JP2836999B2 - Electa device of shield excavator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an erector device for a shield excavator.

[0002]

2. Description of the Related Art A conventional shielded excavator erector device will be described with reference to FIGS. 4 to 6. Referring to FIGS. 4 and 5, reference numeral 14 denotes a swivel ring. (Not shown) is mounted on the inner peripheral surface of the excavator body so as to be capable of turning around the central axis.

[0003] In Fig. 4, reference numeral 16 denotes a turning hydraulic motor for turning the turning ring 14, 15 in Figs. 4 and 5 denotes an elevating guide member attached to the left and right sides of the turning ring 14, and 22 denotes a respective elevating guide member 15. The attached guide sliding bracket 21 is an inner cylinder supported so as to be able to move up and down by the guide sliding bracket 22, reference numeral 20 is an inner cylinder cover covering the respective inner cylinder 21, and each of the inner cylinder covers 20 is the above-mentioned respective inner cylinder cover. It is attached to the elevating guide member 15.

In FIGS. 4 to 6, reference numeral 5 denotes an arm attached to each of the inner cylinders 21, and reference numerals 6, 7 denote lifting jacks of left and right lifting devices.
The cylinders of the lifting jacks 6 and 7 are pivotally supported at the distal ends of the lifting guide members 15, and the piston rods of the lifting jacks 6 and 7 are pivotally supported at both left and right ends of the arm 5. 17 is a segment gripping mechanism, 18 is a posture control mechanism, 31 is a gripping segment, and the segment gripping mechanism 17
Is attached to the arm 5 via the attitude control mechanism 18.

In FIG. 6, reference numeral 1 denotes a power unit, 2 denotes an oil tank, 3 denotes a relief valve, and 4 denotes an electromagnetic switching valve, 4a, which is provided in a hydraulic circuit between the power unit 1 and the lifting jacks 6, 7. 4b is a coil of the electromagnetic switching valve 4, 23,
Reference numeral 24 denotes a branch point of the hydraulic circuit, reference numeral 9 denotes an extension port of the lifting jacks 6 and 7, and reference numeral 8 denotes a compression port of the lifting jacks 6 and 7.

The coil 4a of the solenoid-operated switching valve 4 is excited, the spool of the solenoid-operated switching valve 4 is moved to the left, and the hydraulic oil from the power unit 1 is discharged from the solenoid valve 4 to the extension ports of the lifting / lowering jacks 6,7. 9 → Send to the head side pressure chambers of the lifting / lowering jacks 6, 7 and return the hydraulic oil in the rod side pressure chambers of the lifting / lowering jacks 6, 7 to the compression side port 8 → the electromagnetic switching valve 4 → the oil tank 2; 7 is operated in the extension direction to move the arm 5 radially outward.

When the oil pressure of the power unit 1 exceeds the set value of the relief valve 3, the pressure oil flowing from the power unit 1 to the electromagnetic switching valve 4 is returned to the oil tank 2 via the relief valve 3. Conversely, the coil 4b of the electromagnetic switching valve 4 is excited, the spool of the electromagnetic switching valve 4 is moved rightward, and the pressure oil from the power unit 1 is discharged from the electromagnetic valve 4 to the lifting jacks 6, 7. Port 8 → lifting jacks 6, 7
To the rod-side pressure chamber, and the lifting jacks 6, 7
Then, the hydraulic oil in the head side pressure chamber is returned to the expansion side port 9 → the electromagnetic switching valve 4 → the oil tank 2 and the lifting jacks 6, 7 are operated in the contracting direction to move the arm 5 inward in the radial direction.

The hydraulic circuit extending from the electromagnetic switching valve 4 is divided at a branch point 23, and the extension side ports 9, 9 of the lifting jacks 6, 7 are separated.
If the hydraulic circuit is divided at the branch point 24 and connected to the compression side ports 8, 8 of the lifting / lowering jacks 6, 7, the stroke of the jack cannot be synchronized.
In order to synchronize the strokes with each other more precisely by installing a flohering device bar for evenly distributing the oil amount to the lifting / lowering jack 6, as shown in FIG.
The electromagnetic switching valve 4 ′ is interposed in the lifting jack 7, while the stroke meters 25, 2 are mounted in the lifting jacks 6, 7.
6 must be provided.

In this case, the pressure oil from the power unit 1 is sent to the lifting jacks 6, 7 via the electromagnetic switching valves 4, 4 ', and the lifting jacks 6, 7 are operated in the expansion and contraction directions.
At this time, the strokes of the lifting jacks 6, 7 are detected by the stroke meters 25, 26, and the resulting detection signals are fed back to the electromagnetic switching valves 4, 4 ', and the electromagnetic switching valves 4, 4' are finely adjusted. Then, the strokes of the lifting jacks 6, 7 are synchronized.

[0010]

However, the conventional shielded excavator shown in FIGS. 4 to 6 has the following problems. That is, FIG. 8 shows a coordinate system for forming segments. The gripping segment 31 that is being gripped needs to be aligned with the surface of the existing segment 33 where one ring has already been assembled and the surface of the adjacent ring 32 of the ring that is currently being assembled.

[0011] The rotation around the X axis, the vertical movement in the Y axis direction, the sliding in the Z axis direction, the rotation in the _X direction (pitching), the rotation in the _Y direction (yawing),
回 転 It is necessary to control the rotation (rolling) in the _Z direction. Among the above control items, the lifting control in the Y-axis direction by the left and right lifting jacks 6 and 7 is a large factor. If there is a difference in the strokes of the lifting jacks 6 and 7, the grip segment 31 is inclined and the grip segment 31 is tilted. 31 faces already 1
Not coincide with respect to the plane of the adjacent ring 32 of the ring are assembled actually the surface of the existing segments 33 the end of the assembly of the ring, theta to _{the Z-direction} correction (rolling) is required, in some cases, The grip segment 31 cannot be set at the assembly position.

The reason why a stroke difference occurs between the left and right lifting jacks 6 and 7 will be described with reference to FIG. Lifting jack 6,
7 is to be extended obliquely downward to the left, the weight of the arm 5, the attitude control mechanism 18, the segment gripping mechanism 17, and the gripping segment 31, which are moved by the lifting jacks 6, 7, is W, and the center of rotation of the swing ring 14 is O. Then, since the length of the arm at the point of application of O and W is L, the arm 5 causes the arm 5 to rotate counterclockwise about O with M _W = W
× L.

[0013] Shinryoku F _L that tries to stretch the lifting jacks 6 of the left-hand side is the same direction as the moment M _W, F _L is also small, left-hand side of the lifting jacks 6 can extend enough. Rather Considering the equilibrium of moments jacks are stopped, the left lift jacks 6, it is necessary to exert a holding force (contraction force) -F _L in shrinking direction, even simply by the hydraulic pressure to free the left The lifting jack 6 tries to expand. (Lifting and Shinryoku F center of the action point moments of _R of the point or lifting jacks 7 W jacks 6
It can be seen that become Chijimiryoku -F _L. Therefore, the extension force F _{R that} tries to extend the right-hand lifting jack 7
Must be greater than F _L (F _R > F _L ),
As shown in FIG. 5, the left and right lifting jacks 6 and 7 have extension side ports 9 for the jacks 6 and 7, respectively.
9 through the branch point 23, a large amount of oil flows to the side where the load is small due to the nature of the hydraulic pressure.
The left and right lifting jacks 6 and 7 have a stroke difference.

The present invention has been made in view of the above problems, and has as its object the purpose of making it possible to make the strokes of the right and left lifting jacks coincide with each other, and to assemble the surface of the grip segment with one ring already assembled. An object of the present invention is to provide a shielded excavator erector device that can easily meet the surface of the existing segment that has been finished with the surface of the ring adjacent to the ring currently assembled.

[0015]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention makes it possible to pivot around the central axis of the excavator body on the inner peripheral surface of the skin plate at the tail portion of the excavator body. A slewing ring mounted, an arm mounted on the slewing ring via left and right elevating devices to enable reciprocation of the slewing ring in a radial direction, and a segment gripping mechanism mounted on the arm via a posture control mechanism. In the electrifier of a shielded excavator, the lifting jack of each of the lifting devices is a double rod type, and a compression port of one of the lifting jacks and an extension port of the other lifting jack are connected to an oil passage. Are linked by

[0016]

The erector device of the shield excavator according to the present invention is constructed as described above, and switches the electromagnetic switching valve provided in the hydraulic circuit between the power unit and each of the lifting jacks to change the pressure discharged from the power unit. The oil is sent from the solenoid-operated switching valve to the extension port of one of the right and left lifting jacks and then to the extension pressure chamber of the lifting jack, and the two rod type pistons of the lifting jack are moved in the extension direction. In addition, the hydraulic oil in the compression side pressure chamber of the same lifting jack is sent to the compression side port → oil passage → expansion port of the other lifting jack → expansion side pressure chamber of the same lifting jack, and both rod type pistons of the same lifting jack Is moved in the extension direction. In addition, the hydraulic oil in the compression side pressure chamber of the lifting jack is returned from the electromagnetic switching valve to the oil tank.

[0017]

【Example】

(Embodiment 1) Next, a description will be given of an elector apparatus of a shield excavator according to the present invention with reference to a first embodiment shown in FIG. 1. Reference numeral 1 denotes a power unit, 2 denotes an oil tank, and 3 denotes a relief valve. 6 and 7 are lifting jacks having pistons of both rod types; 6d and 7d are pistons of lifting jacks 6 and 7 having both rod types; and 4 are hydraulic circuits between the power unit 1 and the lifting jacks 6 and 7. Mounted electromagnetic switching valves, 4a and 4b are coils of the electromagnetic switching valve 4, 9 is an extension port of the lifting jacks 6 and 7, 8 is a compression port of the lifting jacks 6 and 7, and 11 is a left-side telescopic jack. An oil passage connecting the extension side port 9 of 6 and the contraction side port 8 of the right elastic jack 7, a switching valve 13 for right and left operation of the lifting jack, and a switching valve 14 for left operation of the lifting jack left alone.

Next, the operation of the erector device of the shield excavator shown in FIG. 1 will be specifically described. When the arm 5 is moved radially outward, the coil 4 of the electromagnetic switching valve 4
b, the spool of the electromagnetic switching valve 4 is moved to the right, and the pressure oil from the power unit 1 is supplied to the electromagnetic switching valve 4 → the extension port 9 of the right-side telescopic jack 7 → the extension side of the right-side telescopic jack 7. The piston 7 of the right-side telescopic jack 7 leads to the pressure chamber.
d is moved downward (radially outward).

The hydraulic oil in the contraction side pressure chamber of the right-side telescopic jack 7 is supplied to the oil passage 11 → the extension port 9 of the left-side telescopic jack 6 →
The arm 5 is guided radially outward by moving the piston 6d of the left elastic jack 6 downward (radially outward) to the extension side pressure chamber of the left elastic jack 6. Further, the hydraulic oil in the compression side pressure chamber of the left telescopic jack 6 is supplied to the electromagnetic switching valve 4.
→ Return to oil tank 2.

In this case, the hydraulic circuit is a closed circuit, and the pistons 6d, 7d of the telescopic jacks 6, 7 are both rod type, so that the right and left lifting jacks 6, 7 move completely synchronously. When the arm 5 is moved inward in the radial direction, the coil 4a of the electromagnetic switching valve 4 is excited, the spool of the electromagnetic switching valve 4 is moved to the left, and the flow of the pressure oil is reversed. The retractable jacks 6, 7 are synchronously operated in the contraction direction.

Thus, the left and right lifting jacks 6, 7 are:
It operates synchronously, so if the oil leaks during the adjustment of the hydraulic circuit piping or the initial adjustment of the hydraulic circuit and the stroke of the left and right lifting jacks 6 and 7 shifts, It works synchronously. For this reason, it is necessary to move the left and right lifting jacks 6 and 7 to the contraction limit and perform an operation for reducing the stroke to eliminate the displacement.

In this case, the switching valve 13 for right and left operation of the lifting / lowering jack is excited in the opening direction, and the left and right retractable jack 6 is excited.
While the compression side port 8 and the expansion side port 9 are communicated by the switching valve 13, the coil 4 a of the electromagnetic switching valve 4 is excited.
Then, the pressures of the expansion-side pressure chamber and the contraction-side pressure chamber of the left elastic jack 6 become the same, so that the lifting jack 6 does not operate, and only the right lifting jack 7 contracts.

Further, the switching valve 14 for operating the lifting jack left alone.
In the opening direction, the contraction side port 8 and the extension side port 9 of the right elastic jack 7 are communicated by the switching valve 14, while the coil 4 b of the electromagnetic switching valve 4 is excited. Then, the pressures of the expansion-side pressure chamber and the contraction-side pressure chamber of the right-side elastic jack 7 become the same, and the up-and-down jack 7 does not operate, and only the left-side up / down jack 6 contracts.

By operating the switching valves 13 and 14, the left and right lifting jacks 6 and 7 can be operated independently, and by performing this operation, the stroke of the left and right lifting jacks 6 and 7 is shifted. To eliminate. (Embodiment 2) Next, a description will be given of an erector device for a shield excavator according to the present invention with reference to a second embodiment shown in FIGS. In this embodiment, the inner cylinder 21 of FIG. 5 is diverted to the jacks 6 and 7, so that the hydraulic jack is not required. That is, reference numeral 6 denotes a left-hand telescopic jack, 6a denotes a cylinder corresponding to the inner cylinder, 6b denotes a cylinder head, 6c denotes a piston rod, 6d denotes a piston, 6e denotes a packing, and a lower end of the piston rod 6c is attached to the arm 5.

Next, the operation of the erector device of the shield excavator shown in FIGS. When an attempt to move the arm 5 radially outwardly, the load of the left and right lift jacks 6, 7 and F _L, F _R. Solenoid switching valve 4
The solenoid 4b is excited to move the spool of the electromagnetic switching valve 4 to the right, and the hydraulic oil discharged from the power unit 1 is discharged from the electromagnetic switching valve 4 to the right-hand side of the extension port 9 of the lifting jack 7 at the right side.
Led to increases the hydraulic pressure P _R of the extension side pressure chamber of the lifting jacks 7.

[0026] The hydraulic P _R is higher than the pressure P ₀ of the contraction side pressure chamber (oil passage 11) of the right lift jacks 7 (P
_R > P ₀ ), oil of volume Q enters the right-side up / down jack 7 from the extension side port 9 and the piston of the right-side up / down jack 7 moves downward. The piston of the right-side up / down jack 7 (and the left-side up / down jack 6) is a double rod type.
→ The oil of the same volume Q is discharged to the oil passage 11, which is further extended into the extension side port 9 of the lifting jack 6 on the left side → into the extension pressure chamber of the lifting jack 6 and the piston of the lifting jack 6 on the left side is lowered. Then, the oil in the compression side pressure chamber of the lifting jack 6 on the left side is discharged by the same volume Q from the electromagnetic switching valve 4 to the oil tank 2. That is, the hydraulic circuits of the lifting jacks 6 and 7 are completely closed circuits.
The same volume Q of oil is supplied and discharged, and the lifting jacks 6, 7 operate accurately with the same stroke.

Further different load F _L, F _R of the left and right lifting jacks 6, description will be given of a case where load imbalance occurs. Assuming that the effective area of the pistons of the lifting jacks 6 and 7 is S, the thrust of the lifting jack 7 on the right side is S
× (P _R −P ₀ ), and the thrust of the lifting jack 6 on the left side is S × (P ₀ −P _L ). P _L is, since direct access to the oil tank 2 is very low pressures.

[0028] or the discharge pressure of Pawayunitsuto 1 is low, or if the load is large, between _{F L> S × (P 0} -P L) is thrust to the left of the lifting jacks 6 are lost to the load F _L gone, because the jacks does not move, it becomes P _R = P _0, the thrust of the right-hand side of the lifting jacks 7 becomes zero, all of P _R is consumed in the thrust of the left side of the lifting jacks 6. Now F
When becomes _{L = S × (P 0 -P} L), the same thrust of the left lifting jacks 6 and the load, but when you Ugokidaso is jacks, if not the pressure of P _R is sufficiently, ie, F _It is possible to move while _R > S × (P _R −P ₀ ).

That is, if the set pressure of the relief valve 3 and the capacity of the power unit 1 are sufficient for the load, the jacking operating pressures (P _R -P ₀ ) and (P ₀ -P _L ) become equal to the load F.
_The jitter moves while the values are balanced between _L and F _R. By utilizing this manner the characteristics of the hydraulic balance load F _L, even if there is imbalance in F _R, the pressure P ₀ and the pressure P _R, while changes to a value corresponding to the load, the left and right telescopic jacks 6, 7 will be extended. Since the pistons of the left and right elastic jacks 6 and 7 are both rod types, the expansion and contraction are exactly the same.

[0030]

As described above, the erector device of the shield excavator of the present invention switches the electromagnetic switching valve provided in the hydraulic circuit between the power unit and each of the lifting jacks to electromagnetically discharge the pressure oil discharged from the power unit. The switching valve → one of the left and right elevating jacks at the extension port of the elevating jack → sends to the elongating pressure chamber of the elevating jack, and moves both rod type pistons of the elevating jack in the extension direction. Also, send the hydraulic oil in the compression side pressure chamber of the same lifting jack to the compression side port → oil passage → extension port of the other lifting jack → extension side pressure chamber of the same lifting jack,
The two rod type pistons of the lifting jack are moved in the extending direction. Also, since the hydraulic oil in the compression side pressure chamber of the lifting jack is returned from the electromagnetic switching valve to the oil tank, the strokes of the left and right lifting jacks can be matched, and the surface of the grip segment has already been assembled into one ring. The surface of the existing segment and the surface of the ring adjacent to the ring currently assembled can be easily aligned.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram showing a first embodiment of an erector device of a shield excavator according to the present invention.

FIG. 2 is a front view showing a second embodiment of the erector device.

FIG. 3 is an explanatory diagram of an operation of the elector device.

FIG. 4 is a perspective view illustrating a conventional shielded excavator erector device.

FIG. 5 is an enlarged vertical sectional side view showing a lifting jack portion of the elector device.

FIG. 6 is a hydraulic circuit diagram of the erector device.

FIG. 7 is a hydraulic circuit diagram showing another example of the conventional elector device.

FIG. 8 is an explanatory diagram showing a coordinate system at the time of assembling a segment.

FIG. 9 is an explanatory diagram of the reason why a stroke difference occurs between left and right lifting jacks.

[Explanation of symbols]

 Reference Signs List 5 Arm 6, 7 Left and right lifting jacks 6d, 7d Both rod-type pistons 8 Retraction port 9 Expansion port 11 Oil path 14 Slewing ring 17 Segment gripping mechanism 18 Attitude control mechanism

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Noriomi Yahara 1-25-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Taisei Corporation (58) Field surveyed (Int.Cl. ⁶ , DB name) E21D 11/40

Claims (1)

(57) [Claims] 1. A swing ring attached to an inner peripheral surface of a skin plate at a tail portion of an excavator body so as to be able to swing about a central axis of the excavator body, and the swing ring is connected to the swing ring via left and right elevating devices. In an elector apparatus of a shield excavator having an arm attached to the revolving ring so as to be capable of reciprocating in a radial direction and a segment gripping mechanism attached to the arm via a posture control mechanism, the lifting jack of each of the lifting devices is An elector device for a shield excavator, wherein a piston is a double rod type, and a compression port of one of the lifting jacks and an expansion port of the other lifting jack are connected by an oil passage.