Impact rotary tool

Abstract

To reduce vibrations in a radial direction that are caused when tightening an object to be tightened.SOLUTION: An impact rotary tool 10 comprises an anvil 1 that transmits impact rotating force from a hammer 30 to a tip tool 20. The anvil 1 is constituted of a first member 11 and a second member 12. The first member 11 holds the tip tool 20. The second member 12 is fitted with the first member 11 and is applied with the impact rotating force. A fitted part 100 which is a part at which the first member 11 and the second member 12 are fitted to each other has permitting mechanisms (111A and 121A). The permitting mechanisms (111A and 121A) permit a first rotating shaft AX1 to directionally deviate with respect to a second rotating shaft AX2. The first rotating shaft AX1 is a rotating shaft of the first member 11 and the second rotating shaft AX2 is a rotating shaft of the second member 12.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a rotary impact tool, and more particularly to an impact rotary tool having a function of reducing vibrations that occur when tightening an object to be tightened, such as a screw or a bolt. [Background technology]

[0002] Patent Document 1 describes a rotary impact tool equipped with an anvil that transmits the rotary impact force from a hammer capable of rotary and reciprocating motion to a tool tip, in which the anvil is divided into a tool tip mounting member to which the tool tip is attached and a rotary impact member that transmits the rotary impact force from the hammer to the tool tip mounting member, with a cushioning material provided between these two members. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 7-237152 Summary of the Invention [Problem to be solved by the invention]

[0004] In the technique described in Patent Document 1, a buffer material is provided between the tool attachment member and the rotary striking member to reduce axial vibrations that occur when tightening an object to be tightened, such as a screw.

[0005] However, in the device disclosed in Patent Document 1, the tool attachment member and the rotary striking member are fixedly connected (in other words, so as not to allow the direction of the former rotary shaft to deviate from that of the latter) with the rotation axis of the former coinciding with the rotation axis of the latter. Therefore, when the direction of the latter rotary shaft deviates from the insertion direction of the object to be fastened, such as a screw, the direction of the former rotary shaft also deviates from the insertion direction, causing radial vibration.

[0006] An object of the present disclosure is to provide a rotary impact tool that can reduce radial vibrations that occur when tightening an object to be tightened, such as a screw. [Means for solving the problem]

[0007] A rotary impact tool according to one embodiment of the present disclosure includes an anvil that transmits an impact rotational force from a hammer to a tool bit. The anvil is composed of a first member and a second member. The first member holds the tool bit. The second member is engaged with the first member, and the impact rotational force is applied to the second member. An engagement portion where the first member and the second member are engaged with each other has an allowance mechanism. The allowance mechanism allows directional deviation of the first rotation axis relative to the second rotation axis. The first rotation axis is the rotation axis of the first member, and the second rotation axis is the rotation axis of the second member. The interlocking portion includes a first interlocking portion and a second interlocking portion. The first interlocking portion is a part of the first member and is interlocked with the second member. The second interlocking portion is a part of the second member and is interlocked with the first member. A first surface which is one surface of the first interlocking portion and a second surface which is one surface of the second interlocking portion face each other. The allowing mechanism is realized by forming at least a portion of at least one of the first surface and the second surface into a convex curved surface. The impact rotary tool according to one embodiment of the present disclosure includes an anvil that transmits an impact rotational force from a hammer to a tool bit. The anvil is composed of a first member and a second member. The first member holds the tool bit. The second member is engaged with the first member, and the impact rotational force is applied to the second member. An engagement portion where the first member and the second member are engaged with each other has a tolerance mechanism. The tolerance mechanism allows a directional deviation of the first rotation axis with respect to the second rotation axis. The first rotation axis is the rotation axis of the first member, and the second rotation axis is the rotation axis of the second member. The engagement portion where the first member and the second member are engaged with each other has a tolerance mechanism. The tolerance mechanism allows a directional deviation of the first rotation axis, which is the rotation axis of the first member, with respect to the second rotation axis, which is the rotation axis of the second member. The engagement portion further has a limiting mechanism that limits the directional deviation. The mating portion is formed in a cylindrical shape, and the limiting mechanism includes a shaft-shaped centering member disposed inside the mating portion. Effect of the Invention

[0008] The rotary impact tool of the present disclosure has an advantage in that it is possible to reduce radial vibrations that occur when tightening an object to be tightened, such as a screw. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is an exploded perspective view of an anvil that constitutes a rotary impact tool according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a side view of the anvil. [Diagram 3] FIG. 3A is a cross-sectional view of the anvil of the above embodiment when no misalignment occurs, and FIG. 3B is a cross-sectional view of the anvil of the above embodiment when a misalignment occurs. [Figure 4]Figure 4A is a cross-sectional view of the engaging portion of the anvil when a spherical convex curved portion is present on a portion of the second surface, Figure 4B is a cross-sectional view of the anvil when a spherical convex curved portion is present on a portion of the first surface, and Figure 4C is a cross-sectional view of the anvil when a spherical convex curved portion is present on a portion of each of the first surface and the second surface. [Diagram 5] Figure 5A is a cross-sectional view of the anvil when a spherical convex curved portion is present on almost the entire second surface of the mating portion, Figure 5B is a cross-sectional view of the anvil when a spherical convex curved portion is present on almost the entire first surface, and Figure 5C is a cross-sectional view of the anvil when a spherical convex curved portion is present on almost the entire first surface and second surface. [Figure 6] FIG. 6A is a cross-sectional view of the engaging portion of the anvil when an R-shaped convex curved surface portion is present on the second surface, FIG. 6B is a cross-sectional view of the engaging portion when an R-shaped convex curved surface portion is present on the first surface, and FIG. 6C is a cross-sectional view of the engaging portion when an R-shaped convex curved surface portion is present on each of the first surface and the second surface. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The figures described in the following embodiments are schematic diagrams, and the ratios of the sizes and thicknesses of the components do not necessarily reflect the actual dimensional ratios. Note that the configurations described in the following embodiments are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

[0011] (1) Impact rotary tool The rotary impact tool 10 includes an anvil 1 as shown in FIGS. 1 to 3A.

[0012] The anvil 1 transmits the impact torque from the hammer 30 to the tool tip 20. The impact torque includes an axial striking force and a torque around the axis. In this embodiment, the axial direction refers to the direction of a rotation axis AX2, which will be described later, and the torque around the axis refers to the circumference of the rotation axis AX2. The tool tip 20 tightens an object to be tightened, such as a screw or a bolt, by using the impact torque.

[0013] (2) Anvil The anvil 1 is composed of a first member 11 and a second member 12. The first member 11 holds a tool bit 20. The first member 11 is engaged with the second member 12, and the above-mentioned impact rotational force is applied thereto.

[0014] Specifically, the rear end of the first member 11 and the front end of the second member 12 are engaged with each other, and the tool tip 20 is attached to the front end side of the first member 11. The front end side of the first member 11 is movable relative to the second member 12 in the radial direction (the direction intersecting the axial direction).

[0015] When an impact rotational force is applied from the hammer 30 to the rear end side of the second member 12 while the tool bit 20 is engaged with an object to be fastened such as a screw, the impact rotational force is transmitted to the tool bit 20 via the second member 12 and the first member 11. As a result, the impact rotational force acts on the object to be fastened such as a screw, and the object to be fastened such as a screw is pushed in the insertion direction of the screw hole or the like and fastened.

[0016] (3) Fitting section The mating portion 100 is a portion where the first member 11 and the second member 12 are mated with each other.

[0017] The mating portion 100 includes a first mating portion 111 and a second mating portion 121. The first mating portion 111 is a part of the first member 11 and is a part mated with the second member 12. The second mating portion 121 is a part of the second member 12 and is a part mated with the first member 11. A first surface 111A which is one surface of the first mating portion 111 and a second surface 121A which is one surface of the second mating portion 121 face each other.

[0018] Specifically, each of the first mating portion 111 and the second mating portion 121 has a cylindrical shape in which notched portions (notched portions) and non-notched portions (non-notched portions) are alternately formed. The non-notched portions of the first mating portion 111 and the notched portions of the second mating portion 121 mesh with each other to form the mating portion 100.

[0019] (4) Permitting mechanism The mating portion 100 in this embodiment has an allowance mechanism (111A, 121A).

[0020] The tolerating mechanisms (111A, 121A) are mechanisms that tolerate directional misalignment of the first rotation axis AX1 with respect to the second rotation axis AX2. The first rotation axis AX1 is the rotation axis of the first member 11, and the second rotation axis AX2 is the rotation axis of the second member 12.

[0021] The occurrence of a directional deviation occurs when, for example, as shown in FIG. 3B, when the angle θ between the first rotation axis AX1 and the second rotation axis AX2 is set to be greater than a predetermined first threshold value θ1.

[0022] The first threshold value θ1 is, for example, 0 degrees, but may be a value greater than 0 degrees (for example, a value within the range of 0.5 degrees to 2 degrees).

[0023] In this way, the tolerant mechanism (111A, 121A) allows the directional deviation between the first rotating shaft AX1 and the second rotating shaft AX2, so that even if the second rotating shaft AX2 deviates from the insertion direction of the object to be fastened, the first rotating shaft AX1 can be maintained in agreement with the insertion direction of the object to be fastened. As a result, it is possible to reduce radial vibrations that occur when the object to be fastened is fastened.

[0024] (4-1) Means of realizing the tolerance mechanism The allowing mechanism (111A, 121A) in this embodiment is realized by forming at least a part of at least one of the first surface 111A and the second surface 121A facing each other into a convex curved surface.

[0025] (4-1-1) Arrangement of convex curved surfaces The portion formed in a convex curved shape (hereinafter, referred to as a "convex curved portion") is present, for example, on either the first surface 111A or the second surface 121A.

[0026] That is, the convex curved surface portion is, for example, as shown in FIG. 4A, FIG. 5A, and FIG. 6A. 2 Side 1 2 Alternatively, the convex curved surface portion may be present in the first portion 1A, as shown in, for example, FIG. 4B, FIG. 5B, and FIG. 6B. 1 Side 1 1 It may be present in 1A.

[0027] In this case, the other surface (the surface without the convex curved surface portion) is usually a flat surface as shown in Figures 4A, 5A, and 6A, or as shown in Figures 4B, 5B, and 6B. However, the other surface may be formed as a concave curved surface whose curvature is smaller than that of the convex curved surface portion.

[0028] This allows the permitting mechanism (111A, 121A) to be easily realized.

[0029] (4-1-1a) Preferred layout 1 The convex curved surface portion is preferably present in a part of either the first surface 111A or the second surface 121A.

[0030] The convex curved surface portion in this embodiment is, for example, as shown in FIG. 2 Side 1 2 1A or, as shown in FIG. 4B, 1 Side 1 1 It exists as part of 1A.

[0031] In this case, the other portion of the one surface (the surface on which the convex curved surface portion exists) and the other surface (the surface on which the convex curved surface portion does not exist) are usually flat surfaces as shown in Figures 4A and 4B. However, the other portion of the one surface and the other surface may be formed as a concave surface whose curvature is smaller than that of the convex curved surface portion.

[0032] This makes it possible to reduce the contact area between the first surface 111A and the second surface 121A. As a result, it is possible to easily realize an allowance mechanism (111A, 121A) that has a wide allowance range for directional misalignment.

[0033] (4-1-1b) Preferred layout 2 However, the convex curved surface portion may be present on substantially the entirety of either the first surface 111A or the second surface 121A, as shown in, for example, FIGS. 5A and 5B.

[0034] This makes it possible to increase the contact area between the first surface 111A and the second surface 121A, and as a result, it is possible to easily realize a highly durable allowable mechanism (111A, 121A).

[0035] (4-1-1c) Other layouts Alternatively, the convex curved surface portion may be present on both the first surface 111A and the second surface 121A, for example, as shown in Figures 4C and 5C. In this case, each surface may have a part that is a convex curved surface portion as shown in Figure 4C, or may have substantially the entirety that is a convex curved surface portion as shown in Figure 5C.

[0036] (4-1-2) Shape of the convex curved surface The convex curved surface portion is, for example, a convex curved surface with a constant curvature (i.e., a spherical surface), although the curvature does not have to be constant.

[0037] (4-1-2a) Preferred Shape The shape of the convex curved surface portion is, for example, the first curved surface portion shown in FIG. 2 Side 1 2 1A, the first one shown in FIG. 4B 1 Side 1 1 1A, the first surface 111A and the second surface 121A shown in FIG. 4C, and the second surface 121A shown in FIG. 2 Side 1 2 1A, the first one shown in FIG. 5B 1 Side 1 1 1A, the first surface 111A and the second surface 121A shown in FIG. 5C are spherical.

[0038] This makes it possible to more simply realize the permitting mechanisms (111A, 121A).

[0039] (4-1-2b) Other shapes Alternatively, the shape of the convex curved surface may be a curved surface (a so-called R curved surface) in which the curvature is large on the end side and becomes smaller as the distance from the end increases, such as second surface 121A shown in FIG. 6A, first surface 111A shown in FIG. 6B, or second surface 121A and first surface 111A shown in FIG. 6C.

[0040] However, the shape of the convex curved surface is not limited to a spherical surface or a rounded surface, and may be any smooth convex curved surface.

[0041] (5) Restriction mechanism It is preferable that the mating portion 100 further includes a limiting mechanism (14, 15). The limiting mechanism (14, 15) is a mechanism for limiting directional deviation.

[0042] The direction shift is restricted, for example, by making the angle θ smaller than a predetermined second threshold θ2 (where θ1<θ2). The second threshold θ2 is, for example, 5 degrees, but is not limited to this. The second threshold θ2 may be, for example, a value within a range of 4 degrees to 6 degrees, or a value within a range of 3 degrees to 7 degrees.

[0043] The limiting mechanisms (14, 15) limit the directional deviation, thereby ensuring the durability of the anvil 1.

[0044] (5-1) Centering parts The limiting mechanism (14, 15) includes a shaft-shaped centering member 14. The centering member 14 is disposed inside the mating portion 100.

[0045] This allows the limiting mechanisms (14, 15) to be realized simply.

[0046] (5-2) Elastic member The limiting mechanism (14, 15) further includes a ring-shaped elastic member 15. The elastic member 15 is provided so as to surround the outer periphery of the engaging portion 100.

[0047] For example, a groove may be formed in the circumferential direction on the outer periphery of the mating portion 100, and the elastic member 15 may be fitted into this groove.

[0048] The elastic member 15 limits the directional deviation, so that a limiting mechanism (14, 15) having high durability can be easily realized.

[0049] (6) Cushioning materials The anvil 1 further includes a buffer member 13. The buffer member 13 is disposed inside the mating portion 100. The buffer member 13 suppresses axial vibrations that occur when an object to be fastened is fastened.

[0050] (7) Axial clearance The centering member 14 and the buffer member 13 create an axial gap between the first member 11 and the second member 12. The axial gap allows the buffer member 13 to expand and contract, and also contributes to allowing and limiting angular misalignment.

[0051] As described above, in the impact rotary tool 10 of this embodiment, the tolerance mechanisms (111A, 121A) allow directional misalignment, and the limiting mechanisms (14, 15) limit directional misalignment, thereby ensuring the durability of the anvil 1 and reducing radial vibration. In addition, the buffer member 13 reduces axial vibration.

[0052] (8) Summary The impact rotary tool (10) according to the first aspect includes an anvil (1) that transmits an impact rotational force from a hammer (30) to a tool bit (20), and is characterized as follows. That is, the anvil (1) is composed of a first member (11) and a second member (12). The first member (11) holds the tool bit (20). The first member (11) is engaged with the second member (12), and the impact rotational force is applied to the second member (12). An engagement portion (100) where the first member (11) and the second member (12) are engaged with each other has an allowance mechanism (111A, 121A). The allowance mechanism (111A, 121A) is a mechanism that allows a directional deviation of the first rotation axis (AX1) with respect to the second rotation axis (AX2). The first rotation axis (AX1) is the rotation axis of the first member (11). The second rotation axis (AX2) is the rotation axis of the second member (12).

[0053] According to this aspect, by allowing directional misalignment between the first and second rotating shafts corresponding to the first and second members that constitute the anvil, even if the second rotating shaft deviates from the insertion direction of the object to be fastened, it is possible to maintain the first rotating shaft in alignment with the insertion direction of the object to be fastened, thereby reducing radial vibration.

[0054] In contrast, as explained in the Background Art, in a case where a first member is fixedly engaged with a second member, directional deviation of the first rotating shaft, which is the rotating shaft of the first member, relative to the second rotating shaft, which is the rotating shaft of the second member, is not permitted, and radial vibration occurs.

[0055] In the impact rotary tool (10) according to the second aspect, in the first aspect, the mating portion (100) includes a first mating portion (111) and a second mating portion (121). The first mating portion (111) is a part of the first member (11) and is a part mated with the second member (12). The second mating portion (121) is a part of the second member (12) and is a part mated with the first member (11). A first surface (111A) which is one surface of the first mating portion (111) and a second surface (121A) which is one surface of the second mating portion (121) face each other. The allowing mechanism (111A, 121A) is realized by forming at least a part of at least one of the first surface (111A) and the second surface (121A) into a convex curved shape.

[0056] According to this aspect, the permitting mechanism can be easily realized.

[0057] In the impact rotating tool (10) according to the third aspect, in the second aspect, the allowing mechanism (111A, 121A) is realized by forming a portion of either the first surface (111A) or the second surface (121A) into a convex curved shape.

[0058] According to this aspect, by reducing the contact area between the first surface and the second surface, it is possible to easily realize an allowance mechanism that allows a wide range of directional misalignment.

[0059] In the impact rotating tool (10) according to the fourth aspect, in the second aspect, the allowing mechanism (111A, 121A) is realized by forming substantially the entirety of either the first surface (111A) or the second surface (121A) into a convex curved shape.

[0060] According to this aspect, by increasing the contact area between the first surface and the second surface, a highly durable allowing mechanism can be easily realized.

[0061] The rotary impact tool (10) according to a fifth aspect is the third or fourth aspect, wherein the portions of the first surface (111A) and the second surface (121A) formed into a convex curved shape have a constant curvature.

[0062] According to this aspect, the permitting mechanism can be realized more simply.

[0063] In the rotary impact tool (10) according to a sixth aspect, in any one of the first to fifth aspects, the engaging portion (100) further includes a limiting mechanism (14, 15). The limiting mechanism (14, 15) is a mechanism that limits the directional deviation.

[0064] According to this aspect, by limiting the directional deviation, it is possible to ensure the durability of the anvil.

[0065] In the seventh aspect of the rotating impact tool (10), in the sixth aspect, the mating portion (100) is formed in a cylindrical shape. The limiting mechanism (14, 15) includes a shaft-shaped centering member (14). The centering member (14) is disposed inside the mating portion (100).

[0066] According to this aspect, the limiting mechanism can be easily realized.

[0067] In the rotary impact tool (10) according to an eighth aspect, in the seventh aspect, the limiting mechanism (14, 15) further includes a ring-shaped elastic member (15). The elastic member (15) is provided so as to surround the outer periphery of the engagement portion (100).

[0068] According to this aspect, a highly durable limiting mechanism can be easily realized.

[0069] In the rotating impact tool (10) according to a ninth aspect, in the seventh or eighth aspect, the anvil (1) further includes a buffer member (13). The buffer member (13) is disposed inside the mating portion (100). The centering member (14) and the buffer member (13) create a gap along the direction of the second rotation axis between the first member (11) and the second member (12).

[0070] According to this aspect, it is possible to reduce axial vibrations by expanding and contracting the buffer member, while also reducing radial vibrations by allowing and restricting directional misalignment. [Explanation of symbols]

[0071] 10 Impact rotary tools 20 Tip tools 30 Hammer 1 Anvil 100 Engagement part 11 First member 111 First fitting part 111A 1st page 12 Second member 121 Second fitting part 121A 2nd side 13. Cushioning materials 14 Centering member 15 Elastic member AX1 First rotation axis AX2 Second rotation axis

Claims

1. In the impact rotary tool, an anvil is provided to transmit an impact rotational force from a hammer to a tip tool, The anvil is A first member for holding the tool bit; a second member to which the first member is engaged and to which the impact rotational force is applied; a fitting portion where the first member and the second member are fitted to each other has a tolerance mechanism that allows a directional shift of a first rotation axis that is a rotation axis of the first member with respect to a second rotation axis that is a rotation axis of the second member, The mating portion is A first mating portion that is a part of the first member and is mated with the second member; a second mating portion that is a part of the second member and that is mated with the first member; A first surface which is one surface of the first mating portion and a second surface which is one surface of the second mating portion face each other, The allowing mechanism is realized by forming at least a part of at least one of the first surface and the second surface into a convex curved surface. Impact rotary tool.

2. The tolerance mechanism is realized by forming a part of either the first surface or the second surface into a convex curved surface. The rotary impact tool according to claim 1.

3. The tolerance mechanism is realized by forming substantially the entirety of either the first surface or the second surface into a convex curved surface. The rotary impact tool according to claim 1.

4. The convex curved portions of the first surface and the second surface have a constant curvature. The rotary impact tool according to claim 2 or 3.

5. The engaging portion further has a limiting mechanism for limiting the directional deviation. The rotary impact tool according to any one of claims 1 to 4.

6. The mating portion is formed in a cylindrical shape, The limiting mechanism includes a shaft-shaped centering member disposed inside the mating portion. The rotary impact tool according to claim 5.

7. A rotary impact tool having an anvil that transmits impact rotational force from a hammer to a tip tool, The anvil is A first member for holding the tool bit; a second member to which the first member is engaged and to which the impact rotational force is applied; a fitting portion where the first member and the second member are fitted to each other has a tolerance mechanism that allows a directional shift of a first rotation axis that is a rotation axis of the first member with respect to a second rotation axis that is a rotation axis of the second member, The engaging portion further includes a limiting mechanism for limiting the directional deviation, The mating portion is formed in a cylindrical shape, The limiting mechanism includes a shaft-shaped centering member disposed inside the mating portion. Impact rotary tool.

8. The limiting mechanism further includes a ring-shaped elastic member provided to surround an outer periphery of the engagement portion. The rotary impact tool according to claim 6 or 7.

9. The anvil further has a buffer member disposed inside the mating portion, The centering member and the buffer member generate a gap between the first member and the second member along the direction of the second rotation axis. The rotary impact tool according to any one of claims 6 to 8.

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