JPH01172686A - Fluid way switch - Google Patents

Abstract

PURPOSE:To prevent variation in stroke due to leak of working oil by having the contact faces of a pair of manifolds pressed to be fit with each other using a holding mechanism. CONSTITUTION:A covered cylindrical holding member 66 having an upper manifold 10 press-fitted to a lower manifold 38 is tightened with a bolt 67 on the upper face of the lower manifold 38. A hole 69 through which the lower third stage part 40c of the upper manifold 40 is inserted is formed on the top board 68 of the holding member 66 and a bearing 69 turnably supporting the upper manifold 40 is mounted between the lower face of the top board 68 and the lowest stage part 40a of the upper manifold 40. The top stage part 40d of the upper manifold 40 projects from the upper face of the holding member 66 and a handle 72 is tightened the top part 40d.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a flow path switching device used, for example, in a concrete pump to switch the pumping pressure of fresh concrete.

[Prior Art] Conventionally, as a fresh concrete pumping device for a concrete pump, one having a configuration as shown in FIG. 8 is known. This pumping device Δ has two actuators 1.
2, a pressure-feeding piston 5:6 fixed to the protruding end of the rod 3.4 of this actuator 1.2, and this pressure-feeding piston 5.6 are slidably arranged and communicated with the hopper 7. The cylinder 1 of the actuator 1.2 is composed of two pressure-feeding cylinders 8.9.
The 0.11 head side boats 12 and 13 are connected by a connecting pipe 14, and the rod side boats 15 and 16 are each connected to a flow path switching valve (not shown). This pressure feeding device A connects the flow path switching valve to the rod side boat 15.
16 to drive the rods 3, 4 of the actuators 1, 2 and the piston 5.6, and the piston 5.6 sucks the ready-mixed concrete into the pressure-feeding cylinder 8.9; Further, the fresh concrete is forced to be fed by the discharge operation to the outside of the cylinder 8.9. (During this movement, the movement in only one direction is
(indicated by an arrow in the figure).

However, in such a pumping device, in order to increase the pumping pressure of fresh concrete while keeping the hydraulic pressure supplied to the actuator 1.2 constant, it is necessary to adjust the inner diameter of the pressure cylinder 8.9 and the piston 5.6. It is necessary to reduce the outer diameter of the pressure cylinder 8.9.
Problems such as a decrease in the discharge amount due to a decrease in the volume of the pump and the fact that it takes a lot of time to replace the piston 5.6 and the pressure-feeding cylinder 8.9 remain.

In addition, the 9th pump is used as a pumping device that increases the pumping pressure of fresh concrete without replacing the piston or pumping cylinder.
A pressure feeding device B as shown in the figure has been considered. This pressure feeding device B is a rod-side boat t of the actuator 1.2.
5 and 1e are connected to each other by a connecting pipe 17, and the head side boats 12 and 13 are each connected to a flow path switching valve (
(not shown), and the rest of the structure is the same as the conventional pumping device. This pressure feeding device B is
Pressure oil supplied from the flow path switching valve is transferred to the actuator 112.
cylinder 10. Piston 18.1 located in II
9 wide side (side where rod 3.4 is not fixed)
By receiving pressure at the piston 5.6, the pressure of fresh concrete being pumped by the pumping piston 5.6 is increased.

This pumping device B has an actuator l.

By changing the pressure-receiving surface of piston 18 and 19 in No. 2 that receives pressure oil supplied from the flow path switching valve, the pressure for pumping fresh concrete is increased, so it is necessary to change the diameter of the pressure-feeding cylinder and piston. There is no connecting pipe 14.17
It is still complicated to change the connection position of the flow path switching valve and the connection between the flow path switching valve and each boat, and the problem is that switching between high pressure and low pressure cannot be performed immediately.

Therefore, in order to solve the above problems, we decided to
A technique as shown in ηSho 55-24555 has been proposed. This has a valve seat body with a cylindrical bore (cylindrical inner surface) and a cylindrical rotary valve element rotatably fitted to this cylindrical bore, so the valve note body and valve element A flow path for hydraulic oil is formed in each of the actuators and the valve body, and the flow path in the valve body is connected to each boat of the actuator and a hydraulic power source. A drive motor is provided to rotate the valve element, and by rotating the valve element and changing the flow path of the valve seat body, switching between high pressure and low pressure can be performed instantly.

[Problems to be Solved by the Invention] In the conventional technology as described above, the valve element is fitted into the bore of the valve seat body, and it is difficult to apply a pressure of more than a certain level between these surfaces. I can't. In other words, since there is a certain gap between these cylindrical sliding surfaces, leakage to each boat always occurs, causing changes in the stroke of the hydraulic cylinder on the closing side and a decrease in efficiency, which reduces the efficiency of pumping. There is a problem.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a pair of manifolds each having a hydraulic oil flow path opened at a joint surface of the other, and The structure includes a holding mechanism that presses and holds the manifold through the joint surface so as to be relatively rotatable. Note that the pressure may be made variable to facilitate the switching operation.

The structure of the manifold itself is simplified by forming one manifold with an internal flow path that opens only to the joint surface, and connecting only the flow path of the other manifold to an external hydraulic power source or actuator. Further, by making one of the manifolds rotatable and fixing the other manifold, it becomes easy to connect the hydraulic piping around the manifold.

Furthermore, a cylindrical shape may be provided to protrude from the opening of one of the channels so that the pressure contact force on the joint surface can be effectively applied.

[Function] In this type of flow switching device, the hydraulic oil flow paths open at the joint surfaces of the manifolds, so if these openings are appropriately arranged, the manifold can be moved parallel to the joint surfaces. The connection of the flow paths between the manifolds is changed by relative rotation within the plane. The joint surfaces of the manifolds are pressed against each other by a holding mechanism to prevent changes in stroke due to leakage of hydraulic oil.

[Embodiment] The present invention will be described in detail below based on an embodiment shown in FIGS. 1 to 7.

First, referring to FIG. 5, a concrete pump pumping device C in which the flow path switching device S of the present invention is used will be explained. This pressure feeding device C includes a pair of actuators 20.21 driven by hydraulic pressure, a flow path switching valve 22 connected to the actuators 20.21, one end of which is fixed to the actuator 20.21, and the other end of which is fixed to the actuator 20.21. a pair of pressure-feeding cylinders 24.25 fixedly connected to the hopper 23; a flow path switching device S disposed between the actuator 20.21 and the flow path switching valve 22; and the actuator 20.2.
1, a hydraulic pump 27 that supplies pressure oil via a flow path switching valve 22 and a flow path switching device S.

Said actuator 20.21 is constructed in the form of a double-acting single-rod cylinder, comprising a cylinder 28.29 and a piston 30 slidably arranged in this cylinder.
．． 31, one end is fixed to this piston 30.31,
Rods 32 and 33 whose other ends protrude from the cylinder 28.29, a head side boat 34.35 provided on the head side of the cylinder 28.29, and a cylinder 28.29.
1: Rod side boat installed on the 1st side 36.37
It has

The flow path switching device S includes a fixed lower manifold 38,
The upper manifold 40 is pressed against the lower manifold 38 by a holding mechanism 39 and rotatably held via the joint surface thereof. The lower manifold 38 includes a pair of mutually independent first supply passages 41.4, one end of which communicates with the head side boat 34.35, and the other end of which opens at the joint surface with the upper manifold 40.
2, a pair of mutually independent second supply passages 43.44, one end of which communicates with the rod-side boat 36.37, and the other end of which opens at the joint surface with the upper manifold 40;
A pair of mutually independent third supply passages 45 whose one end communicates with the flow passage switching valve 22 and whose other end opens at the joint surface with the upper manifold 40. '46, etc., and are connected by high pressure hoses 47 to 52, respectively.

On the other hand, the upper manifold 40 is formed in the shape of a rotating body having four step portions 40a, .
In the bonded state (see FIG. 6), the first supply path 41
．． 42 are brought into communication with each other, and from this first joined state, the upper manifold 40 is connected to the lower manifold 38.
In the second joined state (see Fig. 7) in which the parts are rotated 180 degrees parallel to the joining surface and joined
A first communication passage 53 that communicates with each other, and a first supply passage that communicates with the second supply passage 43.44 and third supply passage 45.46 in the first joined state and the first supply passage in the second joined state. A pair of second communication passages 54, 55 are formed which communicate the passages 41, 42 and the third supply passages 45, 46. Furthermore, a fourth supply path 57 is formed in the lower manifold 38 and is connected to the hydraulic pump 27 by a high pressure hose 56. 3 communication path 5
8 to communicate with the first communication path 53. The openings in the joint surfaces of the supply paths 41 to 46 are centered on the openings in the joint surface of the fourth supply path 57 (located at the center of the joint surface), and the first supply path 41.
42 and the second supply path 44, 43 are located in point-symmetrical positions,
Further, the openings of the third supply passages 45, 46 are positioned symmetrically with respect to each other. Also, upper manifold 4
0, the openings at both ends of the first communication path 53 are the openings at one end of the second and third communication paths 54 and 55, respectively;
Furthermore, the openings at the other ends of the second and third communicating paths 54 and 55 are arranged point-symmetrically with respect to the opening of the fourth communicating path 58 (located at the center of the joint surface).

In other words, each of the above-mentioned flow paths is arranged at the center and at equal water division points on the concentric circles on the joint surface of the manifold 38, 40.

As shown in FIG. 1, each of the supply channels 41 to 46.57 has a vertical portion 61 that opens to the joint surface, and a horizontal portion that extends horizontally from the lower end of this vertical portion 61 and opens to the side surface of the lower manifold 38. This vertical part 6
1 is fitted with a cylindrical nozzle 63 and a coil spring 64 that biases the nozzle 63 upward. This nozzle 6
3, a seal ring 65 is attached to the sliding surface with the vertical part 61, and the upper end is the vertical part 6! A step 63a with a larger diameter is formed so as to protrude from the joint surface.

A capped cylindrical holding member 66 that holds the upper manifold 70 in pressure contact with the lower manifold 38 is fixed to the upper surface of the lower manifold 38 by bolts 67. A hole 69 is formed in the top plate 68 of this holding member 6G, through which the lower third stage portion 40c of the upper manifold 40 is inserted, and between the lower surface of the top plate 68 and the lowermost stage 40a of the upper manifold 40, a hole 69 is formed. , a bearing 69 that rotatably supports the upper manifold 40 is mounted. The uppermost part 40d of the upper manifold 40 protrudes from the upper surface of the holding member 66, and the uppermost part 40d has a connecting member 70 in the shape of a disc with holes.
The connecting member 7o is attached via a locking key 71, and a handle 72 is fixed to the side end of the connecting member 7o. The handle 72 is provided on the upper surface of the holding member 66.
A pair of stoppers 73 and 74 that position the upper manifold 40 by coming into contact with the upper manifold 40 are provided at substantially symmetrical positions with respect to the center of rotation.

Note that a seal member 75 is provided at the connection portion between each of these members.
is taken in an appropriate amount. In addition, 76.77 is the connecting member 70
78 is inserted into a recess 79 on the upper surface of the holding member 66 via a spring 80 and abuts against a groove 81 formed in the circumferential direction on the lower surface of the connecting member 70. These are balls that make contact with each other and allow the connecting member 70 to slide smoothly. The holding member 66 and the coil spring 64 constitute the holding mechanism 39.

Moreover, what is indicated by numerals 91 and 92 is the rod 32,
33, and the pressure feeding cylinder 24.25
A pressure-feeding piston slidably disposed within the high-pressure hose 56, designated by the reference numeral 93, is a valve disposed at an appropriate position on the high-pressure hose 56.

Next, let me explain how this invention works.

First, the operation for low-pressure pumping will be explained. 6th
The figure shows the flow path switching device S in which the position of the upper manifold is set to obtain low pressure, and the flow of pressure oil.The handle 72 is in contact with the first stopper, and the flow path switching device S!
1. The lower manifold 38 and the upper manifold 40 of S are fixed in a first joined state so as to communicate as follows. That is, the first supply paths 41 and 42 are communicated with each other through the first communication path 53, and one second supply path 43 and one third supply path 45 are communicated with each other through one of the third supply paths 45 and 42. Furthermore, the other second supply path 44 and the other third supply path 46 are communicated through another second communication path 55.

In this way, pressure oil is supplied or moved as follows by the set flow path switching device S.

That is, the pressure oil sent out from the hydraulic pump 27 is transferred to the third supply path 45 on the side selected by the flow path switching valve 22.
High pressure hose 5! is supplied via the second communication path 54
, the second supply path 43, the high pressure hose 49, and the rod side boat 36 into the cylinder 28. The pressure oil supplied into the cylinder 28 presses the rod side of the piston 30 and moves the piston 30 together with the rod 32 in the backward direction (to the left in FIG. 6). In addition, the above cylinder 2
The closed bend located on the head side of the piston 30 in the piston 30 is compressed by the above-described movement of the piston 30, and the head side boat 34, the high pressure hose 47, the first supply path 41, the first
The communication path 53 of the cylinder 2, the first supply path 42, the high pressure hose 48, and the head side boat 35 of the cylinder 29
9. The closing curve supplied into the cylinder 29 in this way presses the head side of the piston 31,
Piston 3! along with the rod 33 in the forward direction (to the right in FIG. 6). Furthermore, the ura located on the rod 33 side of the piston 31 in the cylinder 29 is compressed by the above-described movement of the piston 31, and the rod-side boat 37, the high-pressure hose 50, the second supply path 44, and the second The oil is discharged through the communication path 55, the third supply path 46, the high pressure hose 52, and the flow path switching valve 22 to an oil tank (not shown). The oil flow described above is a flow that moves one rod 32 in the backward direction and the other rod 33 in the forward direction.
In order to operate the flow path switching valve 2 in the opposite direction,
2 may be operated to supply pressure oil from the hydraulic pump 27 to the third supply path 46. This causes the pressure oil to flow in the opposite direction to that described above, so both rods 32
, 33 are performed in the opposite direction.

Next, high-pressure pumping will be explained.

To switch from low pressure to high pressure, grasp the handle 72 of the flow path switching device S and rotate the upper manifold 40 by 180 degrees with respect to the lower manifold 38 parallel to the joint surface. As a result, the handle 72 comes into contact with the second stopper 74, resulting in a second joined state as shown in FIG. That is, one first supply path 41 and one third supply path 4
5 through the other second communication path 55, and the other first supply path 42 and the other third supply path 4G are connected through one second communication path 54, and further, Second supply path 43
and 44 are communicated through a first communication path 53.

With the flow path switching device S set in this way, the pressure oil supplied from the hydraulic pump 27 is supplied to the head side of one cylinder 28 as shown by the arrow in FIG. The piston 30 is pushed from the head side to move the piston 30 forward. Furthermore, due to the setting of the flow path switching device S described above, the oil located on the rod side of each of the cylinders 28 and 29 is in a closed curve, so the forward movement of one piston 30 compresses this closed curve. This closing movement causes the other piston 31 to move in the backward direction. Furthermore, the retracted piston 31
Oil located on the head side of the oil tank passes through the head side boat 35, the other first supply path 42, one of the second communication paths 54, the other third supply path 46, and the flow path switching valve 22. is discharged to. As described above, the switching operation of the flow path switching valve 22 causes the oil to flow in the opposite direction, thereby causing the pistons 30, 31 to move in opposite directions.

Note that the valve 93 is normally closed, and when the amount of closed bending changes, for example, decreases, by opening this valve 93, the pressure oil from the hydraulic pump 27 is released into the closed circuit. The water is supplied from the fourth υ (feeding path 57 and third communication path 58).

In this way, by relatively rotating the lower manifold 38 and the upper manifold 40 of the flow path switching device S and changing the connection position of the flow paths on the joint surface, the pressure oil supplied from the hydraulic pump 27 can be transferred to the actuator 28. .29 is supplied to the rod side of the piston 30.31 to obtain low-pressure pumping,
Moreover, it is possible to obtain high-pressure pumping by supplying it to the head side of the piston 30, 31.

In the two-step process, switching from low-pressure pumping to high-pressure pumping or vice versa normally does not need to be done during pumping of concrete, so either the operation of the hydraulic pump 27 is stopped or the flow path switching valve 22 It is sufficient to carry out the switching with the switch in the neutral state. If this is done, there will be no problem even if the supply passages having adjacent openings of the lower manifold 38 are communicated with each other through the communication passage of the upper manifold 40 during the switching. The upper manifold 40 and the lower manifold 38 are not directly connected, but are connected via a cylindrical nozzle 63 provided in the vertical part 61 of the flow path of the lower manifold 38. Even though the pressure on the joint surface of the upper manifold 40 is set quite high by the coil spring 64, its area is small and the pressure on the joint surface of the manifold 38.40
The pressing force that acts directly on each other is not so large. Furthermore, the joint surface of the upper manifold 40 is finished smoothly, and the torque amplification effect of the handle 72 allows the upper manifold 40 to be rotated sufficiently smoothly by hand.

On the other hand, during normal concrete pumping, the flow path switching valves 22 are switched alternately in each joint state, and therefore the pressure changes in each connected flow path at the joint surface of the flow path switching device S. , coil spring 64
Since the nozzle 63 is pressed against the upper manifold 40, there is no leakage at the joint surface, and the actuator 20
．． There is no change in the stroke of 21. In this case, the contact pressure of the coil spring 64 is between the nozzle 63 and the upper manifold 1;
Since it acts only on the joint surface of 0, the small coil spring 64
However, it has the advantage that it provides a sufficient pressing force, does not require a large elastic member, and can perform the switching operation with a small force as described above.

In the above embodiment, the joint surfaces of the upper and lower manifolds 38° and 40 are circular, and the openings of the respective flow paths are arranged at points symmetrical to the center of the joint surface and the surrounding points, thereby making it possible to easily switch complicated piping. Easy and quick operation. In the above, six openings are arranged on the same circle, but the openings are not limited to this, and may be more or less than this, and may be arranged on circles with different diameters. Further, in the above description, there are only two switching positions, but there may be more switching positions depending on the purpose of use.

In the above embodiment, the flow path of the upper manifold 40 is opened only to the joint surface, and the upper manifold is rotated, so the connecting pipe (high pressure hose) is connected only to the lower manifold 38. The switching operation does not cause the piping to move, allowing for smooth operation without posing a danger to the surrounding area. However, depending on the purpose of use of this flow path switching device, even if both flow paths of both manifolds can be connected to the outside, 1;

This is because the movement of the piping can follow the movement of the manifold.

[Effects of the Invention] As described in detail above, the present invention includes a pair of manifolds in which hydraulic oil flow paths are opened at mutual joint surfaces;
The structure is equipped with a holder+I which presses and holds these manifolds through the joint surface so that they can rotate freely, so complex hydraulic circuits can be switched with simple operations, and the joint surface Since there is no 411 leakage, there is no reduction in efficiency due to changes in the stroke of the actuator.

Furthermore, the structure is simple and easy to manufacture, and the device itself is compact, easy to mount, and does not take up much space.

[Brief explanation of the drawing]

1 to 4 show a flow path switching device according to an embodiment of the present invention, in which FIG. 1 is an elevational sectional view, FIG. 2 is a plan view, and FIG. 3 is an ITI- n! 4 is a side view, FIGS. 5 to 8 are diagrams showing the case where the flow path switching device is applied to a fresh concrete pumping device, FIG. 5 is its configuration diagram, and FIG. 6 is a side view. 7 is a diagram showing a hydraulic flow path during low-pressure pumping, FIG. 7 is a diagram showing a hydraulic flow path during high-pressure pumping, and FIGS. 8 and 9 are diagrams showing a conventional fresh concrete pumping device. 38... Lower manifold, 39... Holding mechanism, 40... Upper manifold, 41.42... First supply path, 42.44...
...Second supply path, 45.4 (i...Third
supply path, 53...first communication path, 54.55...second communication path, 57...
- Fourth supply path, 58...Third communication path, 63
... Nozzle (cylindrical body), 64 ... Coil spring, 66 ... Holding member, 72 ... Handle.

Claims (4)

[Claims] (1) Equipped with a pair of manifolds in which hydraulic oil flow paths are opened to each other's joint surfaces, and a holding mechanism that presses and holds these manifolds in relative rotatable contact via the joint surfaces. A flow path switching device characterized by: (2) The flow path switching device according to claim 1, wherein the flow path of one of the manifolds is open only to the joint surface. (3) The flow path switching device according to claim 2, wherein one of the manifolds is rotatable and the other manifold is fixed. (4) The flow path switching device according to any one of claims 1 to 3, wherein one of the flow path openings of the manifold is provided with a cylindrical body protruding from the joint surface.