JPH0657992U - Propulsion jack spreader - Google Patents

Abstract

(57) [Abstract] [Purpose] The spreader can be pressed without separating from the segment centroid when promoting shield,
The propelling jack spreader will not cause buckling of the segment. [Structure] A spreader that is provided at the tip of a propulsion jack disposed between a shield excavator and a segment tip surface and presses the segment tip surface. A knuckle head fixed to the tip of the jack is formed by a fan-shaped flat plate, and the tip surface of the fan-shaped knuckle head is formed into a spherical surface, and the spreader plate directly contacting the segment receives the tip surface of the fan-shaped knuckle head. Fix the knuckle holder with the seat. The fan-shaped knuckle head and the knuckle receiver are spherically joined, and the spherical center of the spherical surface at the tip of the fan-shaped knuckle head is set on a plane including the center line of the propulsion jack rod.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a propulsion jack spreader, and relates to an improvement of a spreader for pressing a front end surface of a segment to propel a shield excavator.

[0002]

[Prior art]

 In general, a propulsion jack 1 used in a shield excavator has a cylinder portion 4 attached to a partition wall portion 3 in a shield body 2 and a jack rod 5 inserted therein, as shown in FIG. The rod 5 can be projected toward the front end face of the segment constructed behind the shield body 2. The propulsion jack 1 is arranged along the inner wall surface of the shield main body 2, while the segment is formed to have substantially the same diameter as the shield main body 2. Therefore, the center of extrusion of the propulsion jack 1 and the pressure receiving surface centroid of the segment coincide with each other. Since it is not offset, a spreader 6 is provided at the tip of the propulsion jack 1.

As shown in detail in FIG. 4, a conventional spreader 6 is provided with a spherical knuckle 8 offset to a fixing plate 7 on the tip surface of the jack rod 5, and a spreader plate 9 serving as an abutting member to the segment. A knuckle receiver 10 having a spherical bearing seat is provided on each of them, and both are configured as a spherical joint. As a result, the spreader plate 9 can be swung and rotated, and the spreader plate 9 can be properly aligned with the arc tip end surface of the segment.

[0004]

[Problems to be solved by the device]

 However, in the conventional spreader, the outer diameter dimension of the spreader plate 9 is affected by the size of the spherical joint including the spherical knuckle 8, and when a large propulsive force is transmitted, the pressing center of the spherical joint and the segment end surface are attempted. There was a drawback that the eccentricity with the centroid became large. For this reason, buckling occurs in the steel segment and peeling off of the corners occurs in the concrete segment.

The present invention focuses on the above-mentioned conventional problems, and the spreader can be pressed without separating from the centroid of the segment when the shield is propelled, so that the buckling of the segment does not occur. The purpose is to provide a structured jack jack spreader.

[0006]

[Means for Solving the Problems]

 In order to achieve the above object, the propulsion jack spreader according to the present invention is a spreader that is provided at the tip of the propulsion jack arranged between the shield excavator and the segment tip surface and presses the segment tip surface. The knuckle head fixed to the tip of the jack is formed by a fan-shaped flat plate and the tip surface of this fan-shaped knuckle head is formed into a spherical surface, and the spreader plate directly contacting the segment receives the tip surface of the fan-shaped knuckle head. A knuckle receiver provided with a spherical seat is fixed, the fan-shaped knuckle head and the knuckle receiver are spherically joined, and the spherical center of the tip spherical surface of the fan-shaped knuckle head is set on a plane including the propelling jack rod center line. It is a thing.

[0007]

[Action]

 According to the above configuration, the knuckle head is formed into a fan-shaped flat plate, and the knuckle receiver having a spherical seat for receiving the knuckle head is fixed to the spreader plate, so that the segment pressing surface of the spreader matches the segment end surface width and the segment It is possible to match the centroid with the center of pressure. Then, the propulsive reaction force from the spherical seat is transmitted through the knuckle head, but since this concentrated load point is transferred to the plane including the central axis of the jack rod, buckling of the knuckle head itself is prevented. It is possible. Moreover, since the center of the segment pressing action by the spreader can be made to coincide with the segment centroid, problems such as segment buckling and corner chipping can be solved. Further, since the knuckle head is a fan-shaped flat plate, it is possible to easily manufacture a spreader made of a thick iron plate without forming it into a spherical shape as in the past.

[0008]

【Example】

 Hereinafter, a specific embodiment of the propulsion jack spreader according to the present invention will be described in detail with reference to the drawings.

FIG. 1A is a sectional view of the propulsion jack spreader according to the first embodiment, and FIG. 1B is a partial sectional view as seen from the knuckle head side. The upper half is a conventional spreader and the lower is a spreader. Half is a comparative sectional view showing the structure of the embodiment. As shown in the figure, the spreader 20 according to the embodiment is attached to the tip end portion of the jack rod 22, and the spreader plate 24 that presses the end surface of the segment (not shown) is arranged at the tip end portion. The outer edge of the spreader plate 24 is formed in an arc shape so as to fit the flange surface of the segment, and the spreader plate 24 is surface-bonded to the flange of the segment to be pressed.

The spreader plate 24 is capable of spherical movement so as to always be properly face-to-face joined to the segment flange at the time of excavation of a curve or the like. This is due to the knuckle head 26 provided on the jack rod 22 side and the spreader plate 24 side. They are connected by a spherical joint with an attached knuckle receiver 28. The knuckle head 26 is attached to the tip of the jack rod 22 via a retainer 30, and the knuckle receiver 28 is formed in the center of the rear surface of the spreader plate 24 by a holding bracket 32 so as to be surrounded by an accommodation space 38. Held in. In addition, as shown in Fig. 1 (2), since the mounting position of the propulsion jack and the segment flange of the propulsion bearing surface are different from the center of the shield, the distance L is offset from the center of the jack. The knuckle head 26 needs to be arranged. The retainer 30 is used to fix the offset knuckle head 26 to the jack rod 22.

Here, the knuckle head 26 in the embodiment is a flat plate body formed by cutting out a thick plate member, and its planar shape is a so-called mushroom cross-sectional shape including a mounting base portion 26A for the retainer 30 side and a fan-shaped head 26B. It is shaped like a fan. The knuckle receiver 28 is also a flat plate body formed by cutting out a thick plate member having substantially the same thickness as the knuckle head 26, and is provided with a cutout concave portion 34 in which a portion corresponding to the fan-shaped head 26B is cut out. These both join the tip end surface of the fan-shaped head 26B and the inner peripheral surface of the cutout recess 34 to each other, and the joining surface is processed into a spherical surface so that spherical movement can be performed here. Then, as shown in FIG. 1 (1), the spherical center O of this joint surface is located at a position deviated from the knuckle head 26 when viewed from a plane cross section, and on a plane including the central axis of the jack rod 22. It is set to exist. As a result, the reaction force collecting load due to the operation of the propulsion jack acts on the ball center O on the jack rod 22 side, and the evenly distributed load from the joint surface is transmitted to the rod 22 side, and thus the knuckle head 26 and the knuckle head. It is possible to reduce the thickness of the receiver 28 and the width of the spreader plate 24.

A pressing plate 36 is provided to prevent the knuckle head 26 from coming off the knuckle receiver 28, and an elastic member 38 such as rubber is provided between the pressing plate 36 and the back surface of the fan-shaped head 26.

According to such an embodiment, since the knuckle head 26 and the knuckle receiver 28 are thinly formed to have a sectoral flat plate spherical joint structure, the center of the segment flange pressed by the spreader plate 24 is the centroid of the segment flange. Can match. As a result, shielded propulsion is possible without causing problems such as buckling of segments or chipping of corners. Moreover, the propulsive force becomes a uniformly distributed load, which acts on the spherical center O on the center line of the jack rod 22, so that the reaction force can be satisfactorily transmitted to the jack side and the spreader strength can be increased.

Next, FIG. 2 shows a second embodiment. This is to extend the lengths of the knuckle head 40 and the knuckle receiver 42 so that the knuckle head 40 and the knuckle receiver 42 can be applied to a medium to large diameter shield excavator, and set the spherical contact radius of these to be long. According to this structure, the area of the spherical joint increases, the pressing portion to the segment flange coincides with the centroid of the segment flange, and a larger load can be supported because of the uniformly distributed load method.

[0015]

[Effect of device]

 As described above, according to the present invention, the spreader is provided at the tip of the propulsion jack disposed between the shield excavator and the segment tip surface and presses the segment tip surface, and is fixed to the jack tip. The knuckle head is formed of a fan-shaped flat plate, and the tip surface of the fan-shaped knuckle head is formed into a spherical surface.The spreader plate that directly contacts the segment has a spherical seat that receives the tip surface of the fan-shaped knuckle head. The provided knuckle receiver is fixed, the fan-shaped knuckle head and the knuckle receiver are spherically joined, and the spherical center of the spherical surface at the tip of the fan-shaped knuckle head is set on a plane including the propelling jack rod center line, so that the shield is promoted. At this time, the spreader can be pressed without separating from the centroid of the segment, which causes buckling of the segment. Can be a propulsion jack spreader never cause.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a propulsion jack spreader according to a first embodiment and a cross-sectional comparison view of essential parts.

FIG. 2 is a cross-sectional view of a propulsion jack spreader according to a second embodiment and a cross-sectional comparison view of essential parts.

FIG. 3 is an overall configuration diagram of a conventional propulsion jack spreader.

FIG. 4 is a vertical and horizontal sectional view of a conventional spreader.

[Explanation of symbols]

 20 spreader 22 jack rod 24 spreader plate 26 knuckle head 28 knuckle receiver 30 retainer 32 retaining bracket 34 cutout recess 36 retainer plate 38 elastic member

Claims (1)

[Scope of utility model registration request] 1. A spreader which is provided at the tip of a propulsion jack disposed between a shield excavator and a segment tip surface and presses the segment tip surface, wherein a knuckle head fixed to the jack tip is formed by a fan-shaped flat plate. While forming, the tip surface of this fan-shaped knuckle head is formed into a spherical surface,
A knuckle receiver provided with a spherical seat for receiving the tip end surface of the fan-shaped knuckle head is fixed to the spreader plate directly contacting the segment, and the fan-shaped knuckle head and the knuckle receiver are spherically joined and the tip of the fan-shaped knuckle head is fixed. A propulsion jack spreader in which the spherical center of the sphere is set on a plane including the propulsion jack rod center line.