the communication pipe 6 is switched. Only when the tube is switched, the pressure is reduced to 5 MPa to reduce the impact as much as possible. In addition, in order to reduce boom swing, other manufacturers have installed a damping device to automatically raise and lower the pressure behind the hydraulic cylinder of the NO1 boom in accordance with the vertical swing of the boom to reduce boom vibration. . However, those effects are not enough, and there is still a boom breakage accident.

  The axial plunger pump described in Patent Document 2 is a high-pressure, high-discharge pump that can continuously send out liquids such as oil and water at high pressure without causing large vibrations. However, the amount of liquid delivered is determined by the piston stroke, and the stroke is determined by the angle of the swash plate. Therefore, a large piston stroke cannot be obtained. Need to speed up the movement. If the liquid has a low viscosity, it can be sucked into the cylinder bore when it rotates at a high speed and the piston moves fast, but it is impossible to suck a high viscosity material such as concrete. Further, since the piston reciprocates as the shoe slides on the swash plate as the cylinder block rotates, the movement of the piston cannot be stopped. There is no hole at the middle position between the arc-shaped suction port and discharge port of the valve plate, and the opening of the cylinder bore that has been rotated to that position is sealed and becomes a confining pressure. The confinement pressure is released by a small relief hole from the position between the suction port and the discharge port between the arcuate shape of the valve plate toward the low pressure side. The solid matter with a coarse particle size, that is, the pressure does not escape and becomes clogged. In addition, a valve plate installed on one side of the cylinder block in the longitudinal direction separates the intake port and the discharge port, and the sealing of the contact surface between the cylinder block and the valve plate is important. Solid material enters this contact surface. When the contact surface is damaged, a gap is formed, and both the discharge amount and the discharge pressure are reduced. An axial plunger pump is a pump that can transport fluids at high discharge and high pressure without interruption, but because of the above conditions, an axial plunger pump is used to produce fluids with high viscosity and coarse particle size like concrete. It is impossible to carry.

  The present invention has been made in view of the above circumstances, and provides a fluid conveyance device that has little impact when conveying a fluid that contains a large amount of coarse particles with high viscosity, such as concrete, and that has little boom swing. For the purpose.

A device for pumping a fluid having a high viscosity and a coarse particle size, such as concrete according to claim 1, wherein a plurality of reciprocating pumps composed of a concrete cylinder, a concrete piston, and a hydraulic cylinder rotate concentrically around a center axis. In the fluid pressure feeding device arranged in parallel to the drum, a face plate provided at one end in the longitudinal direction of the drum and having an opening communicating with the concrete cylinder of each of the reciprocating pumps, and the hydraulic cylinder by detecting the rotation of the drum And a valve mechanism that covers the opening of the face plate in the boundary region between the suction side and the discharge side, and the valve mechanism is a partition built in a valve case provided between the suction side and the discharge side. The partition board is in contact with the rotating face plate and completely covers the face plate opening. The fluid is prevented from flowing from the discharge side to the suction side, and is kept in contact with the face plate by the pressing mechanism. It is possible to prevent a gap from being raised and the face plate, and to prevent backflow of the high-pressure concrete from the discharge side to the suction side.

  The fluid conveyance device according to claim 2 is characterized in that the partition plate built in the valve case rotates the partition plate itself, and reduces uneven wear of the sliding contact portion between the face plate and the partition plate. Thus, even if the wear amount of both increases during long-term use, it is possible to prevent the sliding contact portion between the face plate and the partition board from being worn on average and to generate a gap between the sliding contact portion between the face plate and the partition board.

  In the fluid conveying apparatus of the present invention, a reciprocating pump is installed in parallel on a plurality of circumferences of the drum, the drum is rotated, and the reciprocating pump is driven in synchronization with the rotation of the drum to suck and discharge the fluid. Due to the valve function of the valve case at the top of the face plate and the action of a mechanism that switches the hydraulic pressure in synchronization with the rotation of the drum, the drum rotates, so that multiple reciprocating pumps sequentially suck in the fluid on the suction side and suck on the suction side Fluid is sent out on the discharge side, passes through the discharge case, passes through the transport pipe, and pumps the concrete. During operation, one or more reciprocating pumps are always driven on the suction side and discharge side, so that the flow of concrete can be transported without interruption, and fluid can be transported with almost no impact or boom swing. When working at a high place to reduce the hydraulic oil discharge capacity and reduce the concrete discharge amount, the fluid transport device of the present invention has a partition as a valve mechanism in the boundary area between the suction side and the discharge side. Since the opening is covered and no gap is generated between the partition board and the face plate, the concrete in the transport pipe does not flow back into the hopper by the back pressure.

Sectional drawing of the principal part of the conveying apparatus of this invention The perspective view of the conveying apparatus of this invention Operation state diagram of face plate opening and partition, concrete cylinder and concrete piston The perspective view of the swivel type hydraulic switching valve of the present invention Sectional view of the swivel type hydraulic switching valve of the present invention External view of a boom-mounted pump truck installed with the transport device of the present invention External view of a conventional boom-equipped pump truck Conventional concrete conveyor

  Like the axial plunger pump, the present invention adopts a structure in which a plurality of reciprocating pumps are arranged in parallel on the circumference in a rotating drum, and a hydraulically driven reciprocating pump used in a conventional concrete pump is used. It was completed by adding many newly developed technologies on top of it, and as a fluid conveyance device embodiment of the present invention, it is composed of a drum 14, a concrete cylinder 15, a suction part, a discharge part, a hydraulic use part, etc. The concrete conveying apparatus to perform is shown in FIG. A reciprocating pump is formed by combining the concrete cylinder 15, the concrete piston 16, and the hydraulic cylinder 17. In order to perform a stable pumping operation, the number of reciprocating pumps is preferably 5 or more and odd. However, FIG. 1 is a cross-sectional view of an example of four reciprocating pumps in order to facilitate understanding of the structure of the fluid conveyance device of the present invention, and FIGS.

  1 has a center shaft in the center of the horizontal outer cylinder 27, and the center shaft passes through three disc-shaped iron plates including an iron plate to which the face plate 26 is attached. There is a drum 14 in which a plurality of reciprocating pumps are concentrically arranged in parallel on the above three iron plates around the center axis, and the concrete cylinder 15 is opened to the face plate 26 in which the number of openings of the concrete cylinder 15 is opened. The department is in communication. The valve case 21 is fixed to the horizontal outer cylinder 27 at the upper portion of the one face plate 26 of the drum 14, and the swivel hydraulic switching valve 23 is attached to the center shaft at the other end of the drum 14. It is desirable that a pressure oil supply pipe is installed in the hydraulic cylinder 17 of the reciprocating pump installed in the drum 14 from 23, and at least a part of the center shaft becomes hollow and is provided to the pipe.

  The drum 14 rotates about the center axis. In synchronism with the rotation of the drum 14, the hydraulic cylinder rod 18 travels and the concrete piston 16 attached to the hydraulic cylinder rod 18 also reciprocates in the concrete cylinder 15 to communicate with the opening portion of the concrete cylinder 15. Fluid can be sucked and discharged from the opening. When the concrete piston 16 in the concrete cylinder 15 communicating with the opening of the face plate 26 under the partition plate 20 installed in the valve case 21 is moved from the discharge side 30 to the suction side 29 by the rotation of the drum, While passing under the partition, it moves forward to the stroke end and stops. Further, when moving from the suction side 29 to the discharge side 30, while the concrete piston 16 passes under the partition board, it moves backward to the stroke start point and stops.

  The valve case 21 is located between the suction side 29 and the discharge side 30 and divides both areas and incorporates a partition 20 at both ends. When the opening of the face plate 26 reaches the boundary area between the suction side and the discharge side due to the rotation of the drum. Further, the opening of the face plate 26 is completely covered with the partition plate 20, and the partition plate 20 prevents a fluid such as high-pressure concrete from flowing from the discharge side 30 to the suction side 29 through the opening of the face plate 26. It becomes. If the concrete piston 16 moves with the opening of the face plate 26 completely covered under the partition board 20, when the concrete piston 16 moves from the suction side 29 to the discharge side, the inside of the concrete cylinder becomes negative pressure, and the discharge side 30 leads to the suction side. When moving to 29, the inside of the concrete cylinder becomes confined pressure, which makes it difficult to operate the transport device. Therefore, in the present invention, in order to avoid a confining pressure and a negative pressure state, the concrete piston 16 is always stopped when at least the opening of the face plate 26 rotates below the partition board 20. Yes. Since the face plate 26 is installed on the drum 14, it rotates together with the drum 14. The face plate 26 rotates at the center of one end in the longitudinal direction of the horizontal outer cylinder 27. The place where the face plate 26 rotates at the center of one end in the longitudinal direction of the horizontal outer cylinder 27 is referred to as a horizontal outer cylinder 27 face plate 26 rotating portion.

  As shown in FIG. 2, the valve case 21 is attached to the horizontal outer cylinder so that the partition plate 20 is in sliding contact with the face plate 26 located on the upper center line of the face plate 26 at one end in the longitudinal direction of the drum 14. A region on the face plate 26 at one end in the longitudinal direction of the horizontal outer cylinder 27 is divided into a suction side 29 and a discharge side 30 with the valve case 21 as a boundary. A box (hereinafter referred to as a hopper) whose upper part spreads open in a trumpet shape is provided on one suction side 29 of the upper part of the face plate 26 divided by the valve case 21 (not shown in each figure). The concrete collected by the concrete transport vehicle is sucked into the concrete cylinder that has rotated to the suction side.

  The discharge case 28 shown in FIG. 2 is a case attached to the discharge side 30 and is attached to the valve case 21 and the horizontal outer cylinder 27 in a sealed state except for the discharge port. The concrete is sucked into the concrete cylinder 15 of the reciprocating pump located on the suction side 29, rotated to the discharge side 30 by the rotation of the drum 14 that is always rotating, and the hydraulic cylinder 17 is operated on the discharge side 30, thereby supplying the concrete. The discharge case 29 is discharged and filled with high pressure, and the concrete is conveyed through a transport pipe installed from the discharge port to a concrete placement site, such as far away or at a high place. The opening of one face plate 26 in the longitudinal direction of the drum 14 communicates with each concrete cylinder 15, and the concrete piston 16 of the reciprocating pump that has been rotated to the suction side 29 by the rotation of the drum 14 moves backward to collect the fluid. The suction / inhalation process is performed, and the concrete piston 16 of the reciprocating pump that has rotated to the discharge side 30 moves forward to discharge the fluid and the discharge process.

  A characteristic operation of the fluid conveyance device of the present invention described in FIG. 3 will be described for one of a plurality of reciprocating pumps in accordance with the rotation of the drum 14. On the suction side 29, the drum 14 rotates around the center axis, and the concrete piston 16 moves backward to suck the fluid into the concrete cylinder 15. When the opening of the face plate 26 that reaches one partition board 20 and communicates with the opening of the concrete cylinder 15 is covered with, for example, half the diameter by the partition board 20, the concrete piston 16 moves back to the stroke start point and stops. After the face plate 26 rotates in a sliding contact with the partition plate 20 for a predetermined time, the concrete piston 16 continues to be stopped, and then the drum 14 further rotates so that about half of the opening of the face plate 26 is from below the partition plate 20. When the concrete piston 16 comes out to the discharge side, the concrete piston 16 starts moving in the forward direction, and the fluid in the concrete cylinder 15 is discharged. Further, when the drum 14 is rotated and the other partition plate is covered by about half of the opening of the face plate 16, the concrete piston 16 that has advanced advances to the stroke end and stops. In this way, the plurality of reciprocating pumps can convey the fluid without interruption by repeating the cycles of the suction process, the stopped state, and the discharge process in synchronization with the rotation of the drum 14. In order to make the conveyance of the fluid more stable, it is desirable that the number of reciprocating pumps is large and that it is an odd number.

FIG. 3 shows the relationship between the opening of the face plate 26 and the position of the reciprocating pump, and the position of the concrete piston 16 and the operating state of the reciprocating pump. FIG. 3a shows the relationship between the openings A, B, C, D and E of the face plate 26 and the two partition plates 20 at the rotation positions of the drum 14 every 90 degrees, and FIG. The movement of the concrete piston 16 is shown.
The opening A of NO1 is covered with the partition board 20, and the concrete piston 16 in the reciprocating pump advances to the stroke end and stops. In the reciprocating pumps of the openings B and C, the concrete piston 16 moves backward to enter the suction process. In the reciprocating pumps of the openings D and E, the concrete piston 16 moves forward and becomes a discharge process.

In the state of NO2 in which the drum 14 is rotated 90 degrees from the state of NO1, the reciprocating pump of the opening A is in the suction process with the concrete piston 16 retreating, and the opening B is just before being covered by the partition board 20, In the reciprocating pump of part B, the concrete piston 16 moves back to the stroke start point and stops. The concrete piston 16 of the reciprocating pump of the openings C and D moves forward and becomes a discharge process. Since most of the opening E is covered with the partition board 20, the reciprocating pump of the opening E stops when the concrete piston 16 advances to the stroke end.

  Furthermore, in the state of NO3 in which the drum 14 is rotated 90 degrees, the reciprocating pump of the opening A covered with the partition board 20 stops with the concrete piston 16 retracting to the stroke start point. The reciprocating pumps of the openings B and C enter the discharge process when the concrete piston 16 moves forward, and the reciprocating pump of the opening C whose area already covered by the partition board 20 has increased is just before the concrete stone 16 stops while moving forward. It is in. In the reciprocating pumps of the openings D and E, the concrete piston 16 retreats and the suction process is performed. However, in the reciprocating pump of the opening D in which the area covered by the partition board 20 is reduced, the concrete piston 16 moves in the retreating direction. I just started.

  In the state of NO4 in which the drum 14 is further rotated by 90 degrees, the reciprocating pump of the opening A enters the discharging process with the concrete piston 16 moving forward, and the reciprocating pump of the opening B whose partitioning plate covers more than half is a concrete piston. 16 advances to the stroke end and stops. In the reciprocating pumps of the openings C and D, the concrete piston 16 moves backward to enter the suction process. In the reciprocating pump of the opening E, the concrete piston 16 moves back to the stroke start point and is covered with the partition board 20 and stopped. Further, the state returns to the state of NO1 by NO5 in which the drum 14 is rotated 90 degrees.

  By rotating the drum 14 in this manner, the concrete pistons 16 of the plurality of reciprocating pumps are sequentially retracted on the suction side to enter the suction process, and the concrete pistons of the plurality of reciprocating pumps are sequentially advanced on the discharge side 30 to the discharge process. Become. As can be seen in FIG. 3, during the rotation of the drum on the suction side 29 and the discharge side 30, the concrete piston 16 of at least one reciprocating pump is always operating, so that suction and discharge are performed without interruption. In the transition region between the suction side 29 and the discharge side 30, the concrete piston 16 in the concrete cylinder 15 is stopped by the reciprocating pump of the opening that has come under the partition 20. If the concrete piston 16 retreats in the concrete cylinder 15 communicating with the opening under the partition 20, the inside of the concrete cylinder becomes negative pressure, and if the concrete piston 16 moves forward in the concrete cylinder 15, it becomes confined pressure, which hinders operation. Bring However, in the fluid conveyance device of the present invention, the concrete piston 16 in the concrete cylinder 15 communicating with the opening covered by the partition board 20 stops for a predetermined time, so that the inside of the concrete cylinder 15 becomes negative pressure or confinement pressure. There is no.

  As described above, the concrete in the concrete cylinder 15 of the reciprocating pump is discharged into the discharge case 28 by the concrete piston 16, and the concrete is discharged from the discharge port of the discharge case 28 connected to the transport pipe. Since the concrete is discharged from the concrete cylinder 15 while the drum 14 rotates, the concrete discharged from the concrete cylinder 15 flows along the rotation of the drum 14, and a concrete flow path is formed in the discharge case 28. In order to reduce the resistance of the flow of the concrete and reduce the wear of the discharge case 28, the discharge case 28 having a shape imitating the flow path of the concrete is desirable. The discharge case 28 is attached to the horizontal outer cylinder 27 and the valve case 21.

The valve case 21 is attached to the rotating portion of the lateral outer cylinder 27 face plate 26. A bearing 35 is provided at the center of the valve case 21 for rotation and support of the center shaft of the drum 14, and a seal 36 is also provided in the bearing portion to prevent fluid from entering. Partition plates 20 are provided at both ends in the longitudinal direction of the valve case 21 and are in contact with one main surface of the face plate 26. The face plate 26 is installed on one side in the longitudinal direction of the drum 14, and the face plate 26 also rotates as the drum 14 rotates. A plurality of openings are formed in the face plate 26, and each opening communicates with each of the opening portions of the concrete cylinder 15. The suction side 29 and the discharge side 30 are separated by the valve case 21 and communicated only with the partition plate 20 and the face plate 26 contact portion. The face plate 26 rotates and the openings of the face plates 26 move to the partition plate 20. Then, the opening part of the face plate 26 that has moved is completely covered by the partition board 20. Since the partition plate 20 and the face plate 26 come into contact with each other and the opening of the face plate 26 is completely covered with the partition plate 20, the suction side 29 and the discharge side 30 are blocked.

  The contact degree between the partition board 20 and the face plate 26 is important. However, when a part of the opening of the face plate 26 is covered with the partition plate 20 and the other part is still exposed to the discharge side 30, the high pressure of the fluid on the discharge side 30 passes through the opening of the face plate 26. Take 20 As a result, a force that pushes up the partition plate 20 is generated and the partition plate 20 is lifted, and the high-pressure fluid on the discharge side 30 is ejected to the suction side 29 from the gap formed on the sliding contact surface between the partition plate 20 and the face plate 26. In order to prevent this, spring chambers 28a and 28b are provided in the shaft portion of the partition board 20, the partition board 20 is pressed against the face plate 26 with a spring, and pressure oil is further introduced into the spring chambers 28a and 28b by the force of the pressure oil. A pressing mechanism is provided, such as pressing the surface plate 26 against the face plate 26. By providing a check valve 32 in the pressure oil replenishment circuit to be put in the spring chambers 28a and 28b, the spring chambers 28a and 28b become sealed chambers and the oil does not shrink, thereby preventing the partition 20 from being pushed up. It is also possible to provide a pressing mechanism for fixing and adjusting the partition plate to the face plate 26 mechanically using a bolt or the like.

  The fluid transported by the fluid transport device of this embodiment is mostly concrete, and the components of the concrete are composed of coarse aggregate, fine aggregate, cement, additives, etc., and the particle size is rough and highly viscous. Since the board 20 abuts against the face plate 26 and the face plate 26 rotates to constantly feed the concrete at a high pressure, the abutment surface between the partition board 20 and the face plate 26 is worn. In order to reduce the wear, a hard-wearing material such as cemented carbide is used. However, the contact surface between the partition board 20 and the face plate 26 is always worn. There is no problem if it wears uniformly, but it does not wear evenly, such as inside and outside of the partition board 20, inside and outside of the face plate 26, and the opening of the face plate 26, and wears unevenly and forms part of the contact surface between the partition board 20 and the face plate 26. A gap is formed, and the concrete is ejected to the suction side 29 through the gap formed between the partition board 20 face plates 26, thereby hindering conveyance.

  The partition plate 20 and the face plate 26 each wear unevenly because the speed is different between the inside of the face plate 26, that is, the vicinity of the center axis side of the drum 14 and the outside, that is, the side of the lateral outer cylinder 27. The outer side is more worn than the inner side where the rotation speed is slow, which is uneven wear. In order to reduce the uneven wear, when the partition plate 20 is formed in a disk shape and the partition plate 20 itself is rotated while being in contact with the face plate 26, the contact surfaces of the partition plate 20 and the face plate 26 come into contact with each other on average. The uneven wear of the surface is extremely reduced, and the partition board 20 face plate 26 can be used up to the wear limit and is economical. Various methods such as hydraulic, electric, and manual can be used to rotate the partition 20 itself. In the fluid device of this embodiment, a gear 33 is attached to the tip of the shaft of both partitions 20 and the drum 14 is attached. A gear 22 is attached to the tip of the center shaft of the drum 14 and the gear 33 and the gear 22 are combined to rotate the partition 20 by rotating the center shaft of the drum 14. However, if the divider 20 rotates in the same direction as the drum 14, the rotation speed is high, and this alone causes wear of the divider 20.

  Therefore, the gear 22 has only one tooth and the gear 22 is always rotating. However, the left and right gears 33 rotate only when the gear 22 has only one tooth, and the gear 22 has no teeth. Since the gear 33 does not rotate at this point, the partition 20 rotates only slightly even if the drum 14 rotates once. As the partition plate 20 rotates, the inner and outer sides of the partition plate 20 abut on the face plate 26 on average, so that both contact surfaces of the partition plate 20 face plate 26 have very little wear. Further, as described above, pressure oil always enters the spring chambers 28a and 28b, the partition plate 20 is pressed against the face plate 26 by the pressure oil and spring force of the spring chambers 28a and 28b, and the partition plate 20 and the face plate are pressed by the pressing force. Even if 26 is worn, the partition plate 20 does not advance to the face plate 26 and the gap between the partition plate 20 and the face plate 26 does not increase.

  The present embodiment is characterized in that in the first embodiment described above, a hydraulic control mechanism that causes the hydraulic cylinder rods 18 of the five reciprocating pumps to reciprocate alternately on the suction side and the discharge side in synchronism with the rotation of the drum 14. It is. In order for the hydraulic cylinder rod 18 attached with the concrete piston 16 in synchronism with the rotation of the drum 14 to alternately reciprocate between the suction side and the discharge side, the rotation of the drum 14 is sensed (with a limit switch or the like) and hydraulic pressure is detected. By switching the switching valve, the hydraulic oil must be sent from the fixed hydraulic pressure generator to the hydraulic cylinder 17 installed on the rotating drum 14. Conventionally, a device called a swivel joint is used to send pressure oil from a non-rotating object to a rotating object. In this embodiment, the function of a swivel joint that sends hydraulic pressure from a fixed hydraulic pressure generator to a hydraulic cylinder 17 of a reciprocating pump installed on a rotating drum 14 and the hydraulic pressure is switched by detecting the rotation of the drum 14. A novel swivel-type hydraulic switching valve 23 characterized by being capable of switching the pressure oil to be sent to the cylinder 17 with a single device is adopted.

  Patent Document 3 describes a swivel joint device used in a wheeled hydraulic excavator provided with a steering device. In this swivel joint device, two large and small oil chambers are formed which are fixed to the lower traveling body and provided radially on the circumferential side of the cylindrical main body and divided by two partitions, and are stored in the main body. The spindle rotates with the swivel body, and the oil passage on the main body side that the opening of the oil passage opposes is replaced. Therefore, if the steering operation is performed in the direction of turning while the driver's seat is turned in the direction opposite to the forward direction, the machine can move in that direction. However, the swivel joint switches the hydraulic circuit only when the revolving body is switched between the forward direction and the reverse direction, and does not always rotate and switch the hydraulic pressure in synchronization with the rotation.

  The swivel-type hydraulic switching valve 23 of the present invention is a combination of the outer cylinder 24 of the swivel-type hydraulic switching valve 23 (hereinafter referred to as the outer cylinder 24) and the middle cylinder 25 of the swivel-type hydraulic switching valve 23 (hereinafter referred to as the middle cylinder 25). As shown in FIG. 1 and FIG. 5, a middle cylinder 25 is incorporated in the outer cylinder 24. The outer cylinder 24 is fixed to the horizontal outer cylinder 27 and does not move. The middle cylinder 25 is fitted and fixed to the center shaft of the drum 14, rotates together with the drum 14, and pipes are connected to the hydraulic cylinder 17 attached to the drum 14 from the middle cylinder 25. Pipes are connected to the outer cylinders 24 from the respective electrohydraulic switching valves (not shown in the drawings) to the ports 6, 7, 8, and 9 of the outer cylinder 24 so that high-pressure oil enters and exits. In order to feed the hydraulic pipe from the inner wall of the middle cylinder to the hydraulic cylinder 17, the center shaft is tubular and the hydraulic pipe can penetrate the pipe wall.

4 and 5, the swivel-type hydraulic pressure switching valve 23 of the present invention will be described.
In order for the hydraulic cylinder rod 18 to reciprocate in synchronization with the rotation of the drum 14, a hydraulic switching valve is required, and the hydraulic pressure is also switched by the swivel hydraulic switching valve 23. The contact surface of the middle cylinder 25 and the outer cylinder 24, that is, the longitudinal direction of the outer wall of the middle cylinder 25 is set at equally spaced positions. A vertical hole in which two horizontal holes Ia and Ja are provided in the middle cylinder 25 at the positions of I and J and in the same longitudinal direction at the middle of the thickness of the middle cylinder in parallel with the inner holes facing inward. Five inverted F-type through-holes communicating with the hole N are formed. Further, two F-shaped communication holes are formed by connecting the two horizontal holes Ka and La at the same position in the vertical direction with the vertical holes M provided in the inner cylinder 25 at the positions K and L. Further, each hole Ia located at I of the middle cylinder 25 is penetrated to the inner wall, and a pipe is passed from the hole on the inner wall to the tubular center shaft of the drum 14 to reach the front of the hydraulic cylinder. Further, each hole La located at L is also penetrated to the inside of the middle cylinder 25 to pass the pipe through the tubular center shaft of the drum 14. Install. Although the open ends of the vertical holes N and M provided in the middle cylinder 25 are sealed, piping can be installed from the open ends of the vertical holes N and M to the hydraulic cylinder depending on the size of the machine.

  The contact surface of the outer cylinder 24 and the inner cylinder 25, that is, the inner wall of the outer cylinder 24 is also formed on the semi-inner surface on the left side in the longitudinal direction of the outer cylinder 24 corresponding to the positions I and K in the longitudinal direction of the inner cylinder 25. Arc-shaped transverse grooves P and R are provided, and arc-shaped transverse grooves Q and S having a length less than half of the circumferential length are provided on the inner surface on the right side in the longitudinal direction of the inner wall of the outer cylinder 24 corresponding to the positions J and L in the longitudinal direction of the middle cylinder 25. As shown in FIG. 5A, there is a portion where no lateral groove is provided between the left circular arc-shaped horizontal groove P and the right circular arc-shaped horizontal groove Q when viewed in the axial direction. That is the piston stop O. The ratio of the length of the piston stop portion O to the circumferential length of the semi-inner surface of the outer cylinder 24 is determined by the stop time of the concrete piston in the first embodiment. In other words, the stop time of the concrete piston can be determined by the length of the lateral groove. The combination of the outer cylinder 24 and the middle cylinder 25 as described above causes the hydraulic cylinder rod 18 to reciprocate alternately on the suction side 29 and the discharge side 30. When the inner wall of the outer cylinder 24 is divided into left and right with the piston stop O as a boundary, the left side with the lateral grooves P and R becomes the suction side and the right side with the lateral grooves Q and S becomes the discharge side.

  From here, it demonstrates from the combination of the middle cylinder 25 and the outer cylinder 24 with FIG. 4, FIG. The five horizontal holes Ia at the position I of the middle cylinder 25 are opposed to the arc-shaped horizontal grooves P of the outer cylinder 24. The five horizontal holes Ja at the position J of the middle cylinder 25 are opposed to the arc-shaped horizontal grooves Q of the outer cylinder 24. Five horizontal holes Ka at the position K of the middle cylinder 25 are opposed to the arc-shaped horizontal grooves R of the outer cylinder 24. Five horizontal holes La at the position L of the middle cylinder 25 are opposed to the arc-shaped horizontal grooves S of the outer cylinder 24. The suction-side and discharge-side hydraulic devices are each provided with a hydraulic pump and an electromagnetic hydraulic switching valve (not shown in each drawing). Ports 6, 7, 8, 9 are formed by penetrating the holes from the four circular arc-shaped lateral grooves P, Q, R, and S provided on the left and right inner walls of the outer cylinder 24 to the outer wall of the outer cylinder 24. Called. The ports 6, 7, 8 and 9 are installed with piping from the port of the electrohydraulic switching valve (not shown in each drawing), and during normal rotation operation, the high pressure side is connected to the ports 7 and 9 and the low pressure side is connected to the ports 6 and 8.

  As described above, during the forward rotation operation in which the hydraulic cylinder rod 18 of the hydraulic cylinder 17 moves backward on the suction side 29 and moves forward on the discharge side 30 to convey the concrete, the outer cylinder 24 of the swivel-type hydraulic switching valve 23 as described above. The port 9 on the outer wall, the lateral groove P, the hole Ia of the middle cylinder 25 and the front of the hydraulic cylinder 17 communicate with each other, and pressure oil is conveyed from the high-pressure port 9 to the front of each hydraulic cylinder 17. The port 8, the lateral groove R, the hole Ka of the middle cylinder 25 and the rear of each hydraulic cylinder 17 communicate with each other. The port 8 is at a low pressure, and the low pressure oil fed from the rear of the hydraulic cylinder 17 is returned to the tank. Each hydraulic cylinder rod 18 of each hydraulic cylinder 17 that has rotated to the side always moves backward. The port 6 on the outer wall of the outer cylinder 24 of the swivel-type hydraulic switching valve 23, the lateral groove Q, the hole Ja of the middle cylinder 25, and the front of the hydraulic cylinder 17 communicate with each other. Return the oil to the tank. Each of the hydraulic pressures rotating to the discharge side is communicated with the port 7, the lateral groove S, the hole La of the middle cylinder 25, and the rear of the hydraulic cylinder 17, and conveys the pressure oil from the high-pressure port 7 to the rear of the hydraulic cylinder 17. Each hydraulic cylinder rod 18 of the cylinder 17 always moves forward.

  Note that the retracting range of the hydraulic cylinder rod 18 by the rotation of the drum 14 on the suction side 29 is determined by the length of the lateral grooves P and R provided on the inner wall of the outer cylinder 24. Similarly, the forward operation range by the rotation of the drum 14 of the hydraulic cylinder rod 18 on the discharge side 30 is determined by the lengths of the lateral grooves Q and S provided on the inner wall of the outer cylinder 24. That is, while the drum rotates and faces the lateral grooves P, R, Q, S provided on the inner wall of the outer cylinder 24 among the holes Ia, Ka, Ja, La of the middle cylinder 25 that rotates in the same manner as the drum. Accordingly, the hydraulic cylinder rod 18 of the hydraulic cylinder 17 communicating with the hole moves forward or backward and repeats reciprocating reciprocating motions on the suction side 29 and the discharge side 30. However, the hydraulic pressure communicated with each hole Ia, Ka, Ja, La of the middle cylinder 25 that has been turned to the piston stop region O located between the lateral grooves P, R and Q, S provided on the inner wall of the outer cylinder 24. The cylinder 17 stops the reciprocating motion of the hydraulic cylinder rod 18 because the conveyance of the pressure oil from the ports 9, 8, 6, and 7 and the return of the tank of the low pressure oil are stopped.

  On the other hand, at the time of reverse operation in which the hydraulic cylinder rod 18 advances on the suction side 29 and the hydraulic cylinder rod 18 on the discharge side moves backward, the electromagnetic hydraulic switching valves of the suction side 29, the discharge side 30 and the swing motor (not shown in each figure). When the description 14) is switched to reverse rotation, the drum 14 rotates in the opposite direction and the drum rotates to suck the fluid from the discharge side and discharge the fluid sucked on the discharge side to the suction side. In the present invention, each hole of the inner cylinder 25 is divided into four stages Ia, Ja, Ka, and La in consideration of the internal leakage of the hydraulic oil on the contact surface between the inner cylinder 25 and the outer cylinder 24. , Q, R, and S have been described in four stages, but each hole in the inner cylinder 25 and the inner wall arc-shaped lateral groove on the outer cylinder 24 have the same function even if they have a two-stage structure. A hydraulic motor 19 is fitted and fixed to the center shaft of the drum 14 and serves as a driving source for the drum 14.

  The fluid transport device of the present invention is used for transporting concrete safely and efficiently at a construction site, but it can also be used for transporting a fluid with high clay content including coarse particles other than concrete as well as other liquids. it can.

14 Drum 15 Concrete cylinder 16 Concrete piston 17 Hydraulic cylinder 18 Hydraulic cylinder rod 19 Hydraulic motor 20 Partition board 21 Valve case 23 Swivel hydraulic switching valve 24 Swivel hydraulic switching valve outer cylinder 25 Swivel hydraulic switching valve inner cylinder 26 Face plate 27 Horizontal outer cylinder 28 Discharge case 29 Suction side 30 Discharge side P, R Swivel hydraulic switching valve inner wall left lateral groove Q, S Swivel hydraulic switching valve outer cylinder inner wall right lateral groove I, J, K, L Swivel Each stage Ia on the side surface of the intermediate cylinder of the hydraulic pressure switching valve Five holes Ja of the I stage of the intermediate cylinder of the swivel hydraulic switching valve J Five holes of the J stage of the intermediate cylinder of the swivel hydraulic switching valve Ka K-stage 5 holes La Swivel hydraulic switching valve L-stage 5 holes O Piston stop

Claims (2)

It is a device that pumps fluids with high viscosity and coarse particle size such as concrete, and a plurality of reciprocating pumps composed of concrete cylinders, concrete pistons and hydraulic cylinders are arranged in parallel on a rotating drum on a concentric circle around the center axis. In the fluid pressure feeding device, a face plate provided at one end in the longitudinal direction of the drum and having an opening communicating with the concrete cylinder of each of the reciprocating pumps, and a mechanism for detecting the rotation of the drum and switching the hydraulic pressure of the hydraulic cylinder A valve mechanism that covers the opening of the face plate in a boundary region between the suction side and the discharge side, the valve mechanism comprising a partition board built in a valve case provided between the suction side and the discharge side. The panel is in contact with the rotating face plate and completely covers the face plate opening. Prevents the flowing into et suction side, the flow transfer apparatus that contact state is characterized by being held between the face plate by a pressing mechanism The fluid pressure feeding device according to claim 1, wherein the partition plate itself built in the valve case is rotated.

Images