JP6314522B2 - Impact test hammer - Google Patents

Description

  The present invention relates to an impact test hammer used for impact excitation in a modal analysis experiment or the like.

  A modal analysis experiment may be performed in structural analysis of a structure. In this modal analysis experiment, an operator impacts a structure with a hammer and analyzes the vibration of the structure at that time.

  FIG. 14 is a diagram showing the configuration of the hammer 100 used in the modal analysis experiment. The hammer 100 is provided with a plurality of impact portions 101 so as to be replaceable, and can be used by replacing them according to the application. In FIG. 14, a metal head 101a, a resin head 101b, and a rubber head 101c are used, and any one of these is mounted on the hammer body 102.

  The reason for exchanging the impact portion 101 is to allow a test according to the purpose to be performed by adjusting the frequency of the impact. This frequency correlates with the duration of the impact force (impact duration).

  According to Non-Patent Document 1, it is indicated that the impact duration varies depending on the tip shape of the hammer, and the impact duration is shorter as the curvature is larger, and longer as the curvature is smaller. Further, according to Non-Patent Document 2, an impact caused by a hammer can be expressed using a spring model, and the spring constant increases as the hit point rigidity increases. Therefore, it can be seen from these Non-Patent Documents 1 and 2 that the impact duration can be adjusted by changing the rigidity of the hit point of the object to be measured and the hammer.

  Therefore, if you want to perform analysis that focuses on low-frequency vibrations, you can suppress vibration on the high-frequency side by increasing the impact duration to increase vibration measurement accuracy in the low-frequency region. When it is desired to perform analysis focusing on the vibration in the region, the vibration on the low frequency side is suppressed by shortening the impact duration, and the vibration measurement accuracy on the high frequency side is increased. In this way, the impact unit 101 is provided so as to be selectable so that vibrations in a frequency range according to the purpose can be detected.

  Patent Document 1 discloses an impact test hammer 110 as shown in FIG. The impact test hammer 110 includes a head 111 that makes a hit point with respect to the measured object 115, a shaft 112 integrated with the head 111, a plurality of hammer weights 113 inserted into the shaft 112, and an elasticity disposed between the hammer weights 113. A member 114 is provided.

  Then, after the head 111 comes into contact with the measurement object 115, the hammer weight 113 slides on the shaft 112 with inertial force, and the impact is sustained. In this case, the adjustment of the impact duration when the hammer weight 113 is the same is performed by exchanging the head 111 with a different rigidity.

  In Japanese Utility Model Laid-Open No. 3-6544, the outer peripheral portion of the wheel-shaped hitting member 120 as shown in FIG. 16 is divided into a plurality of hitting piece pieces 120A to 120D each made of a material having different hitting characteristics. An impact vibration apparatus has been proposed. Here, in the striking member 120, the striking piece 120A is made of iron, the striking piece 120B is made of plastic, the striking piece 120C is made of hard rubber, and the striking piece 120D is made of soft rubber. In the test, the striking member 120 is rotated and brought into contact with any one of the striking piece 120A to the striking piece 120D.

Japanese Utility Model Publication No. 61-149854 Japanese Utility Model Publication No. 3-6544

Kishi, Ohno, Mikami, Ando, “Effects of difference in boundary conditions in impact test of weight drop on impact behavior of reinforced concrete beam”, JSCE Proceedings No. 731 / 1-63, 299-316, 2003. 4 Hone, Sato, Iwata, Komatsuzaki, Hongo, “Analysis of spherical elastic collision system”, Japan Society of Mechanical Engineers [No. 98-8] Proceedings of Mechanical Mechanics and Measurement Control

  However, in the configuration according to Japanese Utility Model Laid-Open No. 61-149854, in order to change the impact duration, it is necessary to disassemble the hammer and replace the head, which requires a large man-hour.

  Further, in the configuration according to Japanese Utility Model Laid-Open No. 3-6544, the impact member 120 is formed by connecting a plurality of members in the circumferential direction. Therefore, the impact is sustained when an impact is applied according to the rotation of the impact member 120. There is a problem that the time cannot be changed continuously. Moreover, since the striking member 120 is a composite body composed of a plurality of members, there is a problem that the manufacturing cost is increased.

  Therefore, a main object of the present invention is to provide an inexpensive impact test hammer which can change impact duration easily and continuously without requiring disassembly of the hammer.

  In order to solve the above-mentioned problems, an invention relating to an impact test hammer for applying an impact force to an object to be measured includes a head base and a portion that is provided so as to surround the outer periphery of the head base and is in contact with the object to be measured. The head having an impact portion whose rigidity varies depending on the circumferential shape, the upper and lower plate-like members sandwiching the head, and the head can be fixed to the plate-like member or the head can be rotated with respect to the plate-like member. And a support part having a head fixing part.

  According to the present invention, since the head can be freely rotated and supported by operating the head fixing portion, the impact duration can be changed easily and continuously without requiring disassembly of the hammer. Be able to.

It is a disassembled perspective view of the impact duration variable hammer which concerns on this embodiment. It is a perspective view of the impact part which goes round and becomes the minimum contact surface width from the maximum contact surface width. In cross-sectional view of the impact unit shown in FIG. 1, (a) is _R 1 = _{R 2} and _<a cross sectional view in the case of _{r 2,} (b) the _R 1> r 1 _{R 2 and, r} 1 = r it is a cross-sectional view of the case of _two. (A) shows the case where the maximum contact surface width and the minimum contact surface width are opposed to each other at a half circumference position, and (b) shows the maximum contact surface width and the minimum. It is a figure in case a contact surface width adjoins in one round position. It is the figure which showed the mode of the impact test. FIG. 6 is a frequency characteristic diagram illustrating a detection signal from a pickup, where (a) shows a large frequency peak value on the low frequency side and high frequency side, and (b) shows a frequency characteristic diagram when the peak value on the high frequency side is small. It is. It is a figure at the time of providing the scale in the head. It is a figure in the case of fixing a head with a clamp mechanism. FIG. 4A is a diagram of a head provided with slits. FIG. 5A is a top view when the slits are provided at an equal angle and the cut amount of each slit is changed. FIG. It is a top view at the time of making the cut amount of the same. It is a figure which shows a mode in the case of hanging a hammer with a wire etc. and impacting a to-be-measured object. It is a figure at the time of providing an actuator in a hammer. It is sectional drawing at the time of forming the convex part threaded by the center part of the head. It is a figure at the time of providing a head fixing screw in a head. It is a block diagram of the hammer used for the modal analysis experiment applied to description of related technology. It is a block diagram of the impact test hammer applied to description of related technology. It is a block diagram of the impact test hammer applied to description of related technology.

  An embodiment of the present invention will be described. FIG. 1 is an exploded perspective view of an impact duration variable hammer 2 according to the present embodiment. Hereinafter, the impact duration variable hammer 2 is abbreviated as a hammer 2.

  The hammer 2 includes a head 10, a support part 20, a sensor part 30, and a weight part 40, and gives an impact to the object to be measured. In addition, although various structures, such as a concrete wall, a bridge, a rocket, can be illustrated as a to-be-measured object, a concrete wall is made into an example below.

  The head 10 has a head base portion 11 and an impact portion 12. The head base portion 11 and the impact portion 12 are integrally formed or assembled using an elastic member such as rubber or resin so that the external appearance is generally a abacus ball shape. A rotation shaft hole 11 a corresponding to the shaft hole of the abacus ball is formed at the center of the head base 11. Hereinafter, although the external appearance shape of the impact part 12 is described as an abacus ball shape, it is not the meaning limited to the shape of an abacus ball.

  The outer surface of the impact portion 12 forms a contact surface that contacts the object to be measured when performing an impact test, and the width of the contact surface (the dimension in the axial direction of the rotation shaft hole 11a) is along the circumferential direction. It is changing continuously. Hereinafter, the width of the impact portion 12 (or the width of the contact surface) is referred to as the contact surface width.

  In FIG. 1, the impact portion 12 is formed to have a maximum contact surface width (dimension W1) at the point P1 and a minimum contact surface width (dimension W2) at the point P2, and the maximum contact surface width and the minimum contact surface width. The face width is opposed to the half circumference position. Of course, it may be configured to go from the maximum contact surface width to the minimum contact surface width by one round. FIG. 2 is a perspective view of the impact portion 12 that goes around the circle from the maximum contact surface width to the minimum contact surface width, and the maximum contact surface width and the minimum contact surface width are adjacent to each other.

FIG. 3 is a cross-sectional view of the impact portion 12 shown in FIG. 1. FIG. 3A shows a case where R ₁ = R ₂ and r ₁ <r ₂ (the positions of the impact points are the same and the positions of the centers of curvature are different). ), (B) are cross-sectional views when R ₁ > R ₂ and r ₁ = r ₂ (the positions of the impact points are different, but the positions of the centers of curvature are the same). Here, reference numeral O in the rotational axis of the impact section 12, K ₁ is the impact point of the maximum contact surface width, K ₂ is the impact point with a minimum contact surface width, O ₁ is the center of curvature of the maximum contact surface width , O ₂ is the center of curvature of the minimum contact surface width, R ₁ is the distance between the rotation axis O and the impact point K ₁ , R ₂ is the distance between the rotation axis O and the impact point K _2, and r ₁ is the rotation axis O. The distance from the center of curvature O ₁ , r ₂ is the distance between the rotation axis O and the center of curvature O ₂ .

  The shape of the impact portion 12 in the width direction of the contact surface is a curved surface. Since the impact portion 12 has a circular shape in the circumferential direction, the contact surface has a spherical shape. Therefore, the impact portion 12 having such a shape is referred to as a spherical impact type. When an impact is applied to the object to be measured, the impact portion 12 of the spherical impact type changes from point contact to surface contact. Thus, a desired impact force can be applied to the object to be measured regardless of the difference in the direction in which the impact is applied.

  Of course, the impact part 12 concerning this embodiment is not limited to a spherical impact type. For example, as shown in FIGS. 4A and 4B, a shape in which the shape of the impact portion 12 in the contact surface width direction is a plane (straight line) is also possible. Furthermore, the circumferential shape of the impact part 12 may be a polygon.

  FIG. 4A shows a configuration in which the maximum contact surface width and the minimum contact surface width face each other at a half circumference position (corresponding to the impact portion 12 shown in FIG. 1), and FIG. 4B shows the maximum contact surface width. The surface width and the minimum contact surface width are adjacent to each other at one round position (corresponding to the impact portion 12 shown in FIG. 2). It is described as a curved surface impact type having such a configuration. The impact portion 12 in the following will be described by taking the spherical impact type shown in FIG. 1 as an example.

  The support portion 20 has a configuration in which plate-like members 21a to 21c made of a metal having high rigidity such as iron are arranged so as to be substantially U-shaped in a side surface shape. The space formed by the plate-like members 21a to 21c forms the head storage portion 23, and the plate-like member 21a and the plate-like member 21b facing each other are provided with through holes 22 through which the head fixing portion 24 is inserted. Yes. In addition, as the head fixing | fixed part 24, the volt | bolt 24a and the nut 24b can be illustrated, for example, and it demonstrates in the following description as an example.

  Then, the head 10 is inserted into the head housing portion 23, and the bolts 24a are sequentially inserted through the through holes 22, the rotation shaft holes 11a, and the through holes 22 of the plate member 21b. Thereafter, the head 10 is fixed by screwing the nut 24b into the bolt 24a.

  The weight portion 40 is formed of a material having a high density such as iron on which an internal thread is formed, and includes a weight 41 having a predetermined weight, and a handle 42 on which a male thread that engages with the internal thread is formed at the tip. The inertia force of the hammer 2 is generated. Then, the operator gives an impact to the object to be measured by holding the handle 42 and shaking the hammer.

  The sensor unit 30 includes a load detector such as a load cell, and detects a force applied to the head 10 via the support unit 20 (reaction force when an object to be measured is impacted). The detected force is output as a load signal.

  Next, the operation | movement (usage form) of the hammer 2 of such a structure is demonstrated with an effect | action. FIG. 5 is a diagram showing a state of a modal analysis experiment for an object M such as a concrete wall. In this modal analysis experiment, the load signal from the sensor unit 30 of the hammer 2 is input to the frequency analyzer E. In addition, a pickup S such as an accelerometer is attached to the measurement object M so that vibration of the measurement object M can be detected. Note that the output of the pickup S is input to the frequency analyzer E as a detection signal.

  Then, the worker holds the handle 42, brings the impact portion 12 into contact with the object M to be measured, and gives an impact to the object M to be measured. At this time, even if the operator shakes the hammer 2 with the same force, the contact time (impact duration) between the impact portion 12 and the object M to be measured changes depending on the contact surface width dimension. Therefore, the head 10 is rotated and fixed around the bolt 24a as a rotation axis so that a desired impact duration can be obtained. Since the rigidity of the head 10 continuously changes along the circumference, the impact duration can also be set continuously.

  From the sensor unit 30 and the pickup S, detection signals that change periodically are output. FIGS. 6A and 6B are frequency characteristic diagrams illustrating detection signals from the pickup S. The vertical axis indicates acceleration and the horizontal axis indicates frequency. 6A is a frequency characteristic diagram when the peak values on the low frequency side and the high frequency side are large, and FIG. 6B is a frequency characteristic diagram when the peak value on the high frequency side is small.

  The load signal from the hammer 2 also has substantially the same waveform as the detection signal qualitatively. However, since the detection signal is measured by transmitting the impact force from the hit point to the pickup S, there is a difference in time lag and amplitude. Therefore, the difference (difference) between the load signal and the detection signal indicates vibration attenuation or resonance in the object to be measured.

  As described above, the size of the contact surface width in the impact portion 12 correlates with the impact duration. When the impact duration is short, the signal value on the low frequency side becomes small, and when the impact duration is long, the signal value on the high frequency side becomes small. 6A and 6B, the detection signal has peak values at a plurality of frequencies. As a test, it may be preferable to perform the test under an impact condition in which one peak value is sufficiently larger than the other peak values even for one peak or a plurality of peaks. For this purpose, it is necessary to select a contact position in the impact portion 12, but the impact condition is related to the structure and weight of the object to be measured and cannot be defined unconditionally.

  Therefore, the rotation position when the impact unit 12 is rotated to an arbitrary position is set as the test position, and the frequency characteristic diagram at that time is acquired as the test characteristic diagram (see FIG. 6A). Then, when it is desired to detect a signal on the low frequency side, an adjustment operation for obtaining the rotational position of the impact portion 12 is performed so that the peak value in the test characteristic diagram becomes smaller on the high frequency side (see FIG. 6B).

  The rotation position of the head 10 can be changed easily and reliably while the nut 24b is loosened and the head 10 is rotated and the nut 24b is tightened.

  Next, other embodiments 1 to 5 will be described. These embodiments are embodiments relating to the components of the above-described hammer, and exhibit their respective effects by replacing the corresponding components.

(Other embodiment 1)
In the configuration described so far, the impact portion 12 that changes the contact surface width is used to change the impact duration. Then, the impact duration was changed by loosening the nut 24b and rotating the head 10. At this time, since the rotational position depends on the subjectivity of the worker, it is expected that the reproducibility and the quantitativeness will be insufficient.

  In such a case, it is preferable to provide a scale 25 as shown in FIG. The scale 25 includes an index 25 a that is stamped or printed on the head base portion 11 and a scale 25 b that is stamped or printed on the impact portion 12. The rotational position of the impact portion 12 can be known from the position of the scale 25b indicated by the index 25a. At this time, it is also possible to cover the scale with a numerical value such as an angle. This makes it possible to perform tests with high reproducibility and quantitativeness.

(Other embodiment 2)
In the above description, the case where the head fixing portion 24 is constituted by the bolt 24a and the nut 24b is illustrated. And the impact part 12 was fixed by loosening the nut 24b, rotating the head 10, and fastening the said nut 24b.

  At this time, since the rotation direction of the nut 24b is parallel to the rotation surface of the head 10, the bolt 24a may be rotated by a force when the nut 24b is tightened. In such a case, it is preferable to restrict the rotation of the bolt 24a by fixing the bolt 24a to the plate-like member 21b.

  Further, if the head fixing portion 24 is composed of the bolt 24a and the nut 24b, there is an advantage that the cost is reduced. However, when the nut 24b is tightened, the nut tightening operation must be performed while supporting the head 10 so as not to rotate. Therefore, the case where the nut tightening operation is troublesome is assumed.

  In such a case, as shown in FIG. 8, a clamp handle 24c may be provided instead of the nut. The clamp handle 24c is pivotally fixed to the bolt 24a by a pin 24d. Then, by rotating the clamp handle 24c in the direction of arrow D, the plate-like member 21a and the plate-like member 21b are deformed, and the width of the head storage portion 23 (dimension in the direction of the head fixing portion) is reduced. To fix. In FIG. 8, the head 10 can rotate at the position of the clamp handle 24c indicated by the solid line, and the head 10 is fixed at the position indicated by the dotted line. Thereby, it can fix easily, without supporting the head 10, and workability | operativity improves.

(Other embodiment 3)
Furthermore, in the above description, in order to change the impact duration, the contact surface width of the impact portion 12 is changed. However, it is not limited to such a configuration. For example, a slit may be formed in the radial direction of the head 10 to change the rigidity of the head 10 in the circumferential direction. In this case, the slit and the surrounding head base 11 constitute the impact part 12.

  FIG. 9 is a top view of the head 10 provided with such a slit 13. 9A is formed such that the angles formed by the adjacent slits 13 are set to be equal angles, and the maximum cutting amount and the minimum cutting amount of the slits 13 are opposed to each other at a substantially half circumferential position of the head 10. (B) shows a case where a plurality of slits 13 are formed with the same cut amount, and the maximum angle and the minimum angle formed by the adjacent slits 13 are opposed to each other at a substantially half circumferential position of the head 10. Shows the case.

  In any configuration, since the rigidity of the head 10 changes depending on the interval and the cut amount of the slit 13, it is possible to obtain the same effect as when the contact surface width is changed.

(Other embodiment 4)
In the above embodiment, the operator grips the hammer 2 and gives an impact to the object M to be measured. In this case, there is an advantage that an impact can be easily given to an arbitrary place of the measurement object M.

  However, when the object to be measured M is a heavy object, it is assumed that the weight part 40 must also be heavy, so that it is difficult for the operator to grip and shake the hammer 2. In addition, since the detection signal includes information on the structure of the object to be measured M, the load applied to the object to be measured M must be accurately controlled when acquiring information on the structure with high accuracy. There is.

  In such a case, as shown in FIG. 10, it is preferable to hang the hammer 2 with the wire Z so as to give an impact to the object M to be measured. A dotted line in FIG. 10 corresponds to a state in which the hammer 2 is swung up, and a solid line represents a state in which the object to be measured M is given an impact by releasing the swung up hammer 2. Since the impact force can be set by the position where the hammer 2 is swung up, an accurate load can be applied to the object M to be measured.

(Other embodiment 5)
Further, as shown in FIG. 11, an actuator 50 that is operated by a working medium such as air may be provided, and the weight portion 40 may be inserted into the actuator 50. The actuator 50 includes a guide 51 into which the weight portion 40 is inserted, an input port 52 through which a working medium such as air flows, and an outflow port 53 through which the working medium flows out.

When the working medium flows in a state in which the weight portion 40 is inserted into the guide 51, the weight portion 40 receives a propulsive force and comes into contact with the object to be measured M while being guided by the guide 51. At this time, it is preferable that the head 10 abuts perpendicularly to the abutment surface (excitation surface) of the object M to be measured.

Since the inflow amount (including speed) of the working medium can be controlled in advance, the same impact force can be applied to the object to be measured even when the test is repeatedly performed, and the measurement reliability is improved. improves. The impact force is a force in the direction when the weight portion 40 is guided by the guide 51.

(Other embodiment 6)
In the above description, in the head 10, the head base 11 and the impact portion 12 are integrally formed, and the rotation shaft hole 11 a is provided in the head base 11. And it was the structure which inserts the volt | bolt 24a in the rotating shaft hole 11a, and pinches | interposes with plate-shaped member 21a, 21b. However, the present invention is not limited to such a configuration. For example, as shown in FIG. 12, the head base 11 or a part thereof is formed of metal, hard resin, or the like, and a convex portion 11b that is threaded at the center is formed. Also good. In this case, the head fixing portion 24 includes the convex portion 11b.

(Other embodiment 7)
Moreover, in 1st Embodiment, it was the structure which regulates the rotation of the head 10 by adjusting the space | interval of the plate-shaped member 21a and the plate-shaped member 21b by tightening the nut 24b strongly. However, as shown in FIG. 13, a head fixing screw 26 for restricting the rotation of the head 10 may be provided separately. In this case, the head fixing portion 24 includes a head fixing screw 26. With such a configuration, the head 10 can be reliably fixed without strongly tightening the nut 24b.

  A part or all of the above embodiment can be described as in the following supplementary notes, but is not limited thereto.

<Appendix 1>
An impact test hammer that applies impact force to the object to be measured,
A head base, and a head having an impact portion that is provided so as to surround the outer periphery of the head base, and in which the rigidity of the portion that comes into contact with the object to be measured varies depending on the circumferential shape;
Upper and lower plate-like members that sandwich the head, and a support portion having a head fixing portion that fixes the head to the plate-like member or allows the head to rotate with respect to the plate-like member; ,
An impact test hammer characterized by comprising:

<Appendix 2>
An impact test hammer according to appendix 1,
At least one of the contact surface width in the impact portion or the thickness of the radial portion following the contact surface is formed to have different dimensions in the circumferential direction, and the rigidity of the impact portion is changed in the circumferential direction. Impact test hammer.

<Appendix 3>
The impact test hammer according to appendix 1 or appendix 2,
The impact part is
An impact test hammer, wherein the impact test hammer is formed with a predetermined curvature in the contact surface width direction, and the rigidity of the impact portion is changed in the circumferential direction by the curvature being different in the circumferential direction.

<Appendix 4>
The impact test hammer according to appendix 2 or 3,
An impact test hammer characterized in that the maximum value and the minimum value of the contact surface width at the impact portion are opposed to each other at a half circumference position of the head.

<Appendix 5>
The impact test hammer according to appendix 2 or 3,
An impact test hammer characterized in that a maximum value and a minimum value of the contact surface width at the impact portion are adjacent to each other at one circumference of the head.

<Appendix 6>
An impact test hammer according to appendix 1,
An impact test hammer characterized in that a plurality of slits are formed in the radial direction of the head to change the rigidity of the impact portion in the circumferential direction.

<Appendix 7>
The impact test hammer according to appendix 6,
An impact test hammer characterized in that the angle formed by adjacent slits is set to an equal angle, and the slits are formed so that the amount of cut is different in the circumferential direction.

<Appendix 8>
The impact test hammer according to appendix 6,
An impact test hammer characterized in that a plurality of slits are formed with the same cut amount, and the angles formed by adjacent slits are different in the circumferential direction.

<Appendix 9>
The impact test hammer according to any one of appendices 1 to 8,
A scale is provided in the impact part, and an index indicating the position of the scale is provided in the support part.
An impact test hammer characterized in that the rotational position of the head can be determined from the scale position indicated by the index.

<Appendix 10>
The impact test hammer according to any one of appendices 1 to 9,
An impact test hammer characterized in that a head fixing portion for adjusting a distance between plate-like members is formed by a bolt and a nut or a bolt and a clamp handle.

<Appendix 11>
The impact test hammer according to any one of appendices 1 to 10,
An impact test hammer having a guide hole into which an impact test hammer is inserted, and an actuator that generates an impact force along the axis of the guide hole by pushing the impact test hammer with a working medium .

<Appendix 12>
The impact test hammer according to any one of appendices 1 to 11,
An impact test hammer characterized in that a sensor unit for measuring an impact force applied to an object to be measured is provided.

<Appendix 13>
The impact test hammer according to any one of appendices 1 to 12,
An impact test hammer characterized in that a weight having a predetermined weight is provided so that an impact force due to a large inertial force is applied to an object to be measured.

2 Impact duration variable hammer 10 Head 11 Head base 11a Rotating shaft hole 12 Impact part 13 Slit 20 Support part 21a-21c Plate member 22 Through hole 23 Head storage part 24 Head fixing part 24a Bolt 24b Nut 24c Clamp handle 24d Pin 25 Scale 25a Index 25b Scale 26 Head fixing screw 30 Sensor part 40 Weight part 41 Weight 42 Handle 50 Actuator

Claims (9)

An impact test hammer that applies impact force to the object to be measured,
A head base, and a head having an impact portion that is provided so as to surround the outer periphery of the head base, and in which the rigidity of the portion that comes into contact with the object to be measured varies depending on the circumferential shape;
Upper and lower plate-like members that sandwich the head, and a support portion having a head fixing portion that fixes the head to the plate-like member or allows the head to rotate with respect to the plate-like member; ,
Equipped with a,
At least one of the contact surface width or the radial thickness following the contact surface in the impact portion is formed to have different dimensions in the circumferential direction, and the rigidity of the impact portion is changed in the circumferential direction. Impact test hammer. The impact test hammer according to claim 1 ,
The impact part is
An impact test hammer, wherein the impact test hammer is formed with a predetermined curvature in the contact surface width direction, and the rigidity of the impact portion is changed in the circumferential direction by the curvature being different in the circumferential direction. The impact test hammer according to claim 1 or 2 ,
An impact test hammer characterized in that a maximum value and a minimum value of rigidity at an impact portion are formed to face each other at a half circumference position of the head. The impact test hammer according to claim 1 or 2 ,
An impact test hammer characterized in that a maximum value and a minimum value of rigidity at an impact part are formed adjacent to each other at a position around the head. The impact test hammer according to claim 1,
An impact test hammer characterized in that a plurality of slits are formed in the radial direction of the head to change the rigidity of the impact portion in the circumferential direction. The impact test hammer according to claim 5 ,
An impact test hammer characterized in that the angle formed by adjacent slits is set to an equal angle, and the slits are formed so that the amount of cut is different in the circumferential direction. The impact test hammer according to claim 5 ,
An impact test hammer characterized in that a plurality of slits are formed with the same cut amount, and the angles formed by adjacent slits are different in the circumferential direction. The impact test hammer according to any one of claims 1 to 7 ,
A scale is provided in the impact part, and an index indicating the position of the scale is provided in the support part.
An impact test hammer characterized in that the rotational position of the head can be determined from the scale position indicated by the index. The impact test hammer according to any one of claims 1 to 8 ,
An impact test hammer having a guide hole into which an impact test hammer is inserted, and an actuator that generates an impact force along the axis of the guide hole by pushing the impact test hammer with a working medium .

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