Replacement method of hammer arm and hammer arm replacement jig

Abstract

To provide a replacement method of a hammer arm that enables a hammer arm pin to be easily detached from a plate in replacement of the hammer arm.SOLUTION: Provided is a replacement method of a hammer arm of a crusher including: a rotary shaft; a plurality of disc-shaped plates arrayed in an axial direction of the rotary shaft; and a plurality of hammer arms fixed to the plate via a hammer arm pin. The replacement method of the hammer arm includes: an impact application step of applying an impact to the hammer arm pin from a direction along an array direction of the plate; a removal step of removing the hammer arm engaged with the hammer arm pin by moving the hammer arm pin in the axial direction of the rotary shaft after the impact application step; an arrangement step of arranging a new hammer arm at a position of the removed hammer arm; and a fixation step of fixing the new hammer arm to the plate by using the hammer arm pin.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a method for replacing a hammer arm of a crusher and a jig for replacing a hammer arm.

Background Art

[0002] A crusher has a rotating shaft, a plurality of disk-shaped plates arranged in the axial direction of the rotating shaft, and a plurality of hammer arms fixed to the plates via hammer arm pins. The hammer arms strike the material to be crushed by the rotation of the rotating shaft. Therefore, the hammer arms are likely to be worn or damaged and are replaced at an appropriate time.

[0003] When replacing the hammer arms, the hammer arm pins are pulled out from the plates, the hammer arms are removed from the plates, new hammer arms are provided at the positions, and then fixed again with the hammer arm pins.

[0004] When replacing the hammer arms, it may be difficult to pull out the hammer arm pins. In response to such a problem, for example, the lower end of the hammer arm pin is pushed up by a pressing device and the hammer arm pin is pulled out upward (see Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, if the crushed powder enters the gap provided between the hammer arm pin and the members around it, the hammer arm pin may become stuck. In such a case, there is a problem that the hammer arm pin cannot be easily replaced even by using a pressing device such as a jack or a cylinder described in Patent Document 1.

[0007] The present invention has been made in view of the above problems, and an object thereof is to provide a method for replacing a hammer arm and the like that can easily remove the hammer arm pin from the plate when replacing the hammer arm.

Means for Solving the Problems

[0008] To solve the above problems, the present invention has the following features.

[0009] [1] A method for replacing a hammer arm of a crusher, comprising a rotating shaft, a plurality of disk-shaped plates arranged in the axial direction of the rotating shaft, and a plurality of hammer arms fixed to the plates via hammer arm pins, an impact applying step of applying an impact to the hammer arm pin from a direction along the arrangement direction of the plates; a removing step of moving the hammer arm pin in the axial direction of the rotating shaft after the impact applying step to remove the hammer arm engaged with the hammer arm pin; an arranging step of arranging a new hammer arm at the position of the removed hammer arm; a fixing step of fixing the new hammer arm to the plate using the hammer arm pin; A method for replacing a hammer arm, including the above steps. [2] In the removing step, among the plurality of hammer arm pins arranged in contact with each other in the axial direction of the rotating shaft, the hammer arm pin arranged at the axial end of the rotating shaft is moved. The method for replacing a hammer arm according to [1]. [3] In the impact application step, the impact is applied to at least one of the front and rear in the axial direction of the rotating shaft, the method for replacing the hammer arm according to [1] or [2]. [4] In the impact application step, the impact is applied to the rear in the axial direction of the rotating shaft, the method for replacing the hammer arm according to any one of [1] to [3]. [5] In the impact application step, among the plurality of hammer arm pins arranged in contact with each other in the axial direction of the rotating shaft, an impact is applied to the hammer arm pin arranged at the end in the axial direction of the rotating shaft, the method for replacing the hammer arm according to [3] or [4]. [6] A hammer arm replacement jig used for replacing the hammer arm of a crusher, having a rotating shaft, a plurality of disk-shaped plates arranged in the axial direction of the rotating shaft, and a plurality of hammer arms fixed to the plates via hammer arm pins. A mounting portion formed to be attachable to the hammer arm pin of the crusher. Following the mounting portion, it has a rod-shaped impact application portion that applies an axial impact to the mounting portion. The impact application portion includes a hammer portion slidably provided in a direction along the axial direction of the rotating shaft, and a stopper that regulates the sliding position of the hammer portion, the hammer arm replacement jig. [7] The mounting portion is formed to be detachable from the impact application portion and is formed according to the length from the hammer arm pin to be attached to one end in the axial direction of the rotating shaft, the hammer arm replacement jig according to [6]. [8] The stopper of the impact application portion is provided on the base end side away from the mounting portion in the axial direction, the hammer arm replacement jig according to [6] or [7].

Advantages of the Invention

[0010] According to the method for replacing the hammer arm of the present invention and the like, there are an impact applying step of applying an impact to the hammer arm pin from a direction along the arrangement direction of the plates, and a removing step of removing the hammer arm after the impact is applied to the hammer arm pin. Thereby, it becomes possible to remove crushed matter and the like located in the gap provided between the hammer arm pin and the members around it. Therefore, the operation of removing the hammer arm pin from the plate can be performed smoothly, and the hammer arm pin can be easily removed from the plate. As a result, it becomes possible to quickly replace the hammer arm.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows the configuration of a crusher. As shown in FIG. 1, the crusher 100 has a hammer unit 10 that rotates around the axis of the rotating shaft 11 and a housing 20 that covers the hammer unit 10.

[0013] The hammer unit 10 has a rotating shaft 11, a plate 12 attached to the rotating shaft 11, and a plurality of hammer arms 14 fixed to the plate 12 via hammer arm pins 13.

[0014] The rotating shaft 11 is a shaft formed in a cylindrical shape. The rotating shaft 11 is connected to a power unit (not shown) such as a motor so as to be rotatable about its axis.

[0015] The plate 12 is formed in a disc shape. Insertion holes (not shown) for inserting the hammer arm pins 13 are provided in the circumferential direction of the plate 12. The insertion holes are not particularly limited, but for example, 12 insertion holes are provided for one plate 12. In the present embodiment, the hammer arm pins 13 are inserted into all of these insertion holes.

[0016] The hammer arm 14 is formed in a columnar shape extending outward in the circumferential direction of the plate 12. A hammer head is provided on the tip side of the hammer arm 14. The hammer arm 14 and the hammer arm pin 13 are not particularly limited, but for example, 116 of them are provided for one crusher.

[0017] The housing 20 has an accommodation space 22 surrounded by a wall portion 21. The hammer unit 10 is accommodated in the accommodation space 22. The housing 20 is provided with an inlet 23 for introducing a crushing object above the accommodation space 22. The housing 20 is provided with an outlet 24 for discharging the crushed material obtained by crushing the crushing object below the accommodation space 22.

[0018] The wall portion 21 of the housing 20 is provided with a rebound plate 25. The rebound plate 25 is provided facing the hammer unit 10 in the accommodation space 22. In the present embodiment, the rebound plate 25 is provided so as to cover the hammer unit 10 from the inlet 23 to the outlet 24.

[0019] The raw material introduced from the inlet 23 is crushed by colliding with the hammer unit 10 rotating around the axis of the rotary shaft 11 and the rebound plate 25. The crushed raw material is discharged from the outlet 24.

[0020] FIG. 2 shows an outline of the hammer unit 10. As shown in FIG. 2, a plurality of plates 12 are arranged in the axial direction AX of the rotary shaft 11. The plates 12 are not particularly limited, but for example, 30 plates are provided for one crusher 100.

[0021] The hammer arm pin 13 is formed in a cylindrical shape extending in a direction along the axial direction AX of the rotary shaft 11. One hammer arm pin 13 is provided for each one hammer arm 14 arranged in the axial direction AX. The hammer arm pins 13 are arranged in plurality in contact with each other in the axial direction AX of the rotary shaft 11. In the present embodiment, 9 to 10 hammer arm pins 13 are arranged in contact with each other in the axial direction AX. By arranging the hammer arm pins 13 in this way, it is possible to prevent the crushed material from entering between the plates 12 adjacent to each other in the axial direction AX. As a result, the hammer arm pin 13 can be smoothly removed from the plate 12.

[0022] When the hammer arm pins 13 are arranged in this way, it is preferable to fix the hammer arm pin 13 arranged on one end side in the axial direction AX and the hammer arm pin 13 arranged on the other end side to the plate 12. In other words, it is preferable to fix the hammer arm pins 13 arranged on both sides in the axial direction AX to the plate 12.

[0023] In this way, by arranging the hammer arm pins 13, it is only necessary to fix the hammer arm pins 13 on both sides arranged in the axial direction of the axis AX to the plate 12, and it is possible to prevent the hammer arm pins 13 from falling out during the operation of the crusher 100.

[0024] The hammer arms 14 are provided between the plates 12 adjacent to each other. More specifically, the hammer arms 14 are fixed to the adjacent plates 12 by the hammer arm pins 13. Therefore, when the hammer arm pins 13 are removed from the plates 12, the hammer arms 14 can be removed.

[0025] Figure 3 shows an outline of the hammer arm replacement jig 200. As shown in Figure 3, the hammer arm replacement jig 200 has an attachment portion 30 formed to be attachable to the hammer arm pin 13 of the crusher 100, and an impact application portion 40 formed in a rod shape following the attachment portion 30.

[0026] The attachment portion 30 is provided at the tip of the impact application portion 40. The attachment portion 30 is formed in a cylindrical shape. The attachment portion 30 is formed, for example, with a diameter equivalent to that of the hammer arm pin 13.

[0027] The attachment portion 30 is preferably formed to be detachable from the impact application portion 40. The attachment portion 30 is formed, for example, to be screw-engageable with the impact application portion 40. By configuring the attachment portion 30 in this way, the attachment portion 30 and the impact application portion 40 can be carried in a separated state, and it is possible to enhance versatility.

[0028] Further, the attachment portion 30 is preferably formed to have a length corresponding to the length from the hammer arm pin 13 to be attached to one end in the axial direction of the axis AX of the rotating shaft 11. The hammer arm pin 13 may be provided at a deep location, that is, at a position away from one end side in the axial direction of the axis AX of the rotating shaft 11. By forming the attachment portion 30 in this way, it becomes possible to easily bring the attachment portion 30 into contact with the hammer arm pin 13 provided at a deep location.

[0029] The impact imparting portion 40 is formed in a rod shape following the attachment portion 30. The impact imparting portion 40 includes a hammer portion 41 slidably provided in a direction along the axial direction of the rotating shaft of the crusher, and a stopper 42 that regulates the sliding position of the hammer portion 41.

[0030] The hammer portion 41 is not particularly limited, but is formed in a cylindrical shape, for example. The hammer portion 41 has a through hole formed to penetrate from one end side to the other end side so as to be insertable into the impact imparting portion 40.

[0031] The hammer portion 41 is provided with a gripping portion 43 formed so that a user can grip it. In the present embodiment, the gripping portion 43 has a connecting member 44 such as a rope or a chain, and a fixing portion 45 for fixing the connecting member 44 to the hammer portion 41. The gripping portion 43 is provided on the side surface of the hammer portion 41. Note that the number of connecting members 44 fixed to the fixing portion 45 may be one or more, and a plurality of connecting members 44 may be fixed to the fixing portion 45.

[0032] The gripping portion 43 may be provided at one location of the hammer portion 41, but is preferably provided at a plurality of locations. By providing the gripping portion 43 at a plurality of locations, a plurality of users can grip the gripping portion 43, and the hammer portion 41 can be slid more smoothly.

[0033] In particular, the gripping portions 43 are preferably formed at positions spaced apart from each other in the circumferential direction of the hammer portion 41. By forming the gripping portions 43 in this way, forces can be applied to the hammer portion 41 from different directions. Therefore, the hammer portion 41 can be slid smoothly.

[0034] Note that the gripping portions 43 only need to be formed so that they can be gripped by the user. For example, the gripping portions 43 may be constituted by rod-shaped members extending in a direction perpendicular to the axis from the side surface of the hammer portion 41.

[0035] Also, the hammer portion 41 is preferably one having a weight corresponding to the required impact force. Specifically, the hammer portion 41 is preferably formed to be detachable from the impact-imparting portion 40, and a hammer portion 41 having a weight corresponding to the object to be crushed is attached and used.

[0036] The weight of the hammer portion 41 is preferably set according to the object to be crushed by the crusher 100. For example, when the object to be crushed by the crusher 100 is coal, it is preferably set to, for example, 30 to 40 kg.

[0037] The stopper 42 is provided at at least one of the axial directions in the impact-imparting portion 40. In the present embodiment, the stopper 42 is provided on the tip side close to the mounting portion 30 and the base end side far from the mounting portion 30 in the axial direction AX2 of the impact-imparting portion 40. By providing the stopper 42 on the base end side, the hammer portion 41 can be made to collide in the direction of pulling out the hammer arm pin 13.

[0038] The stopper 42 is a member formed such that the length in the direction perpendicular to the axial direction of the hammer portion 41 is longer than the diameter of the through-hole of the hammer portion 41. In the present embodiment, the stopper 42 is formed in a disc shape. In other words, the stopper 42 is formed so as to be able to contact the peripheral edge of the through-hole of the hammer portion 41 in the axial direction of the impact-imparting portion 40.

[0039] Figure 4 shows the attachment mode of the attachment part 30 to the hammer arm pin 13. The attachment part 30 is preferably formed to be detachable with respect to the hammer arm pin 13. As shown in Figure 4, the attachment part 30 is formed, for example, to be screwingly engageable with respect to the hammer arm pin 13.

[0040] Specifically, a screw hole 13a is formed on one end side of the hammer arm pin 13. A screw 31 is formed on the tip side of the attachment part 30. The screw 31 of the attachment part 30 is formed to be screwingly engageable with the screw hole 13a of the hammer arm pin 13. Thereby, the attachment part 30 can be attached to the hammer arm pin 13.

[0041] Furthermore, by screwing the attachment part 30 to the hammer arm pin 13, it is possible to suppress so-called floating, in which the connection between the attachment part 30 and the hammer arm pin 13 is displaced when an impact is applied by the hammer part 41. Furthermore, by adopting a configuration in which both are screwed together, it is possible to easily position the attachment part 30 only by inserting the hammer arm pin 13 through the through hole of the plate 12.

[0042] Figure 5 shows the flow of the method for replacing the hammer arm 14. As shown in Figure 5, when replacing the hammer arm 14, an operation is performed by opening a through hole (not shown) for replacing the hammer arm on the side surface of the housing 20 of the crusher 100.

[0043] An impact application step (step S01) of applying an impact to the hammer arm pin 13 from a direction along the arrangement direction of the plate 12 is performed. In the impact application step of step S01, for example, the attachment part 30 of the hammer arm replacement jig 200 is inserted into the through hole and screwed to the top of the hammer arm pin 13. Next, the hammer part 41 is slid forcefully toward the stopper 42 to apply an impact to the hammer arm pin 13.

[0044] Further, when a plurality of hammer arm pins 13 are arranged in contact with each other in the axial direction AX of the rotary shaft 11, an impact may be applied to the hammer arm pin 13 arranged at the end in the axial direction AX of the rotary shaft 11. By applying an impact in this way, the impact can be propagated to the entire plurality of hammer arm pins 13 by a single impact. As a result, the impact application process can be executed with a smaller number of impact applications than when an impact is individually applied to the plurality of hammer arm pins 13.

[0045] Thereafter, a removing step is performed in which the hammer arm pin 13 is moved in the axial direction AX of the rotary shaft 11 to remove the hammer arm 14 engaged with the hammer arm pin 13 (step S02).

[0046] In the removing step of step S02, for example, the hammer arm replacement jig 200 may be pushed in the axial direction AX of the rotary shaft 11 in a direction approaching the crusher 100 to move the hammer arm pin 13 connected to the attachment portion 30. In such a case, the hammer arm pin 13 located at the tip in the direction in which the hammer arm replacement jig 200 is pushed is pushed out and the engagement with the plate 12 is released.

[0047] Furthermore, when the hammer arm replacement jig 200 is pushed in, the stopper 42 contacts the through hole and the movement of the hammer arm replacement jig 200 stops. In such a case, it is preferable to replace the attachment portion 30 with a longer one. By pushing in the hammer arm replacement jig 200 with the replaced attachment portion 30, the hammer arm pin 13 can be moved further inwards. In this way, by pushing in the hammer arm replacement jig 200 while replacing the attachment portion 30, it is preferable to release the engagement between all the hammer arm pins 13 and the plate 12.

[0048] In the removal step of step S02, for example, the hammer arm replacement jig 200 may be pulled in the direction away from the crusher 100 in the axial direction AX of the rotating shaft 11 so as to move the hammer arm pin 13 connected to the mounting portion 30. In this case, similar to the case of pushing in the hammer arm replacement jig 200, the mounting portion 30 may be replaced with a longer one according to the position of the hammer arm pin 13 in the axial direction AX.

[0049] After that, an arrangement step (step S03) of arranging a new hammer arm at the position of the removed hammer arm is performed. Finally, a fixing step (step S04) of fixing the new hammer arm 14 to the plate 12 using the hammer arm pin 13 is performed.

[0050] FIG. 6 shows a mode in which the hammer arm replacement jig 200 is installed in the impact application step of step S01 in FIG. 5. As shown in FIG. 6, the hammer arm replacement jig 200 may be suspended and used, for example, by a frame 50 composed of a plurality of columns 51 and a beam 52 spanned across the plurality of columns 51.

[0051] In the present embodiment, the frame 50 is provided such that a rectangular parallelepiped contour is formed by the columns 51 and the beam 52. In other words, the beam 52 is spanned in the circumferential direction above the columns 51. Further, one beam 52a is provided so as to be spanned at the center of the beams 52 that are spanned in the circumferential direction and face each other.

[0052] The hammer arm replacement jig 200 is suspended from the beam 52a. More specifically, the tip side and the base end side of the hammer arm replacement jig 200 are connected to the beam 52a by members such as wires and chains. Note that the frame 50 is not limited to such a mode, and it is sufficient if the hammer arm replacement jig 200 can be held. For example, it may be installed on a gantry (not shown). Further, a reinforcing member may be used for the frame 50 as needed.

[0053] FIG. 7 shows a mode in which the attachment portion 30 of the hammer arm replacement jig 200 is attached to the hammer arm pin 13 in the impact application step of step S01 in FIG. 5.

[0054] As shown in FIG. 7, the impact application portion 40 of the hammer arm replacement jig 200 is positioned in the direction D1 along the axis AX of the rotating shaft 11 of the crusher 100. Note that, in the present embodiment, the direction D1 along the axis AX of the rotating shaft 11 is also the direction along the arrangement direction of the plates 12.

[0055] Next, the attachment portion 30 of the hammer arm replacement jig 200 is inserted and screwed onto the hammer arm pin 13. By doing so, it becomes possible to directly apply an impact in the direction of the axis AX to the hammer arm pin 13.

[0056] FIG. 8 shows a mode in which the hammer portion 41 of the hammer arm replacement jig 200 is slid in the impact application step of step S01 in FIG. 5. As shown in FIG. 8, the user grips the gripping portion 43 and pulls or pushes to slide the hammer portion 41 forcefully toward the stopper 42. That is, it is slid in the direction D1 along the axial direction of the rotating shaft of the crusher to apply an impact to the hammer arm pin.

[0057] In the impact application step of step S01, an impact is applied in at least one of the forward and backward directions in the axial direction of the rotating shaft. Note that the number of times an impact is applied in the impact application step of step S01 is not particularly limited and may be appropriately changed according to the embodiment. For example, the impact application step of step S01 may be performed until the fixation of the hammer arm pin 13 is released.

[0058] Furthermore, in the impact application step of step S01, it is preferable that an impact is applied to the rear in the axial direction of the rotating shaft. In such a case, for example, in the direction D1 along the axial direction of the rotating shaft of the crusher, an impact is applied in the direction away from the crusher. By applying the impact in such a manner, the impact is applied in the same direction as the direction in which the hammer arm pin is pulled out, so that it becomes possible to easily perform the subsequent pulling out of the hammer arm pin. In addition, the impact applied to the crusher can be minimized, and the risk of the crusher malfunctioning or the like can be reduced.

[0059] As described above, conventionally, since a jack or a cylinder was used, it was impossible to apply an impact and it was difficult to remove the hammer arm pin. According to the method for replacing the hammer arm of the present invention, etc., there are an impact application step of applying an impact to the hammer arm pin 13 from the direction D1 along the arrangement direction of the plate 12, and a removal step of removing the hammer arm 14 after the impact is applied to the hammer arm pin 13. Thereby, it becomes possible to remove crushed materials or the like located in the gap provided between the hammer arm pin 13 and the members around it.

[0060] Therefore, the operation of removing the hammer arm pin 13 from the plate 12 can be performed smoothly, and the hammer arm pin 13 can be easily removed. As a result, it becomes possible to quickly replace the hammer arm 14. That is, by using the hammer arm replacement jig 200 to replace the hammer arm 14, the hammer arm 14 can be easily removed.

[0061] In addition, the hammer arm replacement jig 200 is provided with a gripping portion 43 that can be gripped by the user on the hammer portion 41. The user can suppress the occurrence of events to be avoided, such as pinching the hand with the hammer portion 41, by gripping the gripping portion 43 and sliding the hammer portion 41.

[0062] The hammer arm replacement jig 200 of the present invention applies an impact to the hammer arm pin 13 by the hammer portion 41. Therefore, even when the crusher 100 is installed in a narrow space, an impact can be applied to the hammer arm pin 13 without using machinery. For this reason, power such as that from a motor is not required, and it can be used even in places without a power supply.

[0063] Also, since the user slides the hammer portion 41, the operation of applying the impact can be finely adjusted. In this way, by sliding the hammer portion 41 and applying an impact to the hammer arm pin 13, the impact can be applied in multiple stages compared to the case of applying an impact by freely dropping a weight or the like vertically. Further, by sliding the hammer portion 41, it becomes possible to apply an impact not only in the direction of pushing in the hammer arm pin 13 but also in the direction of pulling it out.

[0064] In the above-described embodiment, an example in which a plurality of hammer arm pins 13 are arranged in contact with each other in the axial direction AX of the rotating shaft 11 has been described. The hammer arm pins 13 may be provided with a space in the axial direction AX of the rotating shaft 11.

[0065] FIG. 9 shows another mounting mode of the hammer arm pin 13. As shown in FIG. 9, the hammer arm pins 13 are provided with a space in the axial direction AX of the rotating shaft 11. Even when the hammer arm pins 13 are provided in this way, as in the above-described embodiment, by applying an impact to the hammer arm pins 13 from the direction along the arrangement direction of the plates 12, the hammer arm 14 can be easily removed.

[0066] In the above-described embodiment, an example in which the hammer portion 41 is formed in a cylindrical shape has been described. However, the hammer portion 41 is not limited to such a form and can be formed in various shapes such as a prismatic shape. For example, by forming the hammer portion 41 in an oblong spherical shape or a frustum of a cone shape, it becomes possible to more intensively apply the impact generated when the hammer portion 41 is slid to the stopper 42. As a result, even with a light weight, it becomes possible to easily remove the crushed material.

[0067] Further, the hammer portion 41 is preferably formed so that its weight can be adjusted. For example, the hammer portion 41 may be formed in a hollow shape and configured to be able to accommodate a liquid such as water. That is, by adjusting the amount of the contents accommodated in the hammer portion 41, the weight of the hammer portion 41 can be adjusted. As a result, for example, when it is desired to increase the impact by the hammer portion 41, it becomes possible to easily increase the impact by increasing the amount of the contents accommodated in the hammer portion 41.

[0068] Also, by forming the hammer portion 41 in this way, it becomes possible to adjust the impact applied to the hammer arm pin 13 according to the object to be crushed. As a result, it becomes possible to suppress applying an excessive impact to the hammer arm pin 13, and it becomes possible to extend the service life of the crusher 100.

Explanation of Reference Numerals

[0069] 100 Crusher 10 Hammer unit 11 Rotating shaft 12 Plate 13 Hammer arm pin 14 Hammer arm 200 Hammer arm replacement jig 30 Mounting portion 40 Impact imparting portion 41 Hammer portion 42 Stopper 43 Gripping portion

Claims

1. A method for replacing a hammer arm of a crusher, the crusher having a rotating shaft, a plurality of disk-shaped plates arranged in the axial direction of the rotating shaft, and a plurality of hammer arms fixed to the plates via hammer arm pins, comprising: an impact applying step of applying an impact to the hammer arm pin from a direction along the arrangement direction of the plates; a removing step of moving the hammer arm pin in the axial direction of the rotating shaft after the impact applying step to remove the hammer arm engaged with the hammer arm pin; an arranging step of arranging a new hammer arm at the position of the removed hammer arm; a fixing step of fixing the new hammer arm to the plate using the hammer arm pin; The method for replacing a hammer arm, including the above steps.

2. The method for replacing a hammer arm according to claim 1, wherein in the removing step, the hammer arm pin arranged at the axial end of the rotating shaft among the plurality of hammer arm pins arranged in contact with each other in the axial direction of the rotating shaft is moved.

3. The method for replacing a hammer arm according to claim 1, wherein in the impact applying step, an impact is applied to at least one of the front and rear directions in the axial direction of the rotating shaft.

4. The method for replacing a hammer arm according to claim 2, wherein in the impact applying step, an impact is applied to at least one of the front and rear directions in the axial direction of the rotating shaft.

5. The method for replacing a hammer arm according to claim 3 or 4, wherein in the impact applying step, an impact is applied to the rear in the axial direction of the rotating shaft.

6. The method for replacing a hammer arm according to claim 3 or 4, wherein in the impact applying step, an impact is applied to the hammer arm pin arranged at the axial end of the rotating shaft among the plurality of hammer arm pins arranged in contact with each other in the axial direction of the rotating shaft.

7. A hammer arm replacement jig used for replacing a hammer arm of a crusher, the crusher having a rotating shaft, a plurality of disk-shaped plates arranged in the axial direction of the rotating shaft, and a plurality of hammer arms fixed to the plates via hammer arm pins, comprising: a mounting portion formed to be attachable to the hammer arm pin of the crusher; Following the mounting portion, there is a shock-imparting portion formed in a rod shape and applying an axial shock to the mounting portion. The shock-imparting portion includes a hammer portion slidably provided in a direction along the axial direction of the rotation axis, and a stopper for regulating the slide position of the hammer portion, and is a hammer arm replacement jig. **Claim 8** The mounting portion is detachably formed with respect to the shock-imparting portion and is formed according to the length from the hammer arm pin to be attached to one end in the axial direction of the rotation axis. The hammer arm replacement jig according to claim 7. **Claim 9** The stopper of the shock-imparting portion is provided on the proximal end side away from the mounting portion in the axial direction. The hammer arm replacement jig according to claim 7 or 8.

Images