A foam hole protection device

Abstract

The present invention relates to a foam hole protection device, comprising a protection cap, the bottom of which is fixedly connected to a protection plate, the bottom of which is fixedly connected to a cutter disc at the periphery of the foam hole, and the peripheral size of the protection cap is larger than the peripheral size of the protection plate; a flow guide port is provided on the side of the protection plate away from the middle of the cutter disc. The foam hole protection device of the present invention can provide multi-directional protection for the foam hole to prevent soil from blocking the foam hole: 1) the protection cap covers the foam hole, and during excavation, the soil cannot directly enter the foam hole from a direction perpendicular to the cutter disc; 2) the flow guide port is provided on a side away from the middle of the cutter disc, which is consistent with the flow direction of the soil, and can effectively prevent the soil from entering the foam hole from the flow guide port.

Description

Technical Field

[0001] The invention relates to the technical field of shield machine cutter discs, and in particular to a foam hole protection device. Background Art

[0002] The cutterhead of the earth pressure balance shield machine is provided with multiple foam holes. During excavation, foaming agent is injected from the foam holes into the space between the cutterhead and the tunnel face to improve the performance of the soil, ensure the fluidity of the soil, reduce the permeability of the soil, reduce the friction between the cutterhead and the soil, and reduce the adhesion between the cutterhead and the soil, which is conducive to excavation and can prevent the cutterhead from forming mud cakes, while also keeping the tunnel face stable.

[0003] Since the foam hole is opened on the cutter head, the working environment is poor. In order to prevent the excavated soil from blocking the foam hole, the technicians in this field installed a protective device 1 (such as Figure 1 As shown), this protective device 1 is in a straight line shape, and there are gaps on both sides of the protective device 1. When the cutter disc rotates, the excavated soil will diffuse from the center of the cutter disc to the surroundings, and the diffused soil will enter the foam holes from the gaps toward the center of the cutter disc, causing the foam holes to be blocked. Therefore, the protective effect of this protective device is not ideal. Summary of the invention

[0004] In view of the defects in the prior art, the technical problem to be solved by the present invention is to provide a foam hole protection device to protect the foam holes during the excavation process to prevent the soil from blocking the foam holes.

[0005] In order to solve the above technical problems, the present invention provides a foam hole protection device, including a protective cap, a protective plate fixedly connected to the bottom of the protective cap, the bottom of the protective plate fixedly connected to the knife disc at the periphery of the foam hole, and the outer peripheral size of the protective cap is larger than the outer peripheral size of the protective plate; a guide port is provided on the side of the protective plate away from the middle position of the knife disc.

[0006] When the foam hole protection device of the present invention is in use, the protection plate is welded to the cutter disc so that the protection plate surrounds the outer periphery of the foam hole, and only the protection cap can be seen from the direction perpendicular to the cutter disc but the foam hole cannot be seen, and the diversion port provided on the protection plate can facilitate the passage of foam. Generally speaking, the soil that blocks the foam hole usually includes two parts, one is the soil cut by the face directly entering the foam hole, and the other is the soil cut by the center roller gradually moves to the foam hole as the cutter disc rotates. The foam hole protection device of the present invention can provide multi-directional protection for the foam hole to prevent the soil from blocking the foam hole: 1) The protection cap covers the foam hole, and during excavation, the soil cannot directly enter the foam hole from the direction perpendicular to the cutter disc; 2) The diversion port is provided on the side away from the middle position of the cutter disc, which is consistent with the flow direction of the soil, and can effectively prevent the soil from entering the foam hole from the diversion port.

[0007] Preferably, the protective plate is in an arc shape, and the guide port is formed at its opening.

[0008] Preferably, the central angle of the protective plate is greater than 180° to further prevent soil from entering the foam holes from the diversion port.

[0009] Preferably, guide plates are provided on both sides of the guide port of the protective plate, the ends of the guide plates are fixedly connected to the outer wall of the protective plate, and the distance between the outer wall of the guide plate and the axis of the protective plate gradually increases in the direction away from the end of the guide plate. The setting of the guide plate can guide the soil passing through the foam hole protection device, change the flow direction of the soil, and make it move in the direction away from the guide port.

[0010] Preferably, the outer wall of the guide plate is planar and tangent to the outer wall of the protective plate. The friction between the planar guide plate and the soil is small, which prevents the soil from sticking to the guide plate and ensures the guide plate's function of guiding the soil.

[0011] Preferably, a boss is fixedly connected to the bottom of the protective cap, and the outer periphery of the boss is tightly fitted with the inner periphery of the protective plate; the bottom of the boss is an inclined surface, which gradually slopes downward in the direction away from the diversion port. The setting of the boss can guide the foam, so that the foam moves toward the diversion port, and the force exerted by the inclined surface on the foam can make the foam move in the direction of the tunnel face, which is conducive to the mixing of the foaming agent and the soil.

[0012] Preferably, the protective cap is in a cone shape with a small top and a large bottom. With this structure, the contact area between the protective cap and the tunnel face can be reduced. At the same time, the conical protective cap has a small resistance to the soil and does not hinder the flow of the soil.

[0013] Preferably, a plurality of wear-resistant strips are evenly distributed on the top circumference of the protective cap, and the wear-resistant strips are arranged along the generatrix direction of the protective cap to protect the protective cap and increase its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0015] Figure 1 It is a schematic diagram of the structure of a traditional foam hole protection device;

[0016] Figure 2It is a structural schematic diagram of a foam hole protection device according to an embodiment of the present invention;

[0017] Figure 3 for Figure 2 Bottom view of

[0018] Figure 4 A schematic diagram of the structure of a protective cap according to an embodiment of the present invention;

[0019] Figure 5 It is a schematic diagram of the installation of the foam hole protection device according to an embodiment of the present invention.

[0020] Reference numerals:

[0021] 1-protection device; 2-protection cap; 3-protection plate; 4-guide plate; 5-center hob;

[0022] 21-wear-resistant strip; 22-boss; 31-flow guide port. DETAILED DESCRIPTION

[0023] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0024] like Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, this embodiment discloses a foam hole protection device, including a conical protection cap 2, the bottom of which is fixedly connected to a protection plate 3, the outer circumferential dimension of the protection cap 2 is larger than the outer circumferential dimension of the protection plate 3, the bottom of the protection plate 3 is fixedly connected to the cutter disc, and the installed protection plate 3 surrounds the outer circumference of the foam hole.

[0025] Specifically, the protective plate 3 is in an arc shape, and its central angle is greater than 180°. The opening of the protective plate 3 forms a guide port 31, and the foaming agent can flow out from the guide port 31 to between the cutter head and the tunnel face. When installing, the guide port 31 of the protective plate 3 is set on the side away from the middle position of the cutter head. Figure 5 The diameter of the cutter disc is located on the symmetry plane of the guide port 31. The foam hole protection device of this embodiment is suitable for installation near the middle position of the cutter disc to ensure that the foam agent is in full contact with the soil. After installation, the protective cap 2 can prevent the soil from entering the foam hole from a direction perpendicular to the cutter disc, and the guide port 31 is arranged on the side of the protective plate 3 away from the middle position of the cutter disc, which can effectively prevent the soil excavated by the center roller 5 from entering the foam hole from the guide port 31, thereby realizing the protection function of the foam hole and effectively preventing the foam hole from being blocked.

[0026] In order to further prevent the soil moving along the cutter disc from entering the foam holes from the guide port 31, in this embodiment, guide plates 4 are provided on both sides of the guide port 31 of the above-mentioned protective plate 3, and the end of the guide plate 4 is fixedly connected to the outer wall of the protective plate 3, and the distance between the outer wall of the guide plate 4 and the axis of the protective plate 3 gradually increases in the direction away from the end of the guide plate 4. Then, the soil moving from the center of the cutter disc changes its flow direction under the action of the guide plate 4 and moves obliquely forward of the guide port 31, thereby further preventing the soil from entering the foam holes; in addition, the outer wall of the above-mentioned guide plate 4 is in a planar shape, and the outer wall of the guide plate 4 is tangent to the outer wall of the protective plate 3, so as to reduce the friction between the guide plate 4 and the soil and prevent the soil from sticking to the guide plate 4.

[0027] Specifically, the protective cap 2 is in the shape of a cone that is small at the top and large at the bottom, and a number of wear-resistant strips 21 are evenly distributed on the top circumference of the protective cap 2. The wear-resistant strips 21 are arranged along the generatrix direction of the protective cap 2. The conical structure can reduce the contact area between the protective cap 2 and the face of the tunnel. At the same time, the conical protective cap 2 has less resistance to the soil and does not hinder the flow of the soil. The arrangement of the wear-resistant strips 21 can extend the service life of the protective cap 2 and prevent it from wear.

[0028] Furthermore, a boss 22 is fixedly connected to the bottom of the protective cap 2, and the outer periphery of the boss 22 is tightly fitted with the inner periphery of the protective plate 3; the bottom of the boss 22 is an inclined surface, which gradually tilts downward in the direction away from the guide port 31 to guide the foam agent, so that the foam moves toward the guide port 31, and the force exerted on the foam by the bottom inclined surface of the boss 22 can make the foam move in the direction of the tunnel face, which is beneficial to the mixing of the foam agent and the soil.

[0029] In this embodiment, the above-mentioned fixed connection methods are preferably welding.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A foam hole protection device, characterized in that: include: A protective cap, the bottom of which is fixedly connected to a protective plate, the bottom of which is fixedly connected to a cutter disc at the periphery of the foam hole, and the outer circumference of the protective cap is larger than the outer circumference of the protective plate; A guide port is provided on one side of the protective plate away from the middle of the cutter disc; The protective plate is in an arc shape, and the opening thereof forms the guide port; Guide plates are provided on both sides of the guide port of the protective plate, the ends of the guide plates are fixedly connected to the outer wall of the protective plate, and the distance between the outer wall of the guide plate and the axis of the protective plate gradually increases in the direction away from the end of the guide plate; The protective cap is in a cone shape that is small at the top and large at the bottom.

2. A foam hole protection device according to claim 1, characterized in that: The central angle of the protective plate is greater than 180°.

3. A foam hole protection device according to claim 1, characterized in that: The outer wall of the guide plate is in a plane shape, and the outer wall of the guide plate is tangent to the outer wall of the protective plate.

4. A foam hole protection device according to claim 1, characterized in that: The bottom of the protective cap is fixedly connected with a boss, and the outer periphery of the boss is tightly fitted with the inner periphery of the protective plate; The bottom of the boss is in the form of an inclined surface, which gradually slopes downward in a direction away from the guide port.

5. The foam hole protection device according to claim 1, characterized in that: A plurality of wear-resistant strips are evenly distributed on the top circumference of the protective cap, and the wear-resistant strips are arranged along the generatrix direction of the protective cap.

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