JPH0412151Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an earth and sand pumping device for pumping excavated earth and sand using a piston, such as a shield excavator.

[Conventional technology]

The configuration of a conventional earth and sand pumping device is shown in Figures 5 and 6.
This will be explained with reference to the figures.

This conventional earth and sand pumping device has an earth and sand storage tank 1.
and a cylindrical slide tube 3 having an open end and sliding back and forth linearly within the sediment storage tank 1;
An earth and sand pumping piston 2 that reciprocates inside this slide cylinder 3 in the axial direction of the slide cylinder 3, a ring-shaped seal 4 provided at a place where the tip of the slide cylinder 3 of the earth and sand storage tank 1 comes into contact, and the earth and sand The storage tank 1 is provided with a pressure feeding pipe 5 connected to the storage tank 1. The sediment storage tank 1 is integrally provided with a cylindrical seal case 6 that holds a seal 4. The slide tube 3 is reciprocated by a slide tube jack 8. In addition, the earth and sand pumping piston 2
is configured to be reciprocated by a piston jack 7, and has a flange 9 integrally formed at its base end with which the base end of the slide tube 3 engages. The seal 4 is made of metal or urethane rubber, and has a structure in which the slide tube 3 is pressed against the seal 4 to achieve sealing.

Next, the operation of the conventional earth and sand pumping device described above will be explained in the fifth section.
This will be explained with reference to the figures.

(a) Extend the slide cylinder jack 8, slide the slide cylinder 3 in the direction of the arrow, and take the earth and sand 10 in the earth and sand storage tank 1 into the slide cylinder 3.

(b) Further extend the slide cylinder jack 8 and press the tip of the slide cylinder 3 against the seal 4 to seal and isolate the inside of the slide cylinder 3 and the inside of the sediment storage tank 1.

(c) Extend the piston jack 7 and slide the earth and sand pumping stone 2 in the direction of the arrow to push out the earth and sand 10 inside the slide tube 3 and forcefully feed it into the pressure pipe 5.

(d) Retract the slide tube jack 8 and slide the slide tube 3 back in the direction of the arrow. At this time,
When the base end of the slide tube 3 engages with the flange 9 of the earth and sand pumping piston 2, the earth and sand pumping piston 2 also slides back in the direction of the arrow along with the slide tube 3, and the earth and sand 10 is newly sucked into the earth and sand storage tank 1. It can be done.

Thereafter, the above-mentioned operations (a), (b), (c), and (d) are repeated to force-feed the earth and sand 10 through the pressure-feeding pipe 5.

In this type of earth and sand pumping equipment, the above-mentioned operation is
In step (b), it is important to reliably press the slide tube 3 against the seal 4 to completely isolate the inside of the slide tube 3 and the inside of the earth and sand storage tank 1 in order to forcefully transport the earth and sand 10.

[Problem that the invention attempts to solve]

In the above earth and sand pumping device, the earth and sand in the slide cylinder 3 is pumped by the earth and sand pumping piston 2 from a state in which the slide tube 3 is extended and the pressure pipe 5 and the sediment storage tank 1 are isolated (the state shown in FIG. 5B). While reaching the state of pushing out to the pipe 5 (the state shown in Fig. 5 C), the internal pressure of the slide tube 3 and the pressure-feeding pipe 5 rises by the amount of the pressure-feeding load, and at this time, this pressure also acts on the tip 3a of the slide tube 3. I will do it. To explain this in detail with reference to FIG. 6, when pumping earth and sand, a pressure commensurate with the load is generated inside the slide cylinder 3 and the pressure pipe 5, but the pressure P is between the tip 3a of the slide cylinder 3 and the seal. It also acts between the seal 4 inside the case 6 and tries to push the slide tube 3 back. Particularly, as shown in FIG. 7, when the abutting surfaces of the tip 3a of the slide cylinder 3 and the seal 4 are tapered, the pushing back force becomes even greater. When the slide tube 3 is pushed back against the push-back force, a gap is created between the slide tube 3a and the seal 4, and earth and sand leak from the gap, reducing the pumping efficiency. In addition, the tip of the slide tube 3 may be damaged by the earth and sand flowing out from the gap.
a and the seal 4 wear out, the gap gradually becomes larger, and eventually the balance with the pumping load is lost, and the entire amount of earth and sand in the slide tube 3 flows out of the gap, making pumping impossible.

An object of the present invention is to provide an earth and sand pumping device that has a simple configuration and can prevent the slide tube from being pushed back due to the pumping load during earth and sand pumping.

[Means for solving problems]

In order to achieve the above object, the present invention has a hydraulic switching valve for the sliding cylinder jack, a hydraulic switching valve for the piston jack, and a hydraulic switching valve for the bottom side of the sliding cylinder jack and the piston jack through the respective hydraulic switching valves during the pressure feeding process. It is equipped with a switching valve operating means that applies hydraulic pressure to the bottom side, and generates hydraulic pressure on the slide cylinder jack to counter the push-back force acting on the tip of the slide cylinder due to the pumping load during the pumping process. Features.

[Effect]

The present invention aims to prevent the slide tube from being pushed back by generating hydraulic pressure on the slide tube jack to counteract the push-back force exerted on the tip of the slide tube due to the pressure-feeding load during the pressure feeding process. . Therefore, when hydraulic pressure is applied to the bottom side of the piston jack through the hydraulic switching valve of the piston jack and the earth and sand pumping piston is slid forward, the hydraulic pressure is also applied to the bottom side of the sliding jack through the hydraulic switching valve of the sliding jack. Apply hydraulic pressure.

〔Example〕

Fig. 1 shows a hydraulic circuit according to an embodiment of the present invention, and Fig.
The figure shows the electrical circuit.

In FIG. 1, 11 is a hydraulic switching valve for the slide cylinder jack 8, and 12 is a hydraulic switching valve for the piston jack 7. The hydraulic switching valve 11 is an electromagnetically operated 4-port switching valve in which all ports are closed in the neutral position, and its A port is connected to the slide cylinder jack 8.
The B port is connected to the bottom oil inlet/outlet 8a of the slide cylinder jack 8, and the hydraulic switching valve 12 is an electromagnetically operated two-port switching valve, and the A port is connected to the piston jack. 7 is connected to the bottom side oil inlet/outlet 7a. In order to simplify the device, the hydraulic unit consisting of the relief valve 13, hydraulic pump 14, and oil tank 15 is shared by the slide cylinder jack 8 and the piston jack 7, and the P port of the hydraulic switching valve 11 and the hydraulic switching valve 12 are The P port is connected to the hydraulic pressure supply side of the hydraulic unit, and the R port of the hydraulic switching valve 11 and the rod side oil inlet/outlet port 7b of the piston jack 7 are connected.
is connected to the drain return side of the hydraulic unit to form a hydraulic circuit.

The switching valve operating means includes operating solenoids a and b for the hydraulic switching valve 11 shown in FIG. 2, operating solenoids a for the hydraulic switching valve 12, relays SC, SN,
It is composed of an electric circuit consisting of AN and limit switches 16, 17, and 18. In Fig. 2, 19, 20, 21 are coils of relays SC, SN, AN, 22, 23, 24, 25 are relays SC,
SN, AN, normally open contacts, 26, 27, 28 are relay SC, SN, AN normally closed contacts, 29, 30, 3
1 is the self-holding contact of relays SC, SN, and AN.
Further, as shown in FIG. 5, the limit switches 16, 17, and 18 turn on when the slide tube 3 is in the retracted position,
The limit switch 18 is turned on when the earth and sand pumping piston 2 is in the forward position, and the limit switch 17 is turned on when the earth and sand pumping piston 2 is in the forward position.

In this embodiment, P ₁ is the working hydraulic pressure of the piston jack 7 during the pumping process [Kg/cm ² ], P ₂ is the working hydraulic pressure of the slide cylinder jack 8 during the pumping process [Kg/cm ² ],
A _M is the bottom side pressure receiving area of the piston jack 7 [cm ² ], A _S is the bottom side pressure receiving area of the sliding cylinder jack 8 [cm ² ], A _P is the pressure receiving area of the earth and sand pumping piston 2 [cm ² ]A Let _D be the pressure-receiving area [cm ² ] of the slide tube tip 3a that receives the reaction force of the pumping load, N _M be the number of piston jacks 7 [pieces], and N _S be the number of slide tube jacks 8 [pieces]. In this case, the above specifications are selected so that the relationship of equation (1) below holds.

_{NM ​ ​ ​ ​ ​ ​ ​}
The right side represents the hydraulic pressure generated on the slide cylinder jack 8 in opposition to the push-back force acting on a.

Next, the operation of the earth and sand pumping device in this embodiment will be explained with reference to FIGS. 1, 2, and 5.

() Sediment intake process: When the slide cylinder 3 is fully compressed, the limit switch 16 is turned on, and the coil 19 of the relay SC is energized to self-hold.
When the normally open contact 23 of the relay SC is turned on, the solenoid a of the hydraulic switching valve 11 is energized and the A port of the hydraulic switching valve 11 is connected to the P port and the B port is connected to the R port. Pressure oil flows into the bottom side. As a result, the slide tube 3 moves forward, and the sediment storage tank 1
The soil inside is taken into the slide tube 3.

() Earth and sand pumping process; the slide tube 3 moves forward,
At the same time as the tip 3a hits the seal 4, the limit switch 18 is turned on, and the coil 20 of the relay SN is energized and self-maintained. relay
By turning on the normally open contacts 22 and 25 of SN and turning off the normally closed contact 26, solenoid a of the hydraulic switching valve 11 and solenoid a of the hydraulic switching valve 12 are energized, and the relay SC is released from self-holding. . Then, by communicating the A port and the P port of the hydraulic switching valve 12, pressure oil flows into the bottom side of the piston jack 7, and the earth and sand pumping piston 2 is slid forward to forcefully transport the earth and sand in the slide tube 3. do. At this time, a hydraulic pressure P ₁ commensurate with the pumping load (earth pressure) acts on the bottom side of the piston jack 7, but at the same time, the solenoid a of the hydraulic switching valve 11 is energized, and the A port and P port of the hydraulic switching valve 11 are energized. Since they are in communication, almost the same hydraulic pressure P ₂ (≒P ₁ ) also acts on the bottom side of the slide cylinder jack 8. In this embodiment, the relationship expressed by equation (1) is satisfied, so the hydraulic pressure that presses the slide tube 3 toward the seal 4 side is always equal to the pushing back force that acts on the slide tube tip 3a due to the pumping load. or larger. Therefore, the slide tube 3 is not pushed back, and the tip end 3a is pressed against the seal 4 by hydraulic pressure according to the pumping load, making it possible to completely seal and isolate the inside of the slide tube 3 and the inside of the sediment storage tank 1. becomes.

() Suction process: When the earth and sand pumping piston 2 moves forward and reaches the position where it completes pushing out the earth and sand in the slide cylinder 3, the limit switch 17 is turned on, and the coil 21 of the relay AN is energized to self-hold. The normally open contact 24 of the relay AN is turned on and the normally closed contact 27 is turned off, so that the solenoid b of the hydraulic switching valve 11 is energized.Meanwhile, since the self-holding of the relay SN is released, the hydraulic switching valve 11 is Solenoid a and solenoid a of the hydraulic switching valve 12 are de-energized. Then, the B port of the hydraulic switching valve 11 becomes the P port,
With the A port communicating with the R port, pressure oil flows into the rod side of the slide cylinder jack 8.
Slide the slide tube 3 back. At this time,
The base end of the slide tube 3 engages with the flange 9 of the earth and sand pumping piston 2, and the earth and sand pumping piston 2 is simultaneously slid back.

Thereafter, the above-mentioned operations (), (), () are repeated to pump the earth and sand.

FIG. 3 shows a hydraulic circuit according to another embodiment of the present invention, and FIG. 4 shows its electric circuit.

The hydraulic circuit of this embodiment shown in FIG. 3 is an electromagnetically operated four-port switching valve 11' of the slide cylinder jack 8, in which the P, A, and B ports are in communication at the neutral position, and the R port is closed. The only difference from the hydraulic circuit shown in FIG. 1 is that a valve is used.

The electric circuit shown in FIG. 4 has almost the same configuration as the electric circuit shown in FIG. 2, except that the normally open contact 23 of the relay SC is connected to the solenoid a of the hydraulic switching valve 11.

In this embodiment, P ₁ is the working hydraulic pressure of the piston jack 7 during the pumping process [Kg/cm ² ], P ₂ is the working hydraulic pressure of the slide cylinder jack 8 during the pumping process [Kg/cm ² ],
A _M is the bottom side pressure receiving area of the piston jack 7 [cm ² ], A _S is the bottom side pressure receiving area of the sliding cylinder jack 8 [cm ² ], A _SR is the sliding cylinder jack 8
pressure receiving area on the rod side [cm ² ], A _P is the pressure receiving area of the earth and sand pumping piston 2 [cm ² ], A _D is the pressure receiving area of the slide cylinder tip 3a that receives the reaction force of the pumping load [cm ² ], N _M
When is the number of piston jacks 7 [pieces] and N _S is the number of slide cylinder jacks 8 [pieces], the above specifications are selected so that the relationship of equation (2) below holds.

N _M ×P ₁ ×A _M ／A _P ×A _D ≦N _S ×P ₂ × (A _S −A _SR ) ...(2) In the above equation, as in equation (1), the left side is the pumping process. The right side represents the hydraulic pressure generated in the slide cylinder jack 8 in opposition to the push-back force that acts on the slide cylinder tip 3a.

Next, the operation of the earth and sand pumping device in this embodiment will be explained with reference to FIGS. 3, 4, and 5.

(') Sediment intake process: When the slide cylinder 3 is fully compressed, the limit switch 16 is turned on, and the coil 19 of the relay SC is energized to self-hold.
When the normally open contact 23 of the relay SC is turned on, the solenoid a of the hydraulic switching valve 11 is energized and the A port of the hydraulic switching valve 11 is connected to the P port and the B port is connected to the R port. Pressure oil flows into the bottom side. As a result, the slide tube 3 moves forward, and the sediment storage tank 1
The soil inside is taken into the slide tube 3.

(') Earth and sand pumping process; the slide tube 3 moves forward,
At the same time as the tip 3a hits the seal 4, the limit switch 18 is turned on, and the coil 20 of the relay SN is energized and self-maintained. relay
Normally open contact 25 of SN turns on, normally closed contact 2
6 is turned off, the solenoid a of the hydraulic switching valve 12 is energized, and the relay SC is released from self-holding. Then, the A port and P port of the hydraulic switching valve 12 communicate with each other, so that pressure oil flows into the bottom side of the piston jack 7, and the earth and sand pumping piston 2 is slid forward to forcefully transport the earth and sand in the slide tube 3. . At this time, a hydraulic pressure P ₁ commensurate with the pumping load (earth pressure) acts on the bottom side of the piston jack 7, but the hydraulic pressure switching valve 11
is in the neutral position and the P, A, and B ports are in communication, so almost the same hydraulic pressure P ₂ (≒P ₁ ) also acts on the bottom side and rod side of the slide cylinder jack 8, and the bottom side and the rod side A hydraulic pressure corresponding to the product of the difference in the pressure-receiving area and the oil pressure P ₂ presses the slide cylinder 3 against the seal 4 side. In this embodiment, the relationship of equation (2) is satisfied, so the hydraulic pressure that presses the slide tube 3 toward the seal 4 side is always equal to the pushing back force acting on the slide tube tip 3a due to the pumping load, or It will be bigger than that. Therefore, slide tube 3
Without being pushed back, the tip portion 3a is pressed against the seal 4 by hydraulic pressure according to the pumping load, making it possible to completely seal and isolate the inside of the slide cylinder 3 and the inside of the sediment storage tank 1.

(') Suction process: When the earth and sand pumping piston 2 moves forward and reaches the position where it completes pushing out the earth and sand in the slide cylinder 3, the limit switch 17 is turned on, and the coil 21 of the relay AN is energized to self-hold. By turning on the normally open contact 24 of relay AN and turning off the normally closed contact 27,
The solenoid b of the hydraulic switching valve 11 is energized, while the self-holding of the relay SN is released, so the solenoid a of the hydraulic switching valve 12 is not energized.
Then, by communicating the B port with the P port and the A port with the R port of the hydraulic switching valve 11, pressure oil flows into the rod side of the slide cylinder jack 8, causing the slide cylinder 3 to slide back. At this time, the base end of the slide tube 3 is connected to the earth and sand pumping piston 2.
The earth and sand pumping piston 2 is also slid back at the same time.

Thereafter, the above-mentioned operations ('), ('), and (') are repeated to pump the earth and sand.

Although the embodiments of the present invention have been described above, the present invention is not limited to the configurations shown in the embodiments. For example, the hydraulic unit that operates the piston jack 7 and the hydraulic unit that operates the slide cylinder jack 8 may be separate, and the working hydraulic pressure of the piston jack 7 and the slide cylinder jack 8 during the pumping process is P ₁ ≠ It may be _P2 .

Furthermore, the hydraulic switching valves 11 and 12 are not limited to ordinary spool switching valves, but may be of any functionally equivalent type.

[Effect of idea]

According to the present invention, hydraulic pressure is generated in the slide cylinder jack to counter the push-back force acting on the tip of the slide cylinder due to the pumping load during the pressure feeding process, and the hydraulic pressure presses the tip of the slide cylinder against the seal to push the slide cylinder inside the slide cylinder. Since the inside of the sediment storage tank can be completely isolated, good sediment pumping efficiency can be maintained. Furthermore, since no separate mechanism such as a mechanical stopper for holding the slide cylinder in the forward position is required, the apparatus can be constructed simply and at low cost.

[Brief explanation of drawings]

Figure 1 is a hydraulic circuit diagram of one embodiment of the present invention, Figure 2 is a hydraulic circuit diagram of an embodiment of the present invention.
Figure 3 is a hydraulic circuit diagram of another embodiment of the present invention, Figure 4 is a diagram of the same electric circuit, Figure 5 is an explanatory diagram of the operation of the earth and sand pumping device, and Figure 6 is Figure 5. FIG. 7 is an enlarged view showing an example of the S section, and FIG. 7 is an enlarged view showing another example of the S section in FIG. 1... Sediment collection tank, 2... Sediment pressure feeding piston, 3... Slide tube, 4... Seal, 5... Pressure feeding pipe, 7... Piston jack, 8... Slide tube jack, 11... Slide Hydraulic switching valve for cylinder jack, 12... Hydraulic switching valve for piston jack, a, b... Solenoid for switching valve operation, SC, SN, AN... Relay for switching valve operation, 1
6, 17, 18...Limit switch for operating the switching valve.

Claims (1)

[Scope of utility model registration request] a sediment storage tank; a slide tube having an open end and sliding back and forth linearly within the sediment storage tank;
An earth and sand pumping piston that reciprocates in the axial direction of the slide cylinder, a slide cylinder jack that reciprocates the slide cylinder, a piston jack that reciprocates the earth and sand press piston in the axial direction, and an earth and sand reservoir. A pressure-feeding pipe connected to the tank is provided, the slide tube is slid forward to take in earth and sand into the slide tube, and the inside of the slide tube and the inside of the sediment storage tank are sealed and isolated, and the soil-feeding piston is slid forward. In an earth and sand pumping device that pushes out earth and sand in a slide cylinder and pumps it into a pressure pipe, the hydraulic switching valve of the slide cylinder jack, the hydraulic switching valve of the piston jack, and the hydraulic switching valve of the piston jack are connected to the slide cylinder through the respective hydraulic switching valves during the pumping process. The slide cylinder jack is equipped with a switching valve operating means that applies hydraulic pressure to the bottom side of the piston jack and the bottom side of the piston jack, and the slide cylinder jack is provided with a switching valve operating means that applies hydraulic pressure to the bottom side of the piston jack. An earth and sand pumping device characterized in that the earth and sand is generated as hydraulic pressure.