JP5440517B2 - Material testing machine - Google Patents

Description

  The present invention relates to a material testing machine that performs a tensile test, a compression test, and a torsion test on a test piece.

  A material testing machine that performs a tensile test or the like on a test piece constitutes a load frame by, for example, a table, a pair of support columns erected on the table, and a crosshead connected via the support columns. . The crosshead can be moved up and down along the column by an actuator or the like, and the test piece is gripped at both ends by an upper gripping tool disposed on the crosshead and a lower gripping tool disposed on the table. The test force and displacement at that time are measured by the load cell and displacement detector while applying a load by raising and lowering the cross head to the test piece gripped at both ends by the upper gripper and the lower gripper. The test force-displacement characteristic of the test piece and the SN diagram are obtained. In such a material testing machine, an accurate material test cannot be performed unless the axes of the upper gripper and the lower gripper are aligned. For this reason, in such a material testing machine, a shaft center adjusting device for adjusting the shaft centers of the upper gripping tool and the lower gripping tool is provided.

  FIG. 7 is a schematic view of the vicinity of the axis adjusting device 113 in the conventional material testing machine.

  The shaft center adjusting device 113 is interposed between the cross head 23 and the upper gripper, and includes a connecting shaft 131 that connects the crosshead 23 and the upper gripper via the connecting portion 111, and the connection shaft 131. A frame member 139 fixed to the center of the shaft 131, an angle adjusting collar member 134 disposed on the outer periphery of the connecting shaft 131 inside the frame member 139 and fixed to the crosshead 23, and the frame member 139 The position adjusting collar member 135 is provided on the outer periphery of the connecting shaft 131 and fixed to the connecting portion 111.

  The connecting shaft 131 passes through the angle adjusting collar member 134, the frame member 139, and the position adjusting collar member 135, and the upper end portion of the connecting shaft 131 is screwed with the mounting plate 132. Is screwed to the connecting portion 111. The mounting plate 132 is connected to the cross head 23 via a pair of jack bolts 133. For this reason, by moving the mounting plate 132 upward with respect to the cross head 23 using a pair of jack bolts 133, the upper gripping tool disposed at the lower end of the connecting portion 111 is moved with a predetermined force. Can be fastened.

  The frame member 139 includes a support portion 137 that is screwed and fixed to the connecting shaft 131, and a rectangular frame portion 136 that surrounds the connecting shaft 131. A hemispherical convex portion 138 is formed on the upper surface of the support portion 137, and a hemispherical concave portion having a shape corresponding to the convex portion 138 is formed on the lower surface of the angle adjusting collar member 134. Further, the lower surface of the support portion 137 has a planar shape, and is in contact with the upper surface of the planar position adjusting collar member 135.

  FIG. 8 is a schematic plan view of the vicinity of the angle adjusting collar member 134 in the shaft center adjusting device 113.

  The angle adjusting collar member 134 has a rectangular shape or a circular shape in plan view, and its outer peripheral surface has four screws 141, 142, 143, which are screwed with the frame portion 136 of the frame member 139. 144 is in contact with the tip of 144. For this reason, by adjusting the four screws 141, 142, 143, and 144, the frame member 139 can be tilted together with the connecting shaft 131 to adjust the angle of the upper gripping tool. That is, of the four screws 141, 142, 143, 144, one of the two screws facing each other is loosened and the other is tightened, and the hemispherical convex portion 138 of the frame member 139 is moved to the angle adjusting collar member. The frame member 139 can be tilted together with the connecting shaft 131 by being moved along the hemispherical concave portion 134. As the connecting shaft 131 is inclined, the upper gripping tool is inclined.

  FIG. 9 is a schematic plan view of the vicinity of the position adjusting collar member 135 in the shaft center adjusting device 113.

  The position adjusting collar member 135 has a rectangular shape or a circular shape in plan view, and its outer peripheral surface has four screws 151, 152, 153, which are screwed with the frame portion 136 of the frame member 139. 154 is in contact with the tip of 154. For this reason, by adjusting the four screws 151, 152, 153, 154, the frame member 139 can be moved together with the connecting shaft 131 to adjust the position of the upper gripper. That is, of the four screws 151, 152, 153, 154, the frame member 139 is moved along the upper surface of the position adjusting collar member 135 in a state where one of the two screws facing each other is loosened and the other screw is tightened. By doing so, the frame member 139 can be moved relative to the position adjusting collar member 135 together with the connecting shaft 131. As the connecting shaft 131 moves, the upper gripper also moves.

  By the way, the material test by the material testing machine provided with the shaft center adjusting device 113 is a tensile test or a compression test that applies a load only in the vertical direction to the test piece, and a torsion test that applies a torsional load to the test piece. Is not supported. In addition, as a material testing machine that can cope with a torsion test, a machine in which a rotation stop plate is attached as a bending moment removing jig on a side surface of a portion corresponding to an axis adjusting device has been proposed (see Patent Document 1). .

Japanese Patent Laid-Open No. 3-82933

  The reason why the material testing machine including the above-described shaft center adjusting device 113 cannot cope with the torsion test in which a torsional load is applied to the test piece is as follows. In the case of a test in which a torsional load is applied to a test piece, unlike the case of a tensile test in which a load is applied only in the vertical direction to the test piece, the upper gripping tool, the shaft center adjustment device 113, etc. A torsional load is applied. For the torsional load applied at this time, the frictional force between the concave portion of the angle adjusting collar member 134 and the convex portion 138 of the frame member 139 in the shaft center adjusting device 113 and the position adjusting collar member 135 This is countered by the frictional force between the upper surface and the lower surface of the support portion 137 of the frame member 139.

  The frictional force between the concave portion of the angle adjusting collar member 134 and the convex portion 138 of the frame member 139 in the shaft center adjusting device 113, and the upper surface of the position adjusting collar member 135 and the lower surface of the support portion 137 of the frame member 139 The frictional force between the two can be increased by increasing the force of pulling up and fastening the upper gripping tool by the pair of jack bolts 133. However, since the axis adjustment device 113 performs the axis adjustment by moving the angle adjustment collar member 134 and the position adjustment collar member 135 relative to the frame member 139, the angle adjustment collar member The frictional force between the concave portion 134 and the convex portion 138 of the frame member 139 and the frictional force between the upper surface of the position adjusting collar member 135 and the lower surface of the support portion 137 of the frame member 139 counteract the torsional load. It can't be as big as possible. For this reason, in the material testing machine provided with the shaft center adjusting device 113, the shaft center adjusting device 113 cannot cope with the torsional load, so that the torsion test for applying the torsional load to the test piece cannot be performed.

  On the other hand, in order to counter the torsional load, when the upper gripping tool connected to the shaft center adjusting device 113 receives the torsional load, in order to prevent the torsional load from reaching the shaft center adjusting device 113, for example, a crosshead It is conceivable to fix the upper gripping tool to 23 via some member. However, if all such members are made of a material having high rigidity, for example, even if the shaft center is adjusted first, the fixed position of the upper gripper is determined at a predetermined position due to the rigidity of the member. The problem is that the adjustment becomes meaningless. Further, in the above-described axial center adjusting device 113, the axial center adjusting screws 141, 142, 143, 144, 151, 152, 153, 154 are the outer peripheral surfaces of the angle adjusting collar member 134 and the position adjusting collar member 135. It is arranged. For this reason, on the side surface of the shaft center adjusting device 113, a space where the operator can easily access the screws 141, 142, 143, 144, 151, 152, 153, 154 for shaft center adjustment must be secured. A member that covers most of the side surfaces of the shaft center adjusting device 113 cannot be adopted as a member that fixes the upper gripping tool to the crosshead 23.

  The present invention has been made to solve the above-described problems, and provides a material testing machine that includes an axis adjustment unit that adjusts the axis, and that can adjust the torsional load. For the purpose.

  The invention according to claim 1 is a material testing machine for performing a tensile / compression test and a torsion test on a test piece held by a pair of grips, and is fixed to a load frame, and the pair of grips. An axial center adjusting portion that adjusts the axis of the gripping tool by being connected to one of the tools via a connecting portion, and a gripping tool that is fixed to the connecting portion and connected to the axial center adjusting portion. And a deformable plate member arranged in a direction in which the surface intersects with the connecting direction of the shaft center adjusting portion, and a plurality of support members that connect the plate member and the load frame. It is characterized by.

  According to a second aspect of the present invention, in the first aspect of the present invention, the plate member and the plurality of support members are connected via a fastening member, and the fastening member is inserted into the plate member. A plurality of insertion holes are provided, and the insertion holes are larger than the outer diameter of the fastening member.

  The invention according to claim 3 is the invention according to claim 2, wherein the plate member is a single metal thin plate having a connection hole through which the connection portion passes.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, the thin plate has a plurality of notches in the vicinity of the connecting hole.

  According to a fifth aspect of the present invention, in the second aspect of the present invention, the plate member is a plurality of metal thin plates disposed at equal intervals around the connecting portion.

  According to a sixth aspect of the present invention, in the first aspect of the present invention, the connecting portion includes a load detection unit that detects a test force applied to the test piece.

  The invention according to claim 7 is the load cell according to claim 6, wherein the load detecting means is a load cell capable of simultaneous biaxial measurement.

  According to invention of Claim 1, while being fixed to a connection part, it is arrange | positioned in the direction which the surface cross | intersects with respect to the connection direction of the holding tool connected to the axial center adjustment part, and an axial center adjustment part. And a plurality of support members that connect the plate member and the load frame, so that the gripper can be loaded on a load such as a crosshead without affecting the axis adjustment by the axis adjustment unit. It can be fixed to a member constituting the frame. Accordingly, even when a torsional load is applied to the test piece, the shaft center adjusting portion and the gripping tool connected to the shaft center adjusting portion can be prevented from rotating during the test.

  According to the invention described in claim 2, since the insertion holes of the plurality of fastening members provided in the plate member for connection with the support member are larger than the outer diameter of the fastening member, The plate member can be moved horizontally with respect to the inclination direction of the gripping tool determined by adjusting the heart, and the gripping tool is fixed to a member constituting a load frame such as a crosshead while maintaining the tilting direction of the gripping tool. be able to.

  According to the invention described in claim 3, since the plate member is a single thin plate made of metal having a connection hole through which the connection portion passes, the device configuration that can easily counter the torsional load with a small number of parts is provided. can do.

  According to the invention described in claim 4, since the thin plate has a plurality of notches in the connection hole, the thin shape of the connection hole can be prevented from deforming the connection hole due to the outer surface of the connection shaft coming into contact with the inner peripheral surface of the connection hole. It is possible to prevent the entire thin plate from being distorted.

  According to invention of Claim 5, since a board member is a some metal thin board arrange | positioned at equal intervals centering on a connection part, attachment can be performed easily.

  According to the invention described in claim 6, since the load detecting means for detecting the test force applied to the test piece is provided in the connecting portion, when performing a fatigue test that repeats tension and compression on the test piece. The test force applied to the test piece can be accurately detected.

  According to the seventh aspect of the present invention, since the load detecting means is a load cell capable of two-axis simultaneous measurement, the test force by the tension / compression in the vertical direction with respect to the test piece and the rotation direction with respect to the test piece 10 are measured. Both test force by torsion can be measured simultaneously. For this reason, the test force in the test combining the torsion test with the tension / compression test can also be detected.

1 is a schematic diagram of a material testing machine according to the present invention. It is a schematic diagram of the shaft center adjustment device 13 vicinity. 4 is a plan view of a thin plate 60. FIG. It is a top view of the other thin plate 80. FIG. It is a top view of the other thin plate 90. FIG. FIG. 5 is a schematic view of the vicinity of a support member 70. It is a schematic diagram of the shaft center adjustment device 113 vicinity in the conventional material testing machine. 5 is a schematic plan view of the vicinity of an angle adjusting collar member in the shaft center adjusting device 113. FIG. FIG. 6 is a schematic plan view of the vicinity of a position adjusting collar member 135 in an axis adjusting device 113.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a material testing machine according to the present invention.

  In this material testing machine, a load frame is configured by a table 16, a pair of support columns 14 erected on the table 16, and a crosshead 23 horizontally mounted on the pair of support columns 14, and is connected to the crosshead 23. A pair of hydraulic cylinders 15, a linear actuator 25 and a torque actuator 26 are provided.

  The table 16 is provided with a lower grip 12 for gripping the lower end of the test piece 10. The lower grip 12 is connected to the linear actuator 25 and the torque actuator 26 through a shaft 27 that passes through the table 16. The linear actuator 25 functions as power that applies a vertical load to the test piece 10 by applying a vertical force to the lower grip 12 that repeats tension and compression performed in a fatigue test or the like. The torque actuator 26 is supported on a base frame 29 under the table 16 by a support plate 28, and functions as power for applying a torsional load to the test piece 10 by applying a rotational force to the lower gripping tool 12. To do. The support plate 28 is disposed so as to be movable up and down with respect to the base frame 29.

  The crosshead 23 is provided with an upper gripper 11 for gripping the upper end of the test piece 10 via an axis adjustment device 13 as an axis adjustment unit and a load cell 24 as a load measurement unit. The cross head 23 moves up and down along the pair of columns 14 by the expansion and contraction of the pair of hydraulic cylinders 15. Thereby, a vertical load such as tension or compression is applied to the test piece 10 held at both ends by the upper grip 11 and the lower grip 12.

  The load cell 24 is a so-called biaxial load cell capable of simultaneously measuring both the test force in the vertical direction with respect to the test piece 10 and the test force in the rotational direction with respect to the test piece 10. Therefore, the test force can be detected not only in a tensile test, a compression test, and a torsion test, but also in a test in which a torsion test is combined with a tensile / compression test.

  FIG. 2 is a schematic view of the vicinity of the shaft center adjusting device 13.

  The shaft center adjusting device 13 is interposed between the cross head 23 and the upper gripping tool 11, and includes a connecting shaft 131 that connects the crosshead 23 and the connecting portion 61 connected to the upper gripping tool 11, A frame member 139 fixed to the center portion of the connecting shaft 131, an angle adjusting collar member 134 disposed on the outer peripheral portion of the connecting shaft 131 inside the frame member 139 and fixed to the crosshead 23, and a frame member 139 is provided on the outer periphery of the connecting shaft 131 inside the connecting shaft 131, and is provided with a position adjusting collar member 135 fixed to the connecting portion 61. In addition, about the structure similar to the conventional axial center adjustment apparatus 113 shown in FIGS. 7-9, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  In this material testing machine, since the load cell 24 is further interposed between the upper gripper 11 and the shaft center adjusting device 13, the lower end of the connecting shaft 131 is different from the conventional shaft center adjusting device 113 and the load cell. 24 and the connecting part 61 with the screw 24. As described above, the connecting portion 61 is not directly connected to the upper gripper 11, but when the load cell 24 is disposed on the lower gripper 12 side, Similarly, the connecting portion 61 is connected to the upper gripper 11.

  In this material testing machine, a thin plate 60 and a support member 70 for fixing the upper grip 11 connected to the connecting portion 61 via the load cell 24 to the cross head 23 by connecting the connecting portion 61 to the cross head 23. With. The thin plate 60 is connected to the lower end of the support member 70 by a screw 62 that is a fastening member, and is fixed to the connecting portion 61 by a screw. In addition, four support members 70 are arranged so as to form a space where the operator can access the screws 141, 142, 143, 144, 151, 152, 153, 154 for adjusting the shaft center. The upper end is fixed to the crosshead 23 with screws.

  7, the connecting shaft 131 penetrates the angle adjusting collar member 134, the frame member 139, and the position adjusting collar member 135, and the upper end portion of the connecting shaft 131. Is screwed with the mounting plate 132, and the lower end portion of the connecting shaft 131 is screwed with the connecting portion 61. The mounting plate 132 is connected to the cross head 23 via a pair of jack bolts 133. For this reason, by using the pair of jack bolts 133 to move the attachment plate 132 upward with respect to the cross head 23, the upper grip 11 disposed at the lower end of the connecting portion 61 via the load cell 24 is predetermined. It can be fastened to the crosshead 23 with the force of

  FIG. 3 is a plan view of the thin plate 60.

  The thin plate 60 is formed of a single disk-shaped metal plate that has little rigidity in the tilt direction of the upper gripping tool 11. That is, the thin plate 60 can be flexibly deformed corresponding to the inclination of the upper gripper 11 with respect to the bending force directed toward the surface of the thin plate 60. The thin plate 60 is provided with a connecting hole 65 for inserting the connecting portion 61 at the center, and a plurality of screws for fixing the thin plate 60 to the flange portion 64 of the connecting portion 61 along the connecting hole 65 with screws. A hole 66 is provided. The connection hole 65 has a plurality of notches 67 for preventing deformation caused by a part of the outer peripheral surface of the connection part 61 coming into contact with the connection hole 65 and the entire connection hole 65 and the entire thin plate 60. Is formed. The number of notches 67 in the connecting hole 65 and the number of screw holes 66 formed along the connecting hole 65 are not limited to those shown in FIG. That's fine.

  Further, the thin plate 60 is provided with a plurality of insertion holes 68 for connecting the thin plate 60 and the lower end of the support member 70 along the outer periphery of the disk. In this material testing machine, as will be described later, since four support members 70 whose lower ends are fixed by two screws 62 are arranged, the insertion hole 68 is formed at the lower end of the support member 70. The number corresponding to the screw holes for connection with the thin plate 60, that is, eight is formed. The diameter of the insertion hole 68 is larger than the outer diameter of the screw 62 inserted into the insertion hole 68 and smaller than the head diameter of the screw 62. Thus, by making the insertion hole 68 larger than the outer diameter of the screw 62 inserted therein, the thin plate 60 can be moved in the horizontal direction in accordance with the inclination of the upper gripping tool 11. The thin plate 60 is provided with a notch 69 along the outer periphery of the disk. However, since the outer periphery of the thin plate 60 is not arranged to contact other members, the notch 69 is not provided. May be.

  4 and 5 are plan views of other thin plates 80 and 90. FIG. In addition, about the structure same as the thin plate 60 demonstrated previously, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

  The thin plate 80 shown in FIG. 4 is formed of a single metal plate similar to the thin plate 60 described above, but unlike the thin plate 60, the cutout portion is formed on either the connection hole 85 or the outer periphery of the disk. Also not formed. In the case where there is no problem such as deformation of the entire connecting hole 85 and the entire thin plate 80 due to contact with other members, the notch portion may be omitted as in the thin plate 80.

  Unlike the thin plate 60 described above, the thin plate 90 shown in FIG. 5 is formed of four substantially fan-shaped flexible metal plates. In this material testing machine, since four support members 70 are disposed, one thin plate 90 is disposed for each support member 70. Note that the number of thin plates is not limited to the number corresponding to the number of support members 70, and for example, approximately semicircular thin plates may be provided for the two support members 70. Further, the shape of the thin plate 90 is not limited to a substantially fan shape, and may be a trapezoidal shape, for example.

  FIG. 6 is a schematic view of the vicinity of the support member 70.

  The support member 70 is a metal columnar member having a substantially I-shape when viewed from the front and having high rigidity. The upper end of the support member 70 is fixed to the cross head 23 by two screws 72. A screw hole corresponding to two screws 62 is provided at the lower end of the support member 70, and the thin plate 60 is fixed to the support member 70 by fastening the screws 62.

  With reference to FIG. 2 again, the shaft center adjustment in this material testing machine will be described. First, in a state where the test piece 10 is gripped by the upper gripping tool 11 and the lower gripping tool 12, the screws 62 that connect the thin plate 60 and the plurality of support members 70 are loosened so as not to fall off. At this time, since the diameter of the insertion hole 68 is larger than the outer diameter of the screw 62, the thin plate 60 can move horizontally by the size of the insertion hole 68. In this state, the operator adjusts the shaft center by operating the screws 141, 142, 143, 144 for angle adjustment and the screws 151, 152, 153, 154 for position adjustment in the shaft center adjusting device 13. .

  When the axial center adjustment is completed, the operator tightens the screw 62 and fixes the thin plate 60 to the support member 70. At this time, since the diameter of the insertion hole 68 is larger than the outer diameter of the screw 62, the shaft of the screw 62 and the center of the insertion hole 68 are aligned in accordance with the inclination of the upper gripper 11 by adjusting the shaft center first. Even in the shifted state, the screw 62 can be tightened. Further, even when the gap between the lower end surface of the support member 70 and the surface of the thin plate 60 is not uniform due to the inclination of the upper gripper 11, the thin plate 60 is flexible with respect to the force applied to the surface. Therefore, the thin plate 60 is deformed when the screw 62 is fastened. Thus, the upper gripper 11 is fixed to the cross head 23 without giving the shaft center adjusting device 13 a force that increases the frictional force between the members in the shaft center adjusting device 13 when the screws 62 are fastened. Can do.

  As described above, when the upper gripping tool 11 is fixed to the cross head 23, when the torsional load is applied to the test piece 10, the upper gripping tool 11 does not rotate in the rotational direction of the torsional load, and the connecting shaft 131 moves upward. It does not rotate with the gripper 11. Therefore, it is possible to prevent the shaft center adjusting device 13 from rotating.

  In the embodiment described above, since the shaft center adjusting device 13 and the load cell 24 are interposed between the cross head 23 and the upper gripping tool 11 constituting the load frame, the connecting portion 61 is connected to the shaft center adjusting device 13. However, the connecting portion of the present invention may be any member that connects the load frame and one of the pair of gripping tools.

DESCRIPTION OF SYMBOLS 10 Test piece 11 Upper grip 12 Lower grip 13 Axis center adjustment device 14 Support | pillar 15 Hydraulic cylinder 16 Table 23 Crosshead 24 Load cell 25 Linear actuator 26 Torque actuator 27 Shaft 28 Support plate 29 Base frame 60 Thin plate 61 Connection part 62 Screw 64 Flange portion 65 Connection hole 66 Screw hole 67 Notch portion 68 Insertion hole 70 Support member 80 Thin plate 90 Thin plate 111 Connection portion 131 Connection shaft 132 Mounting plate 133 Jack bolt 134 Angle adjustment collar member 135 Position adjustment collar member 136 Frame portion 137 Support part 138 Convex part 139 Frame member 141 Screw 142 Screw 143 Screw 144 Screw 151 Screw 152 Screw 153 Screw 154 Screw

Claims (7)

A material testing machine for performing a tensile / compression test and a torsion test on a test piece held by a pair of gripping tools,
An axial center adjustment unit that is fixed to the load frame and is connected to one of the pair of gripping tools via a connection portion, thereby adjusting the axial center of the gripping tool;
A deformable plate member that is fixed to the connecting portion and is disposed in a direction in which the surface intersects the connecting direction of the gripper connected to the shaft center adjusting portion and the shaft center adjusting portion,
A plurality of support members connecting the plate member and the load frame;
A material testing machine comprising: The material testing machine according to claim 1,
The plate member and the plurality of support members are coupled via a fastening member,
The plate member is provided with a plurality of insertion holes for inserting the fastening members,
The insertion hole is a material testing machine larger than the outer diameter of the fastening member. The material testing machine according to claim 2,
The said plate member is a material testing machine which is a metal thin plate which has a connection hole which the said connection part penetrates. The material testing machine according to claim 3,
The thin plate is a material testing machine having a plurality of notches in the vicinity of the connection hole. The material testing machine according to claim 2,
The said board member is a material testing machine which is a some metal thin board arrange | positioned at equal intervals centering on the said connection part. The material testing machine according to claim 1,
A material testing machine comprising load detecting means for detecting a test force applied to the test piece at the connecting portion. The material testing machine according to claim 6,
The load detecting means is a material testing machine which is a load cell capable of two-axis simultaneous measurement.

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