JP3050027U - Weed excavator - Google Patents

Abstract

(57) [Summary] [Problem] To ensure that a worker can aim at only the root of a weed in a standing posture and remove the weed by a single operation without damaging the surrounding planting. SOLUTION: The weed excavation device includes a positioning bar 1.
2 and a plurality of claw blades 13a disposed therearound, a rotary blade body 6 for digging the weeds 5, and a spiral groove 8a formed on the surface to engage with an immovable screwing member to reduce axial displacement. A rotating shaft body 8 that can rotate with the rotation of the rotating shaft body, a coil spring that biases an end of the rotating shaft body to enable axial displacement, and a rotating shaft body 8 that stores the coil spring and is displaced in the axial direction. And a handle portion 1 attached to the cylinder body. When the handle 1 is pushed down, the coil spring contracts. When the rotating shaft 8 is displaced in the axial direction, the rotating shaft 8 rotates through the spiral groove 8a that meshes with the screwing member, and rotates the rotating blade facing the root of the plant to locally dig the root. be able to.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a weed excavation device, and more specifically, a method for excavating and removing weeds that grow during lawn and planting by one operation without disturbing the surrounding topsoil. The present invention relates to a weed removing device according to the present invention.

[0002]

[Prior art]

 As devices for removing weeds, there are a device that directly rents hands and a device that uses power such as an electric motor. For the former, there is an erecter with a fork-shaped claw or a rake-like reiki at the end of the handle, so that the work is performed as if crouched on the ground. The latter converts the rotating power into a rocking motion using an electric motor, etc., and removes the weeds by tilling the roots of the weeds with reiki attached to the tips of support bars, etc., so that the operation can be performed without bending the body. it can.

When removing weeds growing on a wide lawn, it is needless to say that the operation in the crouched posture not only increases the burden on the operator, but also significantly reduces the work efficiency. There have been many proposals using mechanical power to reduce the work, and one of them is a weeding machine described in Japanese Utility Model Laid-Open No. 7-34603. This is a movement that operates a hoe with the power of an electric motor.

[0004] However, in a large park or garden, it is not easy or almost impossible to supply power by turning an electric cord. In some cases, a generator is carried to drive an electric motor or a small engine, but it requires a great deal of work to prepare for work, and the equipment is extremely expensive and unavoidable.

[0005] Therefore, recently, a weed removing device capable of working without requiring power supply and without crouching on the ground surface has been proposed. For example, in Japanese Utility Model Laid-Open Publication No. 6-1, the rake at the tip of the support bar, which is moved using the wheel and protrudes forward of the wheel, is connected to the wheel via a handle or support bar provided at a high position. It describes a device for weeding by repeating the operation of tilting using the principle of leverage with a point as a fulcrum.

[0006]

[Problems to be solved by the invention]

 By the way, the most difficult task of digging weeds while standing upright is to remove only the weeds to be digged. First of all, when removing the target weeds, it is important to be able to remove the topsoil without excessive excavation. Second, is it possible to remove, for example, weeds with roots that grow together with the lawn without scarcely damaging the lawn? Another question is whether the device can be used for planting shrubs and weeds growing at the roots of standing trees.

[0007] While avoiding excessive oversoiling of the topsoil appears to be straightforward, any of the known devices listed above is not sufficient. Because the eyes are far from the surface of the ground, it may not be easy to expose the reiki for excavation to the root of the weeds.However, it is necessary to swing the support bar to which the reiki is attached. Therefore, when the Reiki is placed higher than the root of the weed, it is necessary to imagine the swing locus and aim at the root.

[0008] Therefore, a repetitive operation such as correcting the aim by trial and error is inevitable, and the topsoil around the weeds is also disturbed. Furthermore, whether the support bar is swung by the power of the electric motor or tilted by human power using the principle of leverage, is it difficult to change the excavating force depending on how the roots are stretched? The cause is also impossible. Of course, in the case of human power, even if it is based on the principle of leverage, the excavating reaction force is transmitted as an impact, causing pain to the operator.

[0009] By the way, when there are grasses or plants to be left around such as weeds mixed with lawns, it is desirable that the width of the reiki is narrow. However, even if weeds can be targeted only if the width is narrow, in the above example, it is necessary to repeatedly shake down the reiki, and it will take time and effort to remove one weed .

[0010] In addition, since each device has wheels and an oscillating arm, it is necessary to provide a space for arranging the device and enabling the oscillating operation. Weeds at the edges of trenches and ponds, as well as weeds growing on rough terrain, and in bushes and hedges, often cannot be removed.

The present invention has been made in view of the above problems, and its purpose is to ensure that the worker can aim at only the root of the weed while standing, and in principle, to operate the surrounding area with one operation. Weeds can be removed without damaging the planting, and a large space is not required around the weeds for digging and weeding, so operation is not affected by bushes or other overhanging foliage such as shrubs A weed digging device that realizes that it can be done and that it is possible to remove it while significantly reducing the burden on hands and arms with extremely simple operation by human power without the need for mechanical power. It is to be.

[0012]

[Means for Solving the Problems]

 INDUSTRIAL APPLICABILITY The present invention is applied to a weed excavation device which can insert a blade object from the ground surface, excavate grass roots and extract weeds. Referring to FIG. 1, a rotating blade body 6 that rotates to excavate weeds 5, a rotating shaft body 8 that extends continuously from the rotating blade body 6, A guide cylinder 9 for bearing to guide the axial displacement of the rotary shaft 8 while allowing the rotation thereof; an elastic member 10 for biasing the end of the rotating shaft 8 to enable the axial displacement (see FIG. 5). A cylindrical body 11 containing the elastic member and accommodating the rotating shaft body 8 displaced in the axial direction; and a handle 1 attached to the cylindrical body. The above-mentioned rotary blade body 6 is provided with a positioning bar 12 which is located at a central portion, extends in the axial direction of the rotary shaft body 8 and is inserted into topsoil, and a plurality of claw blades 13a arranged around the positioning bar. And a bit body 13. A spiral groove 8a is formed on the surface of the rotating shaft 8, and a screwing member 9A (see FIG. 5) is engaged in the spiral groove 8a in the guide cylinder 9 and does not displace in the axial direction. ) Is arranged.

A chuck 7 for holding the rotary blade 6 is provided between the rotary blade 6 and the rotary shaft 8 so as to be continuous with the rotary shaft 8. It is preferable that a holding bar 14 is provided on the opposite side of the positioning bar 12 so as to extend in the axial direction of the rotating shaft 8 and be held by the chuck portion 7.

As shown in FIGS. 3 and 4, the chuck portion 7 has an insertion hole 17A into which the holding bar 14 is inserted, and has a cutout groove 17b at an intermediate portion of the side wall to reach the insertion hole. A spring 18 comprising a body 17, a hook portion 18 a engaged with a notch groove 17 b of the inner cylindrical body, and a coil portion 18 b connected to the hook portion and surrounding the outer surface of the rotary shaft from the notch groove 17 b. A sleeve body 19 which is externally fitted to the inner cylinder body 17 from the rotary blade body side and covers the spring 18; and a coil body 18b is shrunk by the axial movement of the sleeve body 19 provided inside the sleeve body, thereby hooking up the coil part 18b. A pressing portion 20 for retracting the portion 18a from the fitting hole 17A, and a concave portion 14a for locking the hook portion 18a is formed in the holding bar 14 of the rotary shaft 6 at a position corresponding to the notch groove 17b. It is.

[0015]

[Effect of the invention]

 According to the present invention, the rotating shaft that is displaced in the axial direction is rotated through the spiral groove by the rotation driving mechanism that is configured by the handle portion that is depressed, the elastic member that contracts, and the screw member that meshes with the spiral groove. By rotating the blade, the rotating blade facing the root of the plant rotates and digs the root. Therefore, weeds can be removed by a single operation without damaging surrounding plants and the like, and at that time, it is possible to reliably excavate and raise even if the worker is standing.

Since the device is in the shape of a long and thin rod, it is not necessary to secure a wide space for digging and raising work around the weeds. It can be easily operated without being affected and at the edge of ditches and ponds. Of course, it is a very simple operation by human power without requiring mechanical power, and the burden on hands and arms is significantly reduced.

If the chuck portion is provided between the rotary blade body and the rotary shaft body, the rotary blade body can be exchanged, and a worn bit body can be replaced or a bit body having a different size can be used. Is also possible. If the chuck portion is composed of an inner cylinder, a spring and a sleeve, the rotary blade can be easily attached and detached.

[0018]

[Embodiment of the invention]

 Hereinafter, the weed excavator according to the present invention will be described in detail with reference to the drawings showing an embodiment thereof. FIG. 1 shows a mode of use of a device capable of inserting a blade object from the ground surface, digging up grass roots and extracting weeds. This device is composed of a handle portion 1 gripped by an operator, a long shaft portion 2 that extends downward in connection with the handle portion, and a blade object 3 that rotates at the tip of the shaft portion. It automatically rotates, and a plurality of claw blades 13a dig the root accordingly.

More specifically, the weed excavator 4 includes a rotary blade 6 that rotates to excavate the weed 5 and a chuck unit 7 that holds the rotary blade on the ground surface side. A rotary shaft 8 extending in tandem with the chuck portion and a guide tube 9 for bearing to guide the axial displacement of the rotary shaft while permitting rotation are formed at an intermediate portion. Then, an elastic member 10 (see FIG. 5) for urging the upper end of the rotating shaft body 8 to enable axial displacement, and a rotating shaft storing the elastic member and displacing in the axial direction. A cylinder body 11 for accommodating the body 8 and a handle portion 1 attached to the cylinder body are provided.

As shown in FIGS. 1 and 2, the rotary blade body 6 is located at the center and extends in the axial direction of the rotary shaft body 8 and is inserted into the top soil. A bit body 13 provided with a plurality of claw blades 13a disposed on the other end thereof, and a holding bar 14 which is located on the opposite side to the positioning bar 12 and extends in the axial direction of the rotary shaft body 8 and is gripped by the chuck portion 7. doing.

The positioning bar 12 of the rotary blade body 6 may be a single iron round bar having a function as a holding bar 14, as shown in FIG. 2C, for example. The side of the steel pipe may be cut off from the left and right in the shape of an arrowhead as shown in FIG. Therefore, when the bit body 13 is viewed from the front, two claw blades 13a, 13a are formed as shown in FIG. In order to fix the pipe constituting the bit body 13 to the positioning bar 12, a spacer 15 fitted to the pipe as shown in FIG. Is fixed by a set screw 16 or the like.

The bit body 13 does not have to be formed by cutting off a pipe in the shape of an arrowhead. In short, the bit body 13 only needs to rotate with the positioning bar at a position slightly spaced around the positioning bar 12. The number of the claw blades 13a may be three or more, and the shape and posture of the claw blades 13a can be appropriately selected so as to be suitable for root excavation. However, in any case, the spacing between the claw blades 13a is generally sufficient to be 2 cm to 4 cm, since they are arranged aiming at the hairline of the weed.

Since the position of the rotary blade 6 is determined by slightly inserting the tip of the positioning bar 12 into the ground surface, it is preferable that the diameter is about 5 mm and the tip is slightly sharpened. . The positioning bar 12 is fixed such that its tip protrudes by about 2 cm to 3 cm from the tip of each claw blade 13 a of the bit body 13.

In the example of FIG. 1, the worn nail blade 13 a and the rotating blade body 6 can be detached from the long shaft portion 2 in order to change the size. For this purpose, the holding bar 14 located on the extension of the positioning bar 12 is provided with a locking concave portion 14a for preventing unintentional removal from the chuck portion 7, as shown in FIG. Formed in In addition, a semi-cylindrical engagement projection 14b is provided at the upper end to prevent the positioning bar 12 from rotating in the chuck portion 7.

On the other hand, as shown in FIG. 3A, the chuck portion 7 includes an inner cylinder 17, a spring 18, and a cylindrical sleeve 19. The inner cylindrical body 17 has a fitting hole 17A into which the holding bar 14 is inserted as shown in FIG. 4, and a notch groove 17b reaching the fitting hole at a middle portion of the side wall as shown in FIG. . The spring 18 includes a hook portion 18a which is locked in the notch groove 17b of the inner cylinder, and a coil portion 18b which is continuous with the hook portion and surrounds the outer surface of the rotary shaft from the notch groove 17b. The sleeve body 19 is externally fitted to the inner cylindrical body 17 from the rotary blade body side and covers the spring 18. Inside the sleeve body 19, the coil portion 18b is slightly shrunk by axial movement, A pressing portion 20 for retracting the portion 18a from the fitting hole 17A is provided.

Since the holding bar 14 is inserted into the chuck portion 7 to chuck the rotary blade body 6, the concave portion 14 a formed in the holding bar 14 has the above-described notch groove as shown in FIG. The rotary blade 6 can be detached from the chuck 7 when the hook 18a is retracted in the notch 17b as shown in FIG. 3C. In addition, as shown in FIG. 4, a recess 17a is provided at the back of the fitting hole 17A so as to mesh with the engaging projection 14b of the holding bar 14, so that the rotation of the chuck 7 can be transmitted to the rotary blade 6 reliably. Is taken into account.

Incidentally, in the illustrated example, the pressing portion 20 is a collar independent of the sleeve 19, but the collar 20 may be formed integrally with the inner surface of the sleeve 19. The upper edge of the collar is always in contact with the lower end of the coil portion 18b as shown in FIGS. 3 (a) and 4 and when the worker pushes up the coil portion 18b by the raising operation of the sleeve member 19, the upper portion of FIG. The hook portion 18a located at the position of the two-dot chain line as shown in (b) and (c) rises as shown by the solid line. This movement is indicated by the displacement of the hook portion 18a at the position indicated by the solid line in FIG. 4 to the position indicated by the two-dot chain line. With such movement, the hook portion 18a is displaced laterally so as to be disengaged from the concave portion 14a in the notch groove 17b.

In FIG. 3A, a part of the collar 20 is notched because a straight portion 18c that connects the coil portion 18b and the hook portion 18a and a bent portion 18d at the tip of the hook portion 18a are formed. This is to avoid interference. Reference numeral 21 in the figure denotes a snap ring which prevents the sleeve body 19 urged by the spring 18 via the collar 20 from dropping from the inner cylindrical body 17.

A spiral groove 8a is formed on the surface of the rotating shaft 8 as shown in FIG. 1, and the spiral groove 8a is formed in the guide cylinder 9 as shown in FIG. A screw member 9A that does not displace in the axial direction is disposed. Rotation is applied to the rotating shaft 8 which is displaced in the axial direction by this screwing member, and the rotating force is transmitted to the rotating blade 6 via the chuck portion 7.

In order to enable the displacement of the rotary shaft 8, the lower portion of the long cylindrical body 11 that can accommodate the rotary shaft 8 is provided with a guide for the axial displacement of the rotary shaft 8. A guide cylinder 9 for stabilizing the rotation is provided. In this example, the guide tube portion 9 is integrated with the tube body portion 11, but it is also possible to adopt a configuration in which both are screwed and joined. A coil spring 10 is interposed in the cylinder body 11, and the lower end of the coil spring 10 presses the top of the rotating shaft 8. A guiding pipe for the coil spring may be arranged as a liner along the inner wall of the cylinder body 11. The guiding pipe and the above-described guide cylinder functioning as a bearing may be integrated.

The screwing member 9A is provided in the guide tube portion. In the example of FIG. 5A, the screw member 9A is a small block-like key fitted into a key groove 9a formed on the inner surface of the guide tube portion 9. I have. Therefore, the key holding plug 22 is screwed to the lower end of the guide tube 9 in order to prevent the key from falling off. When a bolt 23 that meshes with the spiral groove 8a is employed as shown in FIG. 4B instead of the key block, it is not necessary to use a member for preventing falling off except for locking the screw. In either case, when the rotating shaft 8 is displaced in the axial direction relatively to the screwing member 9A, the rotating shaft 8 always rotates.

The handle 1 is attached to the upper end of the cylinder body 11 as shown in FIG. 6, but since the upper end of the coil spring 10 interposed in the cylinder body 11 is pressed before the attachment, The plug 24 is screwed to the inner surface of the barrel 11. By doing so, the rotating shaft body 8 that is displaced in the axial direction is rotated by the rotating drive mechanism that includes the coil spring 10 that contracts when the handle portion 1 is pressed down and the screwing member 9A that meshes with the spiral groove 8a. Is rotated through the spiral groove 8a, and the rotary blade body 6 facing the root of the vegetation rotates to dig the root.

Such a weed digging device is usually operated while standing, and since a downward force is applied to the handle portion, the height of the handle portion increases from the belly to the waist. It is set to be around. In the digging operation, it is sufficient that the rotary blade 6 rotates 1.5 to 2 times. If the pushing stroke of the handle is about 15 cm, the pitch of the spiral groove 8 a of the rotary shaft 8 is 10 cm. It is good to keep it. In order to increase the number of rotations, it is, of course, necessary to reduce the pitch or lengthen the stroke. Is selected.

According to the weed digging device having such a configuration, the root of the weed can be digged reliably by a simple operation as follows. First, as shown in FIG. 1, the weed digging device 4 is brought close to the weed 5, and when the weed is tall, the weed is slightly tilted, and the tip of the positioning bar 12 of the rotary blade 6 is lightly pushed to the root. This operation is an operation of directly arranging the positioning bar 12 directly on the ground surface even if the position of the eye is high, and can be performed extremely easily.

When a light weight is applied to the gripped handle portion 1, the handle portion 1 is lowered by the weight. At this time, since the rotating shaft 8 does not largely move in the axial direction due to the grounding of the rotating blade 6, the coil spring 10 in the cylindrical body 11 is contracted by receiving a reaction force from the ground. Therefore, the screwing member 9A descends together with the guide cylinder 9, and the rotating shaft 8 rotates through the spiral groove 8a. For example, when the handle portion 1 is pushed down by about 15 cm, if the pitch of the spiral groove 8 a is 10 cm, the rotary blade body 6 moves through the chuck portion 1. Make 5 rotations.

Although the positioning bar 12 slightly enters the ground by this pushing-down operation, the claw blade 13 a of the bit body 13 also rotates while entering the topsoil and cuts out the root of the weed 5. The claw blade 13a locally loosens the soil and simultaneously separates the root from the soil. However, if the facing distance between the claw blades 13a is, for example, about 2 cm, only the root of the target weed is disturbed, and the root of the surrounding lawn or the like is not dug. By this operation, the roots extending to the front, back, left and right are also cut a little, and in the case of small weeds, the nail blades 13a that rotate in the opposite direction when releasing the force applied to the handle part 1 are scattered so as to be popped off the ground surface You.

The present weed digging and raising apparatus is intended for small weeds growing on lawns and gardens and weeds stuck to the ground surface. Since the soil is loosened, it can be easily pulled out by pulling the trunk. In each case, most of the roots can be pulled out to the ground, so the weed regeneration rate is much lower than that of a mowing device that cuts off the roots.

When the weeds are large, the long axis 2 is inclined as shown in FIG. 1, but when the weeds are small, the long axis may be set in the vertical posture. For example, for weeds that grow on the periphery of ditches and ponds, the posture can be appropriately selected and inserted. Even if there are undulations or irregularities on the surface of the ground, the bit body only contacts locally, so it is not affected at all. In addition, even when weeds are extracted from the bushes, the work can be performed from outside the bushes by inserting the long axis into the bushes. Therefore, the removal operation, for example, in a hedge, is also simplified.

[0039] Even a weed that grows at the root of a standing tree or shrub can target only the weed. Of course, even if the branches are overhanging or growing densely and intertwined in a complicated manner, the operation is the same as in a bush. In this way, even in places that are out of reach or in such a small space that instruments and devices cannot be carried in, they can be operated in principle without crouching. Lifting is performed only by pushing down the handle, and secondary operations such as prying and scooping, which increase the burden on the operator, are not required.

In the digging operation, one push operation is usually sufficient. The torque of the bit body 13 is determined by the magnitude of the elastic force applied to the coil spring 10. However, if the handle portion 1 is pressed quickly, the rotary blade body 6 can rotate at a high speed and bounce off the weeds. As a result, a large torque can be applied to the bit body 13. The operation may be appropriately performed in consideration of the tight roots of the weeds.

Of course, even when the coil spring 10 and other elastic members are employed, the excavating force increases if the preload is increased and a large force can be applied. When the nail blade 13a of the bit body 13 has an arrowhead shape as shown in FIG. 2B, the resistance from the soil applied to the tip is small, and the topsoil is loosened at the tip, so that the width is wide thereafter. Partial entry is also easy. Therefore, the force applied to the handle portion is reduced, and the feeling of fatigue and pain is significantly reduced.

In any case, the positioning bar 12 can be easily disposed by directly aiming at the root of the weed, and the positioning bar stabilizes the position of the bit 13 so that only the targeted weed can be easily obtained. It can be removed, and unnecessary operations that occur in the case of trial and error operations are avoided.

FIG. 5C shows an example in which a spring plate 25 is used as a screwing member. When the guide cylinder 9 is pushed down, it meshes with the spiral groove 8a and rotates the rotary shaft 8, but when the force is released from the handle and the coil spring 10 is restored, the leading end of the spring plate is restored. The spring plate can ride on the portion of the rotary shaft body 8 without the spiral groove 8a by the warped portion 25a. Therefore, when the rotating shaft 8 that has entered the cylindrical body 11 is pushed out, the rotating shaft 8 can be kept from rotating. For example, in the case of small weeds, the bit is dug by regular rotation of the bit. It is suitable for cases where the raising is sufficient and weeds are not scattered.

In the weed digging and raising apparatus described above, the chuck portion is provided in order to enable the wear and the size change of the bit body, but the gripping mechanism in the chuck portion is not limited to the illustrated example. May be used. Note that the rotary blade body can be directly connected to the rotary shaft body and integrated without providing the chuck portion.

In addition, the handle portion does not need to protrude left and right, but may be provided with a grip surrounding the upper end of the cylindrical body. One of the objects of the present invention is to be able to work without bending over the body. However, in the case of a person who does not feel a burden on such an operation or a person who can easily handle a short device, a T-shaped handle portion is used. It is not necessary to be.

[Brief description of the drawings]

FIG. 1 is an operation diagram showing a state immediately before starting a work in which a weed digging device according to the present invention is arranged at the base of a weed.

FIG. 2 is an example of a rotary blade body composed of a positioning bar also serving as a holding bar and a bit body, wherein (a) is a front view,
(B) is a side view, and (c) is a cross-sectional view.

FIG. 3 is a chuck section for gripping the rotary blade body,
(A) is a normal state diagram, (b) and (c) are front views and side views showing a state in which a sleeve body is pushed up to contract a spring and a hook portion is retracted in a notch groove.

FIG. 4 is a cross-sectional view showing a state where a rotary blade body is gripped by a chuck unit.

5A and 5B show a guide cylinder having a screw member and a part of a cylinder body connected to the guide cylinder. FIG. 5A is a cross-sectional view of an example in which a key block is used as the screw member, and FIG. FIG. 4C is a cross-sectional view of an example in which a bolt is used, and FIG. 4C is a cross-sectional view of an example in which a spring plate is used as a screwing member when the rotating shaft body is prevented from rotating when a force is released.

FIG. 6 is a cross-sectional view including a partially broken portion near a handle portion.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Handle part, 6 ... Rotary blade body, 7 ... Chuck part, 8 ...
Rotary shaft body, 8a: spiral groove, 9: guide cylinder part, 9A: screw member, 10: elastic member (coil spring), 11: cylinder body, 12: positioning bar, 13: bit body, 13a ...
Claw blade, 14 ... holding bar, 14a ... recess, 17 ... inner cylinder,
17A: fitting hole, 17b: notch groove, 18: spring, 18a: hook portion, 18b: coil portion, 19: sleeve body, 20: pressing portion (color).

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[Procedure amendment]

[Submission date] February 6, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims for utility model registration

[Correction method] Change

[Correction contents]

[Utility model registration claims]

Claims (3)

[Utility model registration claims] A weed excavator capable of inserting a blade object from the ground surface, excavating grass roots and extracting weeds, a rotating blade body rotating to excavate weeds. A rotary shaft body extending in tandem with the rotary blade body, a guide tube portion for bearing to allow rotation while guiding axial displacement of the rotary shaft body, and biasing an end of the rotary shaft body. An elastic member capable of axially displacing the elastic member, a cylindrical body storing the elastic member and accommodating the rotating shaft body displaced in the axial direction, and a handle attached to the cylindrical body. A bit provided with a positioning bar that is located at a central portion and extends in the axial direction of the rotary shaft body and is inserted into topsoil; and a bit provided with a plurality of claw blades disposed around the positioning bar. A spiral groove is formed on the surface of the rotating shaft body. And a screwing member that meshes with the spiral groove and is not displaced in the axial direction, is disposed in the guide cylinder. 2. A chuck portion for holding the rotary blade body is provided between the rotary blade body and the rotary shaft body so as to be continuous with the rotary shaft body. The weed digging device according to claim 1, further comprising a holding bar located on an opposite side and extending in an axial direction of the rotating shaft body and held by the chuck portion. 3. The inner cylindrical body having a fitting hole into which the holding bar is inserted and having a cutout groove at an intermediate portion of a side wall to reach the fitting hole. A spring formed of a hook portion locked in the notch groove and a coil portion connected to the hook portion and surrounding the outer surface of the rotary shaft body side from the notch groove, and a spring fitted to the inner cylinder body from the rotary blade body side; A sleeve body that covers a spring; and a pressing portion provided inside the sleeve body to retract the coil portion by the axial movement of the sleeve body to retract the hook portion from the fitting hole. The weed digging device according to claim 1 or 2, wherein the bar has a recess formed at a position corresponding to the notch groove to lock the hook portion.