A drill rod centralizing device for a mixing pile

Abstract

The present application provides a drilling pipe righting device for mixing piles, belonging to the technical field of pile construction machinery. The drilling pipe righting device for mixing piles comprises: an upper righting structure, comprising a bushing pair and a guide seat, the bushing pair is used for sleeving on the outside of the drilling pipe, the bushing is installed on the guide seat, and the guide seat is used for driving the bushing to synchronously ascend and descend with the drilling pipe; a lower righting structure, comprising an annular guide rail, a sliding seat, a limiting wheel row and a mounting seat, the annular guide rail is fixedly installed on the mounting seat, the mounting seat is used for fixing the annular guide rail at a predetermined height, a plurality of sliding seats are centrally symmetrically arranged on the annular guide rail, and the limiting wheel row is longitudinally rotatably installed on the sliding seat; the sliding seat is located in the inner ring of the annular guide rail, the limiting wheel row forms a passage for the drilling pipe to pass downward in a vertical state, and the limiting wheel row is clamped on the surface of the drilling pipe. The present application has the advantages of good drilling pipe righting effect, convenient drilling pipe centering, improved drilling precision and better protection of the drilling pipe.

Description

Technical Field

[0001] This invention relates to the field of piling machinery technology, specifically to a drill rod straightening device for mixing piles. Background Technology

[0002] The mixing pile method is a pile foundation construction method that combines air jetting and grouting. During construction, the verticality of the drill rod not only directly affects whether the hole quality meets the process requirements, but also provides excellent protection for the drill rod, preventing bending, breakage, and safety accidents during operation. Therefore, a drill rod straightening device is installed on the pile driver column to guide and support the drill rod to maintain its verticality. However, current drill rod straightening devices are follow-up straightening devices that rise and fall synchronously with the drill rod. They are usually located at or near the top of the drill rod. During drilling, the bottom of the drill rod still lacks guidance and support. When the drill rod comes into contact with hard objects such as rocks in the soil, it is easily impacted and squeezed, causing disturbance. This disturbance poses a greater risk, especially when the drill rod is long. Summary of the Invention

[0003] To solve the above-mentioned technical problems, the present invention proposes a drill rod straightening device for mixing piles.

[0004] The technical solution of this invention is implemented as follows:

[0005] A drill rod straightening device for a mixing pile includes:

[0006] The upper straightening structure includes a bushing assembly and a guide seat. The bushing assembly is used to be sleeved on the outside of the drill pipe, and the bushing is installed on the guide seat. The guide seat is used to drive the bushing to move up and down synchronously with the drill pipe.

[0007] The lower straightening structure includes an annular guide rail, a slide block, a row of limiting wheels, and a mounting base. The annular guide rail is fixedly mounted on the mounting base, which is used to fix the annular guide rail at a predetermined height. Multiple slide blocks are centrally symmetrically arranged on the annular guide rail. The row of limiting wheels is rotatably mounted on the slide block in the longitudinal direction.

[0008] The slide block is located on the inner ring of the annular guide rail. When the limiting wheel row is in a vertical state, it forms a channel for the drill rod to pass through downwards, and the limiting wheel row is clamped on the surface of the drill rod.

[0009] Furthermore, the upper and lower end faces and the middle of the annular guide rail are provided with annular track grooves, and the upper and lower end faces and the middle of the outer side of the slide are provided with track wheels. Adjacent slides are connected by an arc plate, and the arc plate is located in the annular track groove in the middle.

[0010] Furthermore, the limiting wheel row includes a wheel mounting plate, transverse wheels, supports, and mounting shafts. The inner side of the wheel mounting plate has a groove, and the transverse wheels are installed in the groove at equal intervals. The supports are fixedly installed on the outer side of the wheel mounting plate, and the mounting shafts are fixedly installed on the outer end of the supports. The slide has a mounting groove, and the supports are disposed in the mounting groove. Both sides of the mounting groove are provided with shaft holes, and the mounting shafts are disposed in the shaft holes.

[0011] Furthermore, the inner side of the slide includes an arc-shaped surface and a vertical surface distributed vertically. The arc-shaped surface is centered on the mounting shaft. When the limiting wheel row is in a vertical state, the outer side of the wheel mounting plate contacts the vertical surface. When the limiting wheel row rotates about the mounting shaft, the outer side of the wheel mounting plate is displaced on the arc-shaped surface.

[0012] Furthermore, a rod sleeve is rotatably provided on the top of the slide block, and an upper rotating rod is provided inside the rod sleeve. An upper outer tension spring is provided between the two ends of the upper rotating rod and the inner side of the wheel mounting plate. The outer tension spring causes the limiting wheel row to be in a state where the top end is tilted outward in the initial state.

[0013] Furthermore, when the limiting wheel row is in its initial state, the boundary of the channel is located inside the mounting shaft.

[0014] Furthermore, the wheel mounting plate includes an upper plate and a lower plate. The support is fixedly mounted on the outer side of the upper plate, and the support is located between the two ends of the upper plate in the length direction of the upper plate. The lower plate is slidably mounted on the upper plate in the inward and outward directions. An inward spring is provided between the lower plate and the slide block. The inward spring causes the lower plate to be offset inward relative to the upper plate in the initial state, and the distance by which the lower plate is offset inward relative to the upper plate is less than the radius of the transverse wheel.

[0015] Furthermore, sliding grooves are provided on both sides of the upper plate, and a sliding plate whose bottom end is connected to the top end of the lower plate is slidably disposed in the sliding groove. A "U"-shaped connecting plate is fixedly disposed on the outer side of the sliding plate. The two parallel sides of the connecting plate pass through the outer inner wall of the sliding groove, and the two connecting plates are connected by a limiting plate. The limiting plate is located on the outer side of the upper plate. A through groove is provided on the support, and the limiting plate passes through the through groove. The inner end of the inner push spring is connected to the connecting plate. A lower rotating rod is rotatably mounted on the slide. The center of the lower rotating rod is at the same height as the mounting shaft, and the lower rotating rod is located on the outer side of the mounting shaft. The outer end of the inner push spring is connected to the lower rotating rod.

[0016] Furthermore, an arc-shaped groove for displacement of the limiting plate is provided on the arc-shaped surface, and a limiting groove for the limiting plate to enter is provided at the bottom end of the arc-shaped groove. When the limiting wheel row is in a vertical state, the limiting plate is located at the opening of the limiting groove, and the inner push spring is in a horizontal state.

[0017] Furthermore, upper shovel plates are provided on both sides of the upper plate, and a lower shovel plate is provided at the bottom of the lower plate. When the limiting wheel row is in a vertical state, the two upper shovel plates located between two adjacent limiting wheel rows are in contact on opposite sides.

[0018] The present invention has the following beneficial effects:

[0019] 1. By setting up upper and lower straightening structures, the upper and lower ends of the drill rod are synchronously guided and supported, improving the drill rod's anti-disturbance performance, better protecting the drill rod, and improving drilling accuracy.

[0020] 2. By directly aligning the lower straightening structure with the drilling position, and with both the upper and lower straightening structures installed on the column of the mixing pile machine, the alignment of the upper straightening structure with the drilling position can be achieved directly and synchronously, which has the advantage of facilitating the alignment of the drill rod with the drilling position.

[0021] 3. By setting up upper and lower shovel plates, during the reciprocating drilling and grouting process, when the drill rod rises, the upper and lower shovel plates can remove impurities such as grout, soil, and gravel from the surface of the drill rod, preventing the drill rod from carrying impurities into the space between the transverse wheel and the drill rod, thereby improving the straightening effect of the drill rod and reducing wear. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the state when the drill rod has not passed through the lower straightening structure in this invention;

[0023] Figure 2 This is the present invention. Figure 1 Enlarged view of part A in the image;

[0024] Figure 3 This is the present invention. Figure 1 Enlarged view of part B in the image;

[0025] Figure 4 This is the present invention. Figure 1 A schematic diagram of the state of the lower straightening structure in the middle;

[0026] Figure 5 This is a schematic diagram of the present invention when the drill rod does not pass through the limiting wheel row and the limiting wheel row is in a vertical state;

[0027] Figure 6 This is the present invention. Figure 5 Enlarged view of section C in the image;

[0028] Figure 7 This is the present invention. Figure 5 A schematic diagram of the state of the lower straightening structure in the middle;

[0029] Figure 8 This is the present invention. Figure 7 Enlarged view of part D in the image;

[0030] Figure 9 This is a schematic diagram showing the state of the drill pipe passing through the lower straightening structure in this invention;

[0031] Figure 10 This is the present invention. Figure 9 Enlarged view of part E in the image;

[0032] Figure 11 This is the present invention. Figure 9 A schematic diagram of the state of the lower straightening structure in the middle;

[0033] Figure 12 This is the present invention. Figure 11 Enlarged view of part F in the image;

[0034] Figure 13 This is a schematic diagram of the arc-shaped plate of the present invention;

[0035] Figure 14 This is the present invention. Figure 4 A schematic diagram of the middle limit wheel arrangement;

[0036] Figure 15 This is the present invention. Figure 14 A schematic diagram showing the disassembly of the middle limit wheel assembly;

[0037] Figure 16 This is the present invention. Figure 15 Another perspective view.

[0038] In the diagram: Bushing pair 1, Guide seat 2, Drill rod 3, Annular guide rail 4, Slide seat 5, Arc surface 5-1, Vertical surface 5-2, Limiting wheel row 6, Horizontal wheel 6-1, Support 6-2, Mounting shaft 6-3, Mounting groove 6-4, Shaft hole 6-5, Upper plate 6-6, Lower plate 6-7, Mounting seat 7, Annular track groove 8, Track wheel 9, Arc plate 10, Rod sleeve 11, Upper rotating rod 12, Outer tension spring 13, Inner push spring 14, Sliding groove 15, Slide plate 16, Connecting plate 17, Limiting plate 18, Through groove 19, Lower rotating rod 20, Arc groove 21, Limiting groove 22, Upper shovel plate 23, Lower shovel plate 24. Detailed Implementation

[0039] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0040] like Figures 1 to 16 As shown, the drill rod straightening device for mixing piles provided in this embodiment of the invention includes:

[0041] The upper straightening structure includes a bushing assembly 1 and a guide seat 2. The bushing assembly 1 is used to be sleeved on the outside of the drill rod 3. The bushing is installed on the guide seat 2. The guide seat 2 is used to drive the bushing to rise and fall synchronously with the drill rod 3. The guide seat 2 is installed on the column of the mixing pile machine.

[0042] The lower straightening structure includes an annular guide rail 4, a sliding block 5, a limit wheel row 6, and a mounting base 7. The annular guide rail 4 is fixedly installed on the mounting base 7, which is used to fix the annular guide rail 4 at a predetermined height. The mounting base 7 is installed on the column of the mixing pile machine. Multiple sliding blocks 5 are centrally symmetrically arranged on the annular guide rail 4. The limit wheel row 6 is rotatably installed on the sliding block 5 in the longitudinal direction.

[0043] The slide block 5 is located on the inner ring of the annular guide rail 4. When the limit wheel row 6 is in a vertical state, it forms a channel for the drill rod 3 to pass through downwards, and the limit wheel row 6 is clamped on the surface of the drill rod 3.

[0044] In practice, by adjusting the pile driver column and aligning the lower straightening structure with the drilling position, the upper straightening structure can also be aligned with the drilling position. When the drill rod 3 enters the lower straightening structure and passes through the channel, on the one hand, the drill rod 3 is aligned vertically and with the drilling position through the correction at both ends. On the other hand, during the reciprocating drilling process, the upper straightening structure moves up and down synchronously with the drill rod 3 to guide and support the top of the drill rod 3, while the lower straightening structure guides and supports the lower part of the drill rod 3. This greatly improves the stability of the drill rod 3 in maintaining a vertical drilling state during operation, reduces the disturbance of the drill rod 3, improves the drilling progress, and prevents the drill rod 3 from swinging, bending, or breaking, thus extending the service life of the drill rod 3.

[0045] The annular guide rail 4 has annular grooves 8 on its upper and lower ends and in its middle. Track wheels 9 are installed on the upper and lower ends and in the middle of the outer side of the slide block 5. Adjacent slide blocks 5 are connected by an arc-shaped plate 10, which is located within the annular groove 8 in the middle. The arc-shaped plate 10 connects all the slide blocks 5 into one unit, ensuring that the relative position and distance between adjacent slide blocks 5 remain constant. The cooperation of the track wheels 9 and the annular grooves 8 provides three-point support and guidance for the slide blocks 5 in the height direction, greatly improving the stability of the slide blocks 5. Especially during the rotation of the drill rod 3, the slide blocks 5, through the rolling of the track wheels 9 within the annular guide rail 4, maintain the same rotational state as the drill rod 3.

[0046] The limiting wheel assembly 6 includes a wheel mounting plate, transverse wheels 6-1, supports 6-2, and mounting shafts 6-3. The inner side of the wheel mounting plate has a groove, and the transverse wheels 6-1 are installed in the groove at equal intervals. The supports 6-2 are fixedly installed on the outer side of the wheel mounting plate, and the mounting shafts 6-3 are fixedly installed on the outer end of the supports 6-2. The slide block 5 has a mounting groove 6-4, and the supports 6-2 are located within the mounting groove 6-4. Both sides of the mounting groove 6-4 have shaft holes 6-5, and the mounting shafts 6-3 are located within the shaft holes 6-5. The transverse wheels 6-1 contact the surface of the drill rod 3, clamping and limiting the drill rod 3. Simultaneously, the rotation of the transverse wheels 6-1 facilitates the lifting and lowering movement of the drill rod 3.

[0047] The inner surface of the slide block 5 includes an arc-shaped surface 5-1 and a vertical surface 5-2 distributed vertically. The arc-shaped surface 5-1 is centered on the mounting shaft 6-3. When the limiting wheel row 6 is in a vertical position, the outer surface of the wheel mounting plate contacts the vertical surface 5-2. When the limiting wheel row 6 rotates around the mounting shaft 6-3, the outer surface of the wheel mounting plate displaces on the arc-shaped surface 5-1. When the limiting wheel row 6 is in a vertical position, the vertical surface 5-2 contacts the outer surface of the wheel mounting plate, thus limiting and supporting the limiting wheel row 6 from the outside, improving the limiting and supporting effect of the limiting wheel row 6 on the drill rod 3.

[0048] A rod sleeve 11 is rotatably mounted on the top of the slide block 5. An upper rotating rod 12 is housed within the rod sleeve 11. Upper outer tension springs 13 are positioned between the two ends of the upper rotating rod 12 and the inner surface of the wheel mounting plate. The outer tension springs 13 cause the limiting wheel row 6 to initially tilt outwards at its top. Specifically, as the bottom end of the drill rod 3 passes through the lower straightening structure from top to bottom, the limiting wheel row 6, under the pressure of the drill rod 3, rotates around the mounting shaft 6-3. The upper rotating rod 12 rotates inwards, and the outer tension springs 13 are stretched inwards. Simultaneously, during the rotation of the limiting wheel row 6, the arc-shaped surface 5-1 supports the outer surface of the wheel mounting plate. At this time, the arc-shaped surface 5-1, in conjunction with the mounting shaft 6-3, simultaneously supports the limiting wheel row 6, improving its stability and compressive strength.

[0049] More specifically, in its initial state, the boundary of the channel of the limiting wheel row 6 is located inside the mounting shaft 6-3. This configuration ensures that the limiting wheel row 6 can be pressed down and rotated inward by the drill rod 3.

[0050] Wherein, the wheel mounting plate comprises an upper plate portion 6-6 and a lower plate portion 6-7, the support 6-2 is fixedly mounted on the outer side surface of the upper plate portion 6-6, the support 6-2 is located between two ends of the upper plate portion 6-6 in the length direction of the upper plate portion 6-6, the lower plate portion 6-7 is slidably mounted on the upper plate portion 6-6 in the inner-outer direction, an inward pushing spring 14 is disposed between the lower plate portion 6-7 and the sliding seat 5, the inward pushing spring 14 enables the lower plate portion 6-7 to be in an inwardly offset state relative to the upper plate portion 6-6 in an initial state, and the inward offset distance of the lower plate portion 6-7 relative to the upper plate portion 6-6 is smaller than the radius of the transverse wheel 6-1.

[0051] Specifically, in this embodiment, when the bottom end of the drill pipe 3 presses down the limiting wheel row 6, the bottom end edge of the drill pipe 3 contacts the top of the uppermost transverse wheel 6-1 in the lower plate portion 6-7. Then, after the limiting wheel row 6 is pressed down by the drill pipe 3 and switched from an inclined state to a vertical state, with the continuous descending of the drill pipe 3, the drill pipe 3 applies pressure to the uppermost transverse wheel 6-1 on the lower plate portion 6-7, the lower plate portion 6-7 displaces outward on the upper plate portion 6-6 and compresses the inward pushing spring 14. At this time, when the limiting wheel row 6 is set to be in the vertical state, there is a gap between the transverse wheel 6-1 in the upper plate portion 6-6 and the surface of the drill pipe 3, the transverse wheel 6-1 on the lower plate portion 6-7 is relied on to limit and support the drill pipe 3, in this way, the elastic force of the inward pushing spring 14 is used to provide a certain buffering performance.

[0052] Sliding grooves 15 are provided on both sides of the upper plate portion 6-6, sliding plates 16 with bottom ends connected to the top end of the lower plate portion 6-7 are slidably disposed in the sliding grooves 15, a -shaped connecting plate 17 is fixedly disposed on the outer side surface of the sliding plate 16, two parallel sides of the connecting plate 17 penetrate through the outer inner wall surface of the sliding groove 15, the two connecting plates 17 are connected by a limiting plate 18, the limiting plate 18 is located on the outer side of the upper plate portion 6-6, a through slot 19 is opened on the support 6-2, the limiting plate 18 penetrates through the through slot 19, the inner end of the inward pushing spring 14 is connected to the connecting plate 17, a lower rotating rod 20 is rotatably mounted on the sliding seat 5, the center of the lower rotating rod 20 and the center of the mounting shaft 6-3 are at the same height, the lower rotating rod 20 is located on the outer side of the mounting shaft 6-3, and the outer end of the inward pushing spring 14 is connected to the lower rotating rod 20.

[0053] Specifically, when the lower plate portion 6-7 displaces on the upper plate portion 6-6, the limiting plate 18 displaces in the through slot 19, and the connecting plate 17 displaces on the upper plate portion 6-6, by utilizing the guiding effect of the through slot 19 on the limiting plate 18, the guiding effect of the upper plate portion 6-6 on the connecting plate 17 and the guiding effect of the sliding groove 15 on the sliding plate 16, the suspension and guiding effect of the upper plate portion 6-6 on the lower plate portion 6-7 can be improved, ensuring that the lower plate portion 6-7 stably displaces on the upper plate portion 6-6.

[0054] An arc-shaped groove 21 for the displacement of the limiting plate 18 is provided on the arc-shaped surface 5-1. A limiting groove 22 for the limiting plate 18 to enter is provided outward at the bottom end of the arc-shaped groove 21. When the limiting wheel row 6 is in a vertical state, the limiting plate 18 is located at the opening of the limiting groove 22, and the inner push spring 14 is in a horizontal state. Specifically, when the limiting wheel row 6 is in an inclined state, the limiting plate 18 is located in the arc-shaped groove 21, and the top of the limiting plate 18 is in contact with the inner wall of the top of the arc-shaped groove 21. At this time, by using the limiting of the limiting plate 18 by the arc-shaped groove 21 and the pulling force of the outer pull spring 13 on the wheel mounting plate, all the limiting wheel rows 6 can be in the same inclined angle. When the lower plate 6-7 is displaced outward on the upper plate 6-6 by the force of the drill rod 3, the limiting plate 18 enters the limiting groove 22. At this time, the limiting groove 22 limits the limiting plate 18, thereby locking the limiting plate 18 in the height direction. This ensures that the limiting wheel row 6 can be stably kept in a vertical state during the raising and lowering of the drill rod 3, and has a stable guiding and supporting effect on the drill rod 3.

[0055] During the process of drill rod 3 rising and disengaging from the limiting wheel row 6, at the instant drill rod 3 leaves the uppermost transverse wheel 6-1 inside the lower plate 6-7, the lower plate 6-7 is displaced outward under the action of the inner push spring 14, and the limiting plate 18 disengages from the limiting groove 22. During the process of drill rod 3 disengaging from the transverse wheel 6-1 inside the upper plate 6-6, the limiting wheel row 6 as a whole is reset to its tilted state under the action of the outer pull spring 13.

[0056] Upper shovel plates 23 are provided on both sides of the upper plate 6-6, and lower shovel plates 24 are provided at the bottom of the lower plate 6-7. When the limiting wheel row 6 is in a vertical state, the two upper shovel plates 23 located between two adjacent limiting wheel rows 6 contact each other on opposite sides. Specifically, the portion of the upper shovel plate 23 connecting to the side of the upper plate 6-6 extends downward to the junction of the upper plate 6-6 and the lower plate 6-7, and blocks the gap between the side of the upper plate 6-6 and the drill rod 3. At this time, during the reciprocating drilling and grouting process of the drill rod 3, when the drill rod 3 rises, the upper shovel plates 23 and lower shovel plates 24 can remove residual grout, soil, gravel and other impurities from the surface of the drill rod 3 downward, effectively cleaning the surface of the drill rod 3, preventing debris from entering between the drill rod 3 and the transverse wheel 6-1 and interfering with the effective cooperation between the transverse wheel 6-1 and the drill rod 3, and reducing the wear of both.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A drill rod straightening device for a mixing pile, characterized in that, include: The upper straightening structure includes a bushing pair (1) and a guide seat (2). The bushing pair (1) is used to be sleeved on the outside of the drill rod (3). The bushing is installed on the guide seat (2). The guide seat (2) is used to drive the bushing to move up and down synchronously with the drill rod (3). The lower straightening structure includes an annular guide rail (4), a slide block (5), a limit wheel row (6), and a mounting base (7). The annular guide rail (4) is fixedly mounted on the mounting base (7). The mounting base (7) is used to fix the annular guide rail (4) at a predetermined height. Multiple slide blocks (5) are centrally symmetrically arranged on the annular guide rail (4). The limit wheel row (6) is rotatably mounted on the slide block (5) in the longitudinal direction. The slide block (5) is located on the inner ring of the annular guide rail (4). When the limiting wheel row (6) is in a vertical state, it forms a channel for the drill rod (3) to pass through downwards, and the limiting wheel row (6) is clamped on the surface of the drill rod (3). The limiting wheel row (6) includes a wheel mounting plate, a transverse wheel (6-1), a support (6-2), and a mounting shaft (6-3). The inner side of the wheel mounting plate is provided with a groove, and the transverse wheels (6-1) are installed in the groove at equal intervals. The support (6-2) is fixedly installed on the outer side of the wheel mounting plate, and the mounting shaft (6-3) is fixedly installed on the outer end of the support (6-2). The slide (5) is provided with a mounting groove (6-4), and the support (6-2) is located in the mounting groove (6-4). Both sides of the mounting groove (6-4) are provided with shaft holes (6-5), and the mounting shaft (6-3) is located in the shaft holes (6-5). The inner side of the slide (5) includes an arc-shaped surface (5-1) and a vertical surface (5-2) distributed vertically. The arc-shaped surface (5-1) is centered on the mounting shaft (6-3). When the limiting wheel row (6) is in a vertical state, the outer side of the wheel mounting plate is in contact with the vertical surface (5-2). When the limiting wheel row (6) rotates about the mounting shaft (6-3), the outer side of the wheel mounting plate is displaced on the arc-shaped surface (5-1). The top of the slide block (5) is rotatably provided with a rod sleeve (11), and an upper rotating rod (12) is provided inside the rod sleeve (11). An upper outer tension spring (13) is provided between the two ends of the upper rotating rod (12) and the inner side of the wheel mounting plate. The outer tension spring (13) causes the limiting wheel row (6) to be in a state where the top is tilted outward in the initial state. The wheel mounting plate includes an upper plate (6-6) and a lower plate (6-7). The support (6-2) is fixedly installed on the outer side of the upper plate (6-6), and the support (6-2) is located between the two ends of the upper plate (6-6) in the length direction of the upper plate (6-6). The lower plate (6-7) is slidably installed on the upper plate (6-6) in the inward and outward directions. An inward spring (14) is provided between the lower plate (6-7) and the slide (5). The inward spring (14) causes the lower plate (6-7) to be offset inward relative to the upper plate (6-6) in the initial state, and the distance by which the lower plate (6-7) is offset inward relative to the upper plate (6-6) is less than the radius of the transverse wheel (6-1). The upper plate (6-6) is provided with upper shovel plates (23) on both sides, and the lower plate (6-7) is provided with a lower shovel plate (24) at the bottom end. When the limiting wheel row (6) is in a vertical state, the two upper shovel plates (23) located between two adjacent limiting wheel rows (6) are in contact on opposite sides.

2. The drill rod straightening device for a mixing pile according to claim 1, characterized in that, The upper and lower end faces and the middle of the annular guide rail (4) are provided with annular track grooves (8). The upper and lower end faces and the middle of the outer side of the slide (5) are provided with track wheels (9). Two adjacent slides (5) are connected by an arc plate (10), and the arc plate (10) is located in the annular track groove (8) in the middle.

3. The drill rod straightening device for a mixing pile according to claim 1, characterized in that, In the initial state, the boundary of the channel of the limiting wheel row (6) is located inside the mounting shaft (6-3).

4. The drill rod straightening device for a mixing pile according to claim 1, characterized in that, Both sides of the upper plate (6-6) are provided with sliding grooves (15). A sliding plate (16) with its bottom end connected to the top end of the lower plate (6-7) is slidably disposed in the sliding groove (15). A "U"-shaped connecting plate (17) is fixedly disposed on the outer side of the sliding plate (16). The two parallel sides of the connecting plate (17) pass through the outer inner wall of the sliding groove (15), and the two connecting plates (17) are connected by a limiting plate (18). The limiting plate (18) is located on the upper plate (6-6). On the outside, the support (6-2) has a through groove (19), the limiting plate (18) passes through the through groove (19), the inner end of the inner push spring (14) is connected to the connecting plate (17), the slide (5) is rotatably mounted with a lower rotating rod (20), the lower rotating rod (20) is at the same height as the center of the mounting shaft (6-3), and the lower rotating rod (20) is located outside the mounting shaft (6-3), the outer end of the inner push spring (14) is connected to the lower rotating rod (20).

5. The drill rod straightening device for a mixing pile according to claim 4, characterized in that, The arc-shaped surface (5-1) is provided with an arc-shaped groove (21) for displacement of the limiting plate (18). The bottom end of the arc-shaped groove (21) is provided with a limiting groove (22) for the limiting plate (18) to enter. When the limiting wheel row (6) is in a vertical state, the limiting plate (18) is located at the opening of the limiting groove (22), and the inner push spring (14) is in a horizontal state.

Images