Pin rod anti-falling structure of down-the-hole drill

Abstract

The utility model provides a kind of pin bar anti-drop structure of down-the-hole drill, including sleeve, sleeve middle part position is equipped with second annular groove, second annular groove side is equipped with pin hole, pin hole is movably inserted with pin bar, both ends of pin bar are located in pin hole, the utility model further includes the sheath matched with second annular groove, sheath is movably sleeved on second annular groove, and sheath limits pin bar in pin hole.The pin bar anti-drop structure proposed by the utility model reduces the difficulty of pipe shoe machining in reality, and makes the installation and disassembly of pipe shoe and drill bit more convenient, that is, when installing, only need to insert pin bar first, then sheath can be put on;When disassembling, only need to take down sheath, and pin bar can be ejected with pointed tool.

Description

Technical Field

[0001] This utility model relates to the field of down-the-hole drill bit technology, specifically to a pin anti-detachment structure for down-the-hole drill bits. Background Technology

[0002] The shoe of a down-the-hole drill is a key component used to stabilize the hole wall, guide the drill bit, and protect the drill string during the drilling process. It mainly plays a supporting and guiding role, and is also a key part of the connection with the drill pipe.

[0003] Down-the-hole drills are divided into pin-type and other types. For example... Figure 4 The drill bit shown is a pin-type down-the-hole drill, whose most important feature is the presence of a movable pin groove on the side of the drill shank (e.g., Figure 4 (As indicated by the middle arrow C), after the tube shoe is fitted onto the drill shank, a pin is provided in the pin hole at point B on the side of the tube shoe. The pin is placed in the movable pin groove, so that the drill bit can move radially along the tube shoe. Currently, the pin is fixed at the top of the boot (e.g., Figure 4 Drill a hole (pointed to by the middle arrow A) that connects to the movable pin slot. Connect a pin to the hole with a spring. The pin extends into the pin hole under the action of the spring to fix the pin and prevent it from coming out of the pin hole.

[0004] This fixing method has obvious drawbacks. When removing the pin, a sharp tool is needed to first lift the pin, and then another sharp tool is needed to push the pin out from the other end of the pin hole, making the operation cumbersome. From a manufacturing perspective... Figure 4 The hole indicated by the middle arrow A is deep and difficult to machine, and the internal spring further complicates the structure. Therefore, we propose a pin-locking structure for down-the-hole drill bits. Utility Model Content

[0005] This invention provides a pin anti-detachment structure for down-the-hole drill bits, which has the advantage of easy installation and solves the problems mentioned in the background art.

[0006] The technical solution of this utility model is implemented as follows: a pin anti-dislodgement structure for down-the-hole drill bit is designed, including a sleeve, a second annular groove is provided in the middle of the sleeve, a pin hole is provided on the side of the second annular groove, a pin is movably inserted in the pin hole, and both ends of the pin are located in the pin hole. This utility model also includes a protective sleeve that matches the second annular groove. The protective sleeve is movably fitted on the second annular groove, and the protective sleeve limits the pin to be in the pin hole.

[0007] Preferably, the upper step of the second annular groove is provided with a first annular groove, and the surface of the first annular groove is provided with external threads.

[0008] Preferably, the inner wall of the sleeve is provided with multiple keyways.

[0009] Preferably, the top of the sheath is provided with an annular pad, the inner diameter of which matches the inner diameter of the first annular groove. When the annular pad is fitted onto the first annular groove, the edge of the annular pad is positioned on the top of the sheath.

[0010] Compared with the prior art, the pin anti-detachment structure proposed in this utility model reduces the processing difficulty of the pipe shoe in reality, and makes the installation and disassembly of the pipe shoe and drill bit more convenient. That is, when installing, you only need to insert the pin first and then put on the protective sleeve; when disassembling, you only need to remove the protective sleeve and push the pin out with a pointed tool. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of the explosive structure of this utility model.

[0013] Figure 2 This is a schematic diagram of the structure of the present invention and the drill pipe. Figure 1 .

[0014] Figure 3 This is a schematic diagram of the structure of the present invention and the drill pipe. Figure 2 .

[0015] Figure 4 This is a schematic diagram of the existing pipe shoe and drill bit.

[0016] In the diagram: 1. Sleeve; 2. Pin hole; 3. Second annular groove; 4. Key bar; 5. Sheath; 6. Pin bar; 7. First annular groove; 8. Annular gasket. Detailed Implementation

[0017] The technical solution of this utility model will be clearly and completely described below with reference to its embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0018] Reference Figures 1 to 3 This utility model provides a technical solution: a pin anti-detachment structure for a down-the-hole drill bit, including a sleeve 1, which, like the existing tube shoe, is fitted onto the drill bit.

[0019] A second annular groove 3 is provided in the middle of the casing 1, and a first annular groove 7 is provided above the second annular groove 3 via a stepped surface. The surface of the first annular groove 7 is provided with an external thread, which is used for connecting with the drill pipe (such as...). Figure 2 Connected to the middle arrow D), the inner wall of the sleeve 1 is provided with multiple key bars 4, which match the keyways on the drill bit shank. When the sleeve 1 is fitted, the key bars 4 are placed in the keyways.

[0020] The improvement in this application lies in omitting... Figure 4 The hole indicated by the middle arrow A is missing, while only the pin hole on the side of the boot is retained. For example... Figure 1 As shown, the second annular groove 3 has a pin hole 2 on its side. The position of the pin hole 2 corresponds to the groove on the surface of the drill shank. A pin rod 6 is movably inserted into the pin hole 2. When the pin rod 6 is fully inserted into the pin hole 2, both ends of the pin rod 6 are located inside the pin hole 2. After the sleeve 1 is put on the drill shank, the pin 6 is also in the preset position. In order to prevent the pin 6 from coming out, a protective sleeve 5 is put on the second annular groove 3. The size of the protective sleeve 5 matches the second annular groove 3. When the protective sleeve 5 is moved on the second annular groove 3, the protective sleeve 5 limits the pin 6 in the pin hole 2. No matter how the pin 6 moves in the pin hole 2, both ends of it will be blocked by the protective sleeve 5 and will not come out of the pin hole 2.

[0021] Based on the above embodiments, the advantage of using the sheath 5 and the limiting pin 6 is that: firstly, it eliminates the step of machining the hole (e.g., Figure 4 (As indicated by the middle arrow A), it reduces the difficulty of tube shoe processing; secondly, it is more convenient to install and disassemble. When installing, you only need to insert the pin 6 first and then put on the protective sleeve 5. When disassembling, you only need to remove the protective sleeve 5 and push out the pin 6 with a pointed tool. It should be noted that the top height of the sheath 5 is at most flush with the bottom of the first annular groove 7. In this way, when the casing 1 is connected to the drill pipe threaded hook, the sheath 5 can be limited by the bottom of the drill pipe to prevent the sheath 5 from falling off.

[0022] Based on the above embodiments, it should be further explained that in reality, there is a problem where the pipe shoe is thicker than the drill pipe. In this case, the drill pipe cannot limit the movement of the sheath 5. Therefore, an annular washer 8 is needed. During use, the annular washer 8 is first fitted onto the first annular groove 7. For example... Figure 3 As shown, at this time, the top of the sheath 5 is provided with an annular pad 8. The inner diameter of the annular pad 8 matches the inner diameter of the first annular groove 7. When the annular pad 8 is fitted onto the first annular groove 7, the edge of the annular pad 8 is placed on the top of the sheath 5, and the annular pad 8 is pressed by the bottom of the drill rod, so that the annular pad 8 limits the position of the sheath 5.

[0023] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A pin anti-detachment structure for a down-the-hole drill bit, comprising a sleeve (1), characterized in that, The sleeve (1) has a second annular groove (3) in the middle, and a pin hole (2) is provided on the side of the second annular groove (3). A pin (6) is movably inserted in the pin hole (2), and both ends of the pin (6) are located in the pin hole (2). It also includes a sleeve (5) that matches the second annular groove (3), the sleeve (5) is movably fitted on the second annular groove (3), and the sleeve (5) limits the pin (6) in the pin hole (2).

2. The pin anti-detachment structure for down-the-hole drill bits as described in claim 1, characterized in that, The upper step of the second annular groove (3) is provided with a first annular groove (7), and the surface of the first annular groove (7) is provided with external threads.

3. The pin anti-detachment structure for down-the-hole drill bits as described in claim 2, characterized in that, Multiple keyways (4) are provided on the inner wall of the sleeve (1).

4. The pin anti-detachment structure for down-the-hole drill bit as described in claim 2, characterized in that, The top of the sheath (5) is provided with an annular pad (8). The inner diameter of the annular pad (8) matches the inner diameter of the first annular groove (7). When the annular pad (8) is fitted onto the first annular groove (7), the edge of the annular pad (8) is placed on the top of the sheath (5).

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