JPH1030555A - Oscillating pipe jumping-up depressurization device for oscillating valve type concrete pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To operate a clutch smoothly at the time of jumping-up an oscillating pipe. SOLUTION: An accumulator 26 and an oscillating switching valve 27 are fitted on a pressure oil line 24 for oscillating cylinders 14, 15 in order from the upstream side. A pilot check valve 44 is fitted at a more downstream position than the accumulator 26 of the pressure oil line 24. A depressurization line 46 which communicates with a tank 19 is connected at a more downstream position than the pilot check valve 44 of the pressure oil line 24 through a depressurization electromagnetic switching valve 47. A shutdown pilot line 48 which makes pilot pressure work upon the pilot check valve 44 is connected at an auxiliary line 45 connected to the pressure oil line 24 through the switching valve 47.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swing cylinder which swings a swing tube to the left and right when a swing tube serving as a suction and discharge valve housed in a concrete hopper is flipped up and washed. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure relief device for rocking a rocking pipe of a rocking valve type concrete pump used for releasing pressure.

[0002]

2. Description of the Related Art Concrete pumps in which concrete in a hopper is alternately sucked and discharged by two concrete pumping cylinders are provided with a slide valve type as a suction and discharge valve for switching suction and discharge. A type employing a swing valve type is conventionally known.

As shown in FIGS. 3 and 4, a conventional concrete pump in which a suction / discharge valve is a swing valve is used.
At the lower portion of the front side wall 1a of the hopper, two suction / discharge ports 2 are provided side by side, and two concrete pressure feeding cylinders 3 and 4 communicating with the two suction / discharge ports 2 are provided outside the hopper 1.
Are installed in parallel with each other,
The concrete pumping piston 5 housed in the concrete hydraulic pumping cylinder 4 is connected to the main hydraulic pistons 9 in the main hydraulic cylinders 7, 8 connected to the concrete pumping cylinders 3, 4 via a washing chamber via one rod 10. The concrete hydraulic pistons 5 in the main hydraulic cylinders 7 and 8 are alternately advanced and retracted by being integrally connected, so that the concrete pressure feeding pistons 5 are alternately advanced and retracted. In the hopper 1,
Positioning the oscillating tube 11 bent in an S-shape,
A valve ring 12a is attached to the front end of the hopper 1 so that the valve ring 12a can alternately coincide with the two suction / discharge ports 2 via a valve plate 12b attached to the inner surface of the front side wall 1a of the hopper 1. Swing tube 1
The two oscillating cylinders 1 each having an end connected to a transport pipe through the rear wall 1b of the hopper 1 and having a connecting shaft 13 fixed in the middle of the oscillating pipe 11 installed outside the hopper 1.
The swing tube 11 can be swung in the left-right direction about the connecting shaft 13 by connecting the swing lever 11 to the left and right via the operation lever 16 and tilting the operation lever 16 right and left. In FIGS. 3 and 4, reference numeral 1c denotes a step portion provided on both the left and right sides of the hopper 1, and 6 denotes a stirring blade for flowing the concrete 17 of the step portion 1c downward while stirring.

In the above-mentioned swinging valve type concrete pump, when the work of feeding the concrete 17 is completed, the swinging pipe 11 is rotated.
Although it is necessary to remove the concrete 17 remaining in the concrete, the concrete 1 can be removed with a simple operation in a short time.
A cleaning method has been proposed in which the concrete 7 can be removed and washed, and the concrete 17 to be removed is not scattered around.

FIG. 5 shows an example of this. An opening 34 slightly larger than the diameter of the oscillating tube 11 is provided above the front side wall 1a of the hopper 1 and at the position of the oscillating radius of the oscillating tube 11. ,
A cleaning pipe 35 is attached to the opening 34 so that the opening 34 is always closed to prevent the concrete 17 in the hopper 1 from flowing out. On the other hand, the front position of the front side wall 1a of the hopper 1 is set. A jumping motor 37 provided with a driving sprocket 36 on the output shaft is provided on one of the lateral sides of the connecting shaft 13 projecting forward through the front side wall 1a as a jumping drive device. At the same time, the driven sprocket 38 is rotatably attached to the foremost portion of the connection shaft 13 so that the rotational force of the jumping motor 37 is transmitted from the driving sprocket 36 to the driven sprocket 38 via the chain 39, In addition, the driven sprocket 38 and the connection shaft 13 are integrally connected between the driven sprocket 38 and the operation lever 16, or connected to the operation lever 16. 13 or integrally connected to,
A clutch 40 for switching transmission of the rotational force of the jumping motor 37 to the connection shaft 13 and the transmission of the oscillating power by the operation lever 16 is provided.
A clutch engaging / disengaging cylinder 41 is provided on the opposite side of the connecting shaft 13 protruding forward from the motor installation side to the clutch installing / disengaging cylinder 41, and after the concrete 17 pressure feeding operation is completed, the clutch engaging / disengaging cylinder 41 is extended. By letting
The clutch 40 is moved to integrate the driven sprocket 38 with the connecting shaft 13, and then the jumping motor 37 is driven, so that the rotational force of the motor 37 is transmitted from the driving sprocket 36 through the chain 39 and the driven sprocket 38. When the swing tube 11 is pivoted so as to jump upward by transmitting it to the connection shaft 13 so that the front end communicates with the opening 34, and when the front end of the swing tube 11 communicates with the opening 34, an elbow shape is obtained. The cleaning pipe 35 thus connected is pressed from the outside of the hopper 1 and connected to the swinging pipe 11 through the opening 34 by the operation of the cleaning pipe moving cylinder 42, the filling 43 is put into the cleaning pipe 35, and the filling 43 is shaken with the high-pressure fluid. By moving the inside of the moving tube 11 and the inside of the transport tube, the inside of the oscillating tube 11 and the inside of the transport tube is cleaned.

[0006]

However, in the case of the recently proposed swing valve type concrete pump as shown in FIG. 5, switching between the normal casting and the swinging up of the swing pipe 11 for washing is performed. The operation is performed by engaging and disengaging the clutch 40. At this time, the oscillating tube 1 is
Since the swinging tube 11 is caused to jump up while the swinging cylinder 1 is swung to one side, pressure acts on the swinging cylinders 14 and 15, and the pressure is transmitted from the operation lever 16 to the clutch 40. Therefore, there is a problem that the biasing force around the connection shaft 13 acts on the clutch 40, and the operation of the clutch 40 cannot be performed smoothly.

Accordingly, the present invention is intended to prevent the biasing force around the connecting shaft from acting on the clutch when the swing tube is flipped up, so that the clutch can be smoothly engaged and disengaged. What you want to do.

[0008]

According to the present invention, in order to solve the above-mentioned problem, a swing pipe in a hopper is swung right and left so as to be alternately coincident with two suction / discharge ports at a lower portion of a front wall of the hopper. In the pressure oil line to the swing cylinder, an accumulator and a swing switching valve are provided in order from the upstream side, and a pilot check valve is installed at a position downstream of the accumulator of the pressure oil line toward the swing switching valve side. An electromagnetic switching valve for pressure release is provided between a pressure release line connected to a position downstream of the pilot check valve of the pressure oil line and an auxiliary line connected to a position upstream of the accumulator of the pressure oil line. Further, a pilot line for shut-off is connected between the solenoid valve for depressurizing and the pilot check valve, and the solenoid-operated switching valve for depressurizing is moved to a depressurizing position by a switch for jumping up the swinging pipe. And the configuration can be switched on.

When the pressure-releasing electromagnetic switching valve is switched to the pressure-releasing position by the jumping-up switch, the pilot pressure acts on the pilot check valve through the auxiliary line and the shutoff pilot line, and the pilot check valve is shut off. Therefore, the supply of the pressure oil from the accumulator is shut off. At this time, the pressure release line and the tank communicate with each other via the pressure release electromagnetic switching valve, so that the pressure of the swing cylinder is released.

A pressure oil line to a oscillating cylinder for oscillating the oscillating pipe in the hopper to the left and right so as to alternately coincide with the two suction / discharge ports at the lower portion of the front wall of the hopper is provided in order from the upstream side. An accumulator and a swing switching valve as a three-position valve that is switched by operation of an electromagnetic switching valve are provided, so that the electromagnetic switching valve is demagnetized by a switch for swinging up the swing pipe so that the swing switching valve is switched to a neutral position. In such a configuration, when the electromagnetic switching valve is demagnetized, the swing switching valve is switched to the neutral position, so that the pressure of the swing cylinder is released.

[0011]

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

FIG. 1 shows an embodiment of the present invention. In an oscillating valve type concrete pump having a structure similar to that shown in FIG. 5, pressure oil discharged from an oil pump 23 is oscillated by an oscillating cylinder 14. Oil line 2 to supply to, 15
4, an unload valve 25, an accumulator 26, and a swing switching valve 27 are provided in this order from the upstream side, and the pressure oil is supplied to the swing switching valve 27 side at a position downstream of the accumulator 26 of the pressure oil line 24. A pilot check valve 44 is provided so as to allow the pressure to flow, and a pressure release line 46 connected to the pressure oil line 24 at a position downstream of the pilot check valve 44 and an auxiliary line 45 connected to a position upstream of the accumulator 26. An electromagnetic switching valve 47 for depressurization is provided in between, and a pilot line 48 for disconnection is connected between the electromagnetic switching valve 47 for depressurization and the pilot check valve 44, and a jumping switch (not shown) is turned on. When the pressure in the accumulator 26 is cut off by switching the port a from the port a to the port b as excitation when the pressure release electromagnetic switching valve 47 is Sometimes it can disconnect the pressure swing cylinder 14, 15 to the tank 19.

In the above concrete pump,
Two main hydraulic cylinders 7, 8 and two swing cylinders 1
An example of a hydraulic circuit for operating the valves 4 and 15 at required timing is as follows. That is, the oil pump 1
A main switching valve 21 is provided in the middle of a pressurized oil supply / discharge line 20 connecting the tank 8 and the tank 19 with the head-side pressure chambers of the two main hydraulic cylinders 7, 8. The rod-side pressure chambers are connected to each other by a sealing circuit 22, and the switching of the main switching valve 21 causes the pressure oil discharged from the main oil pump 18 to be alternately supplied to the head-side pressure chambers of the main hydraulic cylinders 7 and 8, so that The main hydraulic piston 9 in the hydraulic cylinder 7 and the main hydraulic piston 9 in the main hydraulic cylinder 8 are alternately moved forward and backward, so that the two concrete pressure feeding cylinders 3 and 4 alternately switch between the suction side and the discharge side. The concrete 17 in the hopper 1 is sucked and discharged.

A boost valve 29 and a boost valve 29 are provided in the middle of a pilot line 28 connecting the position of the pressure oil line 24 downstream of the accumulator 26 and the switching operation section of the main switching valve 21.
A reversing valve 33a is provided, and branch pilot lines 30a and 30b branched from a position downstream of the boost valve 29 of the pilot line 28 are connected to a switching operation section of the swing switching valve 27. The other pilot line 31 taken out from the middle of the main hydraulic cylinder 7 or 8 is guided to the switching operation section of the boost valve 29 via the pilot switching valve 32 for the main hydraulic cylinders 7 and 8 and the reversing valve 33b. When the main hydraulic piston 9 moves forward to the stroke end, the pilot switching valve 32 is switched by the main hydraulic piston 9 and the boost valve 29 is switched by the pilot pressure.

When the swinging pipe 11 is flipped up for washing after the concrete pumping operation is completed, the rocking cylinders 14 and 15 are operated to move the rocking pipe 11 to the flipping-up side and fix it. After that, the jumping-up switch is turned ON to switch the pressure release electromagnetic switching valve 47 from the port a to the port b, and then the clutch on / off cylinder 41 in FIG. 5 is extended.

In this case, when the depressing electromagnetic switching valve 47 is switched to the port b by the jumping-up switch ON, the pressure oil discharged from the oil pump 23 is changed from the pressure oil line 24 to the auxiliary line 45, and the depressing electromagnetic switching is performed. Acting on the pilot check valve 44 through the valve 47 and the pilot line 48 and closing the pilot check valve 44, the pressure of the accumulator 26 is cut off by the pilot check valve 44. On the other hand, since the pressure release line 46 is communicated with the tank 19 via the pressure release electromagnetic switching valve 47, the pressure acting on the swing cylinders 14 and 15 is reduced by the pressure oil line 24 and the pressure release line 46. , To the tank 19 via the pressure switching electromagnetic switching valve 47.

As a result, the force transmitted from the operation lever 16 to the clutch 40 disappears, and the biasing force around the connecting shaft 13 does not act on the clutch 40, so that the clutch 40 can be operated smoothly. The swing tube 13 can be reliably flipped up.

FIG. 2 shows another embodiment of the present invention, in which the present invention is applied to an oscillating valve type concrete pump in which an oscillating switching valve is switched by operating an electromagnetic switching valve. It shows about.

That is, an unload valve 25, an accumulator 26, and a swing switching valve 27 'are provided in the pressure oil line 24 for supplying pressure oil to the swing cylinders 14, 15 in this order from the upstream side. In the configuration in which the switching operation of the swing switching valve 27 'is performed by switching the solenoid switching valve 27' by a pilot pressure based on the switching of the electromagnetic switching valve 49, the swing switching valve 27 'is turned on. The solenoid-operated switching valve 49 is demagnetized when it is turned on.

In the configuration shown in FIG. 2, when the switch for jumping is turned on, the electromagnetic switching valve 49 is demagnetized, so that the pilot pressure does not act on the swing switching valve 27 '. Since the swing switching valve 27 'is switched to the neutral position, the pressure of the swing cylinders 14, 15 can be released to the tank 19 via the swing switching valve 27'. Therefore, the clutch in FIG. 5 can be operated smoothly.

[0021]

As described above, according to the depressurizing device for jumping the swinging pipe of the swinging valve type concrete pump of the present invention, the following excellent effects are exhibited. (1) A hydraulic oil line to a rocking cylinder that rocks the rocking pipe in the hopper to the left and right so as to alternately coincide with the two suction and discharge ports at the lower portion of the front wall of the hopper. A swing switching valve is provided, a pilot check valve is installed at a position downstream of the accumulator of the pressure oil line toward the swing switching valve side, and a pressure is connected to a position downstream of the pilot check valve of the pressure oil line. An electromagnetic switching valve for depressurizing is provided between the depressurizing line and an auxiliary line connected to a position upstream of the accumulator of the pressure oil line, and further, a solenoid valve for depressurizing is provided between the electromagnetic switching valve for depressurizing and the pilot check valve. The shutoff pilot line is connected, and the pressure release solenoid switching valve can be switched to the pressure release position by the rocking tube lifting switch. When the pressure-switching electromagnetic switching valve is switched to the pressure-releasing position during the pressure operation, the pressure acting on the swing cylinder is released from the pressure oil line via the pressure-releasing line and the pressure-releasing electromagnetic switching valve. As a result, the clutch can be operated smoothly without applying a biasing force around the connecting shaft to the clutch, and the rocking tube can be reliably flipped up, and the reliability of the machine can be improved. Can be enhanced. (2) A hydraulic oil line to a oscillating cylinder for oscillating the oscillating pipe in the hopper to the left and right so as to alternately coincide with the two suction / discharge ports at the lower portion of the front wall of the hopper. A swing switching valve is provided as a three-position valve that can be switched by operation of the solenoid switching valve, and the solenoid switching valve is demagnetized by the switch for swinging the swing pipe so that the swing switching valve is switched to the neutral position. Thus, when the swing tube is flipped up, when the electromagnetic switching valve is demagnetized and the swing switching valve is switched to the neutral position, the pressure acting on the swing cylinder is changed via the electromagnetic switching valve. Since the clutch can be disengaged, the force on the clutch can be released, and the clutch can be operated smoothly.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of a pressure relief device for popping up a swing pipe of a swing valve type concrete pump according to the present invention.

FIG. 2 is a schematic diagram showing another embodiment of the present invention.

FIG. 3 is a schematic view showing an example of a swing valve type concrete pump.

FIG. 4 is a view taken in the direction of arrows IV-IV in FIG. 3;

FIG. 5 is a schematic view showing a recently proposed rocking tube cleaning method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hopper 1a Front wall 2 Suction / discharge port 11 Oscillating pipe 14 Oscillating cylinder 15 Oscillating cylinder 24 Pressure oil line 26 Accumulator 27 Oscillating switching valve 27 'Oscillating switching valve 44 Pilot check valve 45 Auxiliary line 46 Depressurizing line 47 Solenoid switching valve for pressure release 48 Pilot line for shutoff 49 Solenoid switching valve

Claims (2)

[Claims] 1. A pressure oil line to a swing cylinder which swings a swing pipe in a hopper to the left and right so as to alternately coincide with two suction / discharge ports at a lower portion of a front wall of the hopper. An accumulator and a swing switching valve are provided, and a pilot check valve is installed at a position downstream of the accumulator of the pressure oil line toward the swing switching valve and connected to a position downstream of the pilot check valve of the pressure oil line. A pressure release electromagnetic switching valve is provided between the pressure relief line and the auxiliary line connected to the pressure oil line at a position upstream of the accumulator, and the pressure relief electromagnetic switching valve and the pilot check valve are connected to each other. A shutoff pilot line is connected therebetween, and the pressure release solenoid switching valve is configured to be switched to a pressure release position by a switch for swinging up the swinging pipe. Depressurizing device for rocking valve jump of rocking valve type concrete pump. 2. A pressure oil line to a swing cylinder for swinging a swing pipe in a hopper left and right so as to alternately match two suction and discharge ports at a lower portion of a front wall of the hopper. An accumulator and a swing switching valve as a three-position valve that is switched by operation of an electromagnetic switching valve are provided, so that the electromagnetic switching valve is demagnetized by a switch for swinging up the swing pipe so that the swing switching valve is switched to a neutral position. Pressure relief device for oscillating pipe jumping of oscillating valve type concrete pump having the above configuration.