JPS60201084A - Pump for concrete - Google Patents

Abstract

PURPOSE:To eliminate necessity to use a valve in order to reduce the consumption of components and decrease the pulsation of the pump by employing a swash plate type axial plunger pump as the pump for concrete. CONSTITUTION:A cylinder block 5, equipped with a multitude of cylinders 3, is supported pivotally by a shaft 6. A gear 7 is formed on the outer periphery of the cylinder block 5. The block is located so that a cylinder under a suction stroke is opened at the suction port 33a of a hopper 33 for concrete. A piston 30 is connected to the swash plate 2. The swash plate 2 is supprted rotatably by a guide plate 15 and is provided with the gear 17. A counter gear 9 is driven by a hydraulic motor 12. The counter gear 9 pivots the cylinder block 5. The swash plate 2 is rotated by a counter shaft 10 through a joint 20 synchronously with the cylinder block 5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a concrete pump, and particularly to a concrete pump used in a concrete pump truck.

Conventionally, concrete pumps consist of two hydraulic cylinder devices, two reciprocating pumps driven by the hydraulic cylinder devices, and a slide valve that switches the pump's discharge/intake passage. In the pump suction stroke, concrete is sucked into the pump cylinder from the hopper, and in the pump discharge stroke, the concrete in the cylinder is discharged into the discharge pipe, and the concrete 1 is removed from the hose that is being moved to a predetermined position by the boom mechanism. It was being pressure-fed and poured. For this reason, the slide valve repeatedly slides during each discharge and suction stroke under high pressure, which causes wear and tear and requires early replacement, making maintenance cumbersome and limiting operating time. . Furthermore, the tightness of the valve is poor, which inevitably causes pressure leaks, so when there is less concrete in the hopper, concrete rebounds, requiring the operator to constantly pay attention to the hopper, and the mixer that feeds the concrete into the hopper. Concrete may bounce back onto cars, causing accidents. Also, since it is not possible to send out every last drop of concrete, problems may occur at the dumping site for the remaining concrete, and furthermore, the pump cylinder Concrete adheres to and remains on the cylinders and piping, making cleaning of these cylinders and piping extremely troublesome, and these factors combined to significantly reduce work efficiency.

In addition, because two pumps are used for pressure feeding, large pulsations occur in the discharge pressure, and the transportation piping and hoses vibrate violently back and forth, leading to large wear and tear on parts and damage to concrete-placed areas. In addition, due to leakage from the valve, it is not possible to send water using a concrete pump, which necessitates installing a separate water pump, which increases costs. The trend is to increase the cylinder diameter, lengthen the piston stroke, and increase the speed of the piston, leading to greater wear and tear on parts, increased fuel consumption, and further increased costs.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a concrete pump that eliminates the above-mentioned drawbacks by eliminating the valve from the concrete pump, separating the suction section and the discharge section, and discharging continuously. It is.

The present invention applies the swash plate type axial plunger pump type to a pump for concrete, and rotates a cylinder block having a large number of cylinders and a rotating swash plate tilted at a predetermined angle by a gear formed on the outer periphery. In addition, the block head fixed to the base includes a suction section that opens into a cylinder corresponding to the suction stroke and communicates with the suction port at the bottom of the hopper, and a discharge section that opens into a cylinder corresponding to the discharge stroke and communicates with the delivery side piping. Based on the synchronized rotation of the cylinder block and rotating swash plate, the concrete in the hopper is sucked into the cylinder via the suction part, and the concrete in the cylinder is further discharged to the delivery side piping via the discharge part. There is a pump for concrete that is characterized by:

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, this concrete pump 1 is a swash plate type axial piston pump type, which includes a rotating swash plate 2 inclined at a predetermined angle and a large number (six) of cylinders 3 and 3.
It has a cylinder block 5 equipped with... Further, the cylinder block 5 is rotatably supported by a cylinder block shaft 6 (see FIG. 4), and a gear 7 is formed around it. Further, adjacent to the cylinder block 5, a counter gear 9 is connected to a counter shaft 10 and a bearing 11.
The gear 9 meshes with the gear 7 and also meshes with a drive gear 13 fixed to the output shaft of the hydraulic motor 12.

On the other hand, the rotating swash plate 2 is rotatably supported by the guide plate 15 via a bearing 16, and a gear 17 having the same number of teeth as the gear 7 is mounted on the opposite side of the guide plate 15.
is fixed by a fixing screw 19 (see FIG. 5).

Further, a shaft 21 is connected to the tip of the counter shaft 10 via a universal gear 20 which is extendable and retractable by a spline, and the shaft 21 has a counter having the same number of teeth as the counter gear 9. A gear 25 is fixed, the gear 25 meshes with the gear 17, and
The tip of the shaft 21 is rotatably supported by a bearing 11 fixed to the guide plate 5 via a bracket 15a. Further, the guide plate 15 is swingably supported by a pivot shaft 26 disposed adjacent to the joint 20 (see FIG. 3), and a discharge amount is provided on the opposite side of the pivot shaft 26. An adjustment hydraulic cylinder device 27 is connected.

A rod 29 is connected to the rotating swash plate 2 via a pole joint portion 29a, and a piston 30 located within the cylinder 3 is connected to the other end of the rod 29.

Further, the pump 1, as shown in FIGS. 1 to 4,
It has a base 31 which is fixedly fixed to the concrete pump body, and a cylinder block shaft 6 is rotatably supported on the base 31 via a bearing 11, and faces the side end surface of the cylinder block 5. A block head 32 and a hopper 33 are fixed or formed integrally. The block head 32 is formed with a suction part 35 and a discharge part 36, each of which is an arcuate concave groove. The discharge portion 36 is open to the cylinder 3 corresponding to the discharge stroke and communicated with the delivery side piping 37. In addition, hopper 33
A stirring shaft 40 having a large number of stirring blades 39 is rotatably supported therein, and a stirring gear 41 is fixed to one end of the stirring shaft 40, and the gear 41 is connected to a stirring hydraulic motor 4.
2 through a chain 43.

Further, a seal 45 made of urethane or the like is interposed between the block head 32 and the cylinder block 5, and the seal 45 has an arcuate opening formed to correspond to the suction section 35 and the discharge section 36. In addition, as shown in detail in FIG. 6, there is an annular convex portion 45a that is fitted and fixed to the block head 32, and a recess 4 that is formed toward the opening.
5b, and grease nipples 46 are installed at predetermined intervals on the annular convex portion 45a, and grease is supplied to the sliding surface between the seal 45 and the block 5.

In addition, in FIG. 1, 47 is a hydraulic pump that drives the hydraulic motors 12, 42 and the hydraulic cylinder device 27, 49 is a control box that controls these, 50 is an oil tank, 5
1 is a hydraulic pipe, and 52 is a drive shaft for driving the hydraulic pump 47, which is connected to the engine of the concrete pump vehicle. In addition, in FIG. 3, 53 is the base 31
This is a bearing that is fixed to and rotatably supports the pivot shaft 26.

Since this embodiment has the above-described configuration, when the hydraulic pump 47 is rotated based on the rotation of the engine, the hydraulic motor 12 and the stirring hydraulic motor 42 are rotated via the control box 49. As a result, the stirring shaft 40 is rotated via the chain 43 and the stirring gear 41 to stir the concrete in the hopper 33 supplied from the mixer truck, and the cylinder block is rotated via the drive gear 13, counter gear 9, and gear 7. 5 and rotate the axis 10°24
, the rotating swash plate 2 rotates in synchronization with the cylinder block 5 via the counter gear 25 and the gear 17. As a result, the cylinder block 5 and the rotating swash plate 2 rotate almost integrally, but since the rotating swash plate 2 rotates on an inclined plane based on the predetermined inclination angle of the guide plate 15, the block 5 and the rotating swash plate The distance between the rod 29 changes and the distance between the rod 29 and the rod 29 changes.
The piston 30 moves to the right in FIG. 3 is in communication with the suction port 33a of the hopper 33 through the opening of the seal 45 and the suction portion 35 of the block head 32, and the concrete in the hopper 33 is sucked into the cylinder 3, and the concrete is further sucked into the cylinder 3.

When the cylinder block 5 rotates and reaches the discharge part while inhaling the gas, the cylinder 3 communicates with the discharge part 36 of the head 32 through the opening of the seal 45, and the rotation of the rotating swash plate 2 and the cylinder block 5 causes the cylinder block 5 to rotate and reach the discharge part. Due to the movement of the piston 30 in the discharge direction, the concrete in the cylinder 3 is transferred to the discharge section 3.
Concrete is discharged to the delivery side piping 37 via the hose 6, and the concrete is forced to be poured and placed at a predetermined location by a hose that is moved to an appropriate position by a boom mechanism. At this time, a large force is applied to the pump 1 due to the pressure-feeding of concrete to a high place and a long distance, but the cylinder block 5 and rotating swash plate 2 rotate together, and drive is applied from the outer periphery by the gear 7.17. Moreover, since the rotating swash plate 2 is directly supported by the guide plate 15 via the bearing 16, the pump 1 has a sturdy structure that can withstand the above-mentioned large force. Furthermore, since a large number of cylinders 3 and screws 30 sequentially repeat suction and discharge while rotating, there is little change in pump pressure, that is, pulsation, and the suction portion 35 communicating with the hopper 33 always follows the suction stroke of the piston 30. Therefore, pump pressure will not leak into the hopper 33. Furthermore, when the control box 49 controls the expansion and contraction of the discharge amount adjusting hydraulic cylinder device 27, the angle of the guide plate 15 around the pivot 26, and therefore the rotation plane of the rotary swash plate 2, changes, changing the stroke of the piston. The discharge amount can be adjusted by That is, when the cylinder device 27 is extended, the stroke is shortened and the discharge amount is decreased, and when the cylinder device is contracted, the stroke is lengthened and the discharge amount is increased.

Note that the discharge amount can also be adjusted by adjusting the rotational speed of the hydraulic motor 12 using the control pock 49 without changing the inclination angle of the rotary swash plate 2. In this case, the guide plate 15 is oscillated. It may be fixed to the base 31 at a predetermined angle instead of being supported freely.

Furthermore, suction force is always acting on the suction port 33a at the bottom of the hopper, and the piston stroke is significantly shorter than that of conventional reciprocating pumps, so even if the concrete in the hopper 33 is low, The last drop is completely absorbed without rebounding. And hopper 3
When there is no more concrete in the cylinder 3, reach out from the hopper 33, fill the cylinder 3 with a cylindrical sponge, and then fill the hopper 33 with water. At this time, the end of the cylinder 3 is closed watertightly by the piston 30, and the suction part 35 and the discharge part 36 are completely separated by the seal 45, so the water in the hopper 33 does not leak and is sufficiently can be stored in

In this state, when the hydraulic motor 12 is rotated to drive the pump 1 again, the sponge follows the piston 30 and slides inside the cylinder 3, scraping off the concrete adhering to the cylinder wall, and furthermore, along with the water. \Discharge part 36 of Rad 32
It passes through and is discharged to the delivery side piping 37. Next, the water in the hopper 33 is sucked in from the suction port 33a based on the suction stroke of the piston 30, and is discharged to the discharge part 36 based on the discharge stroke of the piston 30, whereby the inner walls of the cylinder 3 and the suction part 35/discharge part 36 are It is discharged from the delivery side piping 37 and the tip hose, and together with the previous sponge, it also cleans the piping 37 and the hose.

Note that in the above embodiment, the hydraulic pump 47 and the hydraulic motor 1
Although the pump 1 and stirring shaft 40 are driven through the shafts 2 and 42, they may be driven directly from the engine through the shafts.

As explained above, according to the present invention, since the valve is eliminated from the concrete pump 1, there is no need to replace the valve, which was necessary in the past, and maintenance becomes easy.
Operation time can be extended. Moreover, since the suction part 35 and the discharge part 36 are completely separated, suction force is always applied to the suction port 33a of the hopper 33, and even if there is less concrete in the hopper 33, rebound of the concrete is prevented. The work can be carried out safely and easily.Furthermore, the concrete and cleat in the hopper 33 can be delivered to the last drop, eliminating waste of concrete and removing the remaining concrete from the hopper 33. , the cylinder 3 and the piping can be cleaned extremely easily, work efficiency can be greatly improved, and the water pump that was conventionally required can be eliminated. In addition, since a large number of cylinders 3 discharge continuously based on the rotation of the cylinder block 5, pulsations in the discharge pressure are significantly reduced, eliminating back-and-forth vibration of pipes and hoses, and preventing damage to concrete placement locations. It can be eliminated.

Furthermore, although the concrete pump 1 is an application of the swash plate type axial plunger pump type, it can have a sturdy structure, and is designed for use with hard and heavy objects such as concrete, which require high discharge pressure. Since there are a large number of cylinders 3, it can be used for concrete pumps such as concrete pumps without increasing the cylinder diameter and the piston stroke.
The amount of pumping can be dramatically increased, and since it requires only one rotation of the cylinder head 5 and rotating swash plate 217), the amount of hydraulic oil can be significantly reduced, and fuel consumption can also be reduced. be able to.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional plan view showing a concrete pump according to the present invention, FIG. 2 is a left side view thereof, FIG. 3 is a right side view thereof, and FIG. 4 is a partially sectional front view, FIG. 5 is a sectional view showing the rotary swash plate portion, and FIG. 6 is a sectional view showing the seal portion. 1. Concrete pump, 2. Rotating swash plate
, 3 ・Cylinder , 5 ・ Cylinder block ,
7...Gear, 17...Gear, 291.0 Tsudo,
3o: Piston, 31: Base, 32: Block head, 33: Hopper, 33a: Suction port, 35: Suction part, 36: Discharge part,
37... Outlet side piping applicant: Co., Ltd. 8 Commerce, Figure 3, 26 26 Figure 4, Figure 5, Figure 6 I

Claims (1)

[Claims] (1) A cylinder block having a large number of cylinders, a rotating swash plate that rotates on a surface inclined at a predetermined angle with respect to the rotation plane of the cylinder block, and a rotating swash plate located facing the side end surface of the cylinder block and fixed to a base. The block head is equipped with a gear on the outer periphery of the cylinder block and rotating swash plate, and the piston sliding in the cylinder and the rotating swash plate are connected via a rod. A suction section that opens into the corresponding cylinder and communicates with the suction port at the bottom of the hopper, and a discharge section that opens into the cylinder corresponding to the discharge stroke and communicates with the delivery side piping, are arranged so that the cylinder block and rotation angle are controlled by the gear. A concrete pump that rotates plates synchronously, sucks concrete in a hopper into a cylinder through a suction part, and then discharges the concrete in the cylinder to a delivery pipe through a discharge part.