JP2000193573A - Torsion tester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a torsion tester having simple and compact constitution as compared with a conventional torsion tester and capable of being easily mounted on a general-purpose material tester to apply torsional torque to a test piece. SOLUTION: In the torsion tester, a gripper 13 on a rotary side and a load pulley 18 are fixed to the freely revolvable rotary shaft 15 on a base plate 11 and the wire 19 stretched over the load pulley 18 is vertically extended to engage the leading end of the wire with the load cell 25 mounted on a material tester. The linear motion of the moving member such as the crosshead 24 of the material tester is converted into rotary motion by the load pulley 18 and the wire 19 and rotatory force is applied to the gripper 13 on the rotary side and torque is applied to the test piece W held between the gripper 13 and the gripper 14 on a fixed side arranged opposedly to the gripper 13 and this torque is calculated on the basis of the product of the output of the load cell 25 and the radius of the load pulley 18. By this constitution, the function on the side of the material tester is effectively utilized to dispense with an exclusive drive source and a torque cell.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torsional test apparatus, and more particularly, to a torsional test apparatus which is mounted on a material testing machine provided with a moving member such as a crosshead that makes a linear motion to apply a tensile load to a test piece. And a torsion test apparatus capable of performing a torsion test by driving the material testing machine.

[0002]

2. Description of the Related Art A torsional moment T is applied to a test piece,
The resulting twist angle θ of the sample was measured and
In a torsion test for obtaining a θ curve or a desired torque T-time curve or the like, generally, a rotational force for applying a torsional moment to one end of a test piece is applied to the other end.

As a device for performing such a torsion test, a device mounted on a general-purpose material tester and used is conventionally known. That is, a general-purpose material testing machine generally includes a moving member such as a crosshead that moves up and down so as to approach and separate from a fixed member such as a table, and the test piece is moved linearly by the moving member. It is configured to apply a tensile load, etc. to the material tester, but as a conventional torsion tester that can be mounted on such a material tester to perform a torsion test of the test piece, a separately prepared rotary drive source and Is placed adjacent to the material testing machine, and on the table of the material testing machine, the rotating grip (test piece holding unit) and the rotation of the motor with respect to the rotating grip are held. There is known a configuration in which a transmission speed reduction mechanism is provided, and a fixed gripper (test piece holding unit) and a torque cell are provided on the lower surface of the crosshead. And
When performing a torsional test, the crosshead is moved up and down to set the distance between the gripper on the rotating side and the fixed side, and then the crosshead is fixed and the rotating side is driven via a deceleration mechanism by driving a separate motor. A torque is applied to the gripper, and the torque cell measures the momentary torque acting on the test piece.

[0004]

By the way, in the conventional torsion test apparatus as described above, a large torque is applied to the test piece in order to greatly reduce the rotation of the motor and transmit it to the rotary gripper. Although it is possible to do so, not only a separate motor is required, but also a special deceleration mechanism and a torque cell are required, and there is a problem that the device is complicated and large.

SUMMARY OF THE INVENTION An object of the present invention is to provide a general-purpose material testing machine which has the same performance as a conventional torsion testing apparatus in a simple and compact configuration as compared with the conventional torsion testing apparatus. It is an object of the present invention to provide a torsion test device that can be easily attached and detached.

[0006]

In order to achieve the above object, a torsion test apparatus according to the present invention includes a moving member that linearly moves toward and away from a fixed member, and the moving member moves linearly. A torsion test apparatus used by being attached to a material testing machine configured to apply a load to a test piece by a load cell provided on a fixed member or a moving member and to apply a load to the test piece. A base plate fixed to the fixed member or the moving member, a rotating shaft rotatably supported on the base plate so as to be orthogonal to the moving direction of the moving member, and a rotation fixed to the rotating shaft. Side test piece holder, fixed side test piece holder provided on the base plate opposite to the rotating side test piece holder,
A load pulley fixed to the rotating shaft, a wire having one end attached to the load pulley and the other end attached to a load sensitive portion of the load cell is wound around the load pulley; It is characterized by being configured to convert the linear motion of the moving member into the rotary motion of the rotating test piece holder by the load pulley.

[0007] The present invention provides a motor, a speed reduction mechanism, a torque, and a dedicated motor for applying a rotational force to a rotating test piece holder by effectively utilizing the functions of a general-purpose material testing machine. The purpose of the present invention is to achieve the intended purpose by eliminating the need for a torque cell for measuring the torque.

That is, in the torsion test apparatus of the present invention,
A load cell for converting the linear motion of a moving member such as a crosshead in a general-purpose material testing machine into the rotational motion of a rotating shaft by a load pulley and a wire to apply a torsional torque to a test specimen and measure a tensile load. The output of allows the torque applied to the test piece to be measured.

Here, in a general-purpose material testing machine,
The load cell is provided on either the moving member or the fixed member. In the torsion test device of the present invention, the base plate is fixed to the member on the side of the moving member and the fixed member to which the load cell is not attached, and the load cell is mounted on the base plate. Then, the load pulley and the rotating test piece holder are fixed to the rotatable rotating shaft. Then, one end of the wire is fixedly wound around the load pulley, and the other end of the wire is vertically engaged with the load cell. In this state, by moving the moving member in a direction away from the fixed member,
Rotational force is applied to the load pulley via the wire to rotate the rotating-side test piece holder, and the test piece held between the rotating-side test piece holding part and the fixed-side test piece holding part facing the same. A torsional force can be applied. At this time, the torque applied to the test piece can be obtained from the product of the detected value of the tensile load by the load cell with which the other end of the wire is engaged and the radius of the load pulley.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a state in which a torsion test apparatus 1 to which the present invention is applied is mounted on a general-purpose material testing machine 2. 2 is an enlarged view of a main part thereof, FIG. 3 is a sectional view taken along line AA of FIG. 2, and FIG. 4 is a sectional view taken along line BB of FIG.

In the material testing machine 2 in this example, two vertical screw rods 22 a and 22 b are rotatably supported on a table 21, and upper ends of the screw rods 22 a and 22 b are held by a cross yoke 23. In addition, both ends of the crosshead 24 are supported by nuts (not shown) on the screw rods 22a and 22b. The screw rods 22a and 22b are rotationally driven by a driving mechanism (not shown) arranged below the table 21.
The crosshead 24 is configured to move up and down by the rotation of 2a and 22b. In the material testing machine 2, a load cell 25 is attached to the cross yoke 23, and the load cell 25 is located on the testing machine center line CL.

In the torsion test apparatus 1 according to the present invention, all the components are mounted on a base plate 11, and the base plate 11 is positioned and fixed on the upper surface of a crosshead 24, and the tip of a wire 19 described later is connected to the load cell 25. It is used by vertically engaging the load sensitive part via the hook 251.

The support plate 1 is provided on the base plate 11.
2 is fixed, and on this support plate 12, a rotary gripper 13 and a fixed gripper 14 are arranged to face each other. The rotating grip 13 is fixed to one end surface of a horizontal rotating shaft 15, and the rotating shaft 15 is
2 and a pair of columns 16a, 16b fixed on
It is rotatably supported via 7a and 17b. The fixed gripper 14 is supported by one column 16 c fixed on the support plate 12.

A load pulley 18 is fixed to a portion of the rotating shaft 15 having one end face to which the rotary gripper 13 is fixed, supported by bearings 17a and 17b. Is fixed by a screw 191 and the wire 19 is connected to the load pulley 18.
It is wrapped around 3/4 lap. After this wire 19 is wound around the load pulley 18,
It extends vertically above the tester center line CL, and its tip is hooked on the hook 251 of the load cell 25 as described above.

Base plate 11 and support plate 1
2 each have a rectangular shape, and the base plate 11
Is fixed to the crosshead 24 of the material testing machine 2 so that its longitudinal direction is along, while the support plate 12 is fixed at one end side to the base plate 11 so that its longitudinal direction is along the direction perpendicular to it. The end side protrudes in an overhang shape to the front side of the material testing machine 2. Also,
A groove 121 having a uniform width is formed in the surface of the support plate 12 along the longitudinal direction, and two elongated holes 122 parallel to each other along the longitudinal direction are formed in a protruding portion from the material testing machine 2. Is formed. The column 16c that supports the fixed side gripper 14 is slidably disposed along the groove 121 with respect to the support plate 12,
A bolt penetrating the elongated hole 122 is fastened and fixed to the support plate 12 at an arbitrary position within the length of the elongated hole 12. By adjusting the position of the column 16c, the distance between the rotating grip 13 and the fixed grip 14 can be appropriately set according to the length of the test piece W.

The positioning and fixing of the base plate 11 with respect to the material testing machine 2 is performed by positioning a positioning pin 241 projecting above the center line CL of the testing machine on the upper surface of the crosshead 24 into a through hole 111 formed at the center of the base plate 11. Insert the base plate 11 so that it fits
It is performed by fastening with bolts while placed on top. The base plate 11 has two through holes 112 and 113 for positioning the support plate 12 on both sides in the longitudinal direction with the through hole 111 as a center.
2 and 113, respectively.
Are formed symmetrically with each other. On the other hand, the support plate 12 is provided with positioning pins 123 protruding from the back surface thereof.
This pin 123 is inserted into the through hole 112 of the base plate 11,
113, the bolt is fixed to the corresponding female screw group with bolts, so that the load plate 1
A tangent along one of the left and right vertical directions of a groove around which the wire 19 is formed around the wire 8 is located on the tester center line CL.

In order to use the torsion test apparatus 1 according to the embodiment of the present invention, the base plate 11 is fixed to the crosshead 24 of the material tester 2 as shown in FIGS. The wire 19 wound around 18 is extended vertically upward along the center line CL of the tester and hooked on the hook 25 of the load cell 25. Then, both ends of the test piece W are gripped by the rotating grip 13 and the fixed grip 14, respectively. When the material testing machine 2 is driven in this state to lower the crosshead 24 as shown by the arrow α in FIG. 2, the wire 19 is pulled relatively upward with respect to the load pulley 18, whereby The load pulley 18 rotates in the direction indicated by the arrow β in FIG. 2, and a torque T is applied to the test piece W. This torque T is the product of the detected value F of the tensile load acting on the load sensitive part of the load cell 25 via the wire 19 and the radius r of the load pulley 18,
That is, it can be obtained by T = Fr.

What is particularly notable in the above embodiment is that a torque is applied to the test piece W by the vertical movement of the crosshead 24 of the material testing machine 2 without requiring a dedicated drive source as a torsion test device. And a point that the output of the load cell 25 of the material testing machine 2 is used without requiring a dedicated torque cell for measuring the torque, thereby achieving simplification and compactness of the device configuration. .

The mounting position of the support plate 12 with respect to the base plate 11 is changed from one through hole 112 side to the other through hole 113 side as shown in FIG. By simply reversing, it is possible to perform a reverse rotation test.

In the above embodiment, an example is shown in which the torsion test device according to the present invention is mounted on a material testing machine in which the load cell 25 is mounted on the cross yoke 23, but the load cell 25 is mounted on the crosshead 24. The torsion test device according to the present invention can be attached to the attached material testing machine. In this case, the base plate 11 is fixed to the upper surface of the table 21 and the load pulley 18
Is extended vertically upward along the tester center line CL in the same manner as described above, and
Hooked on a load cell attached to the Then, by raising the cross head 24, the load pulley 18 rotates, and a rotational force can be applied to the rotary gripper 13.

[0021]

As described above, according to the present invention, the linear motion of the moving member such as the crosshead is rotated by the pulley and the wire by effectively utilizing the function of the general-purpose material testing machine. The torque is applied to the test piece holder by rotating the test piece holder, and the torque acting on the test piece by the rotation is obtained by the product of the load cell output of the material testing machine and the pulley radius. Thus, a torsional test apparatus having a simple and compact structure can be obtained without requiring a motor as a dedicated driving source or a dedicated torque cell unlike the conventional torsional test apparatus.

[Brief description of the drawings]

FIG. 1 is a front view showing a state in which a torsion test apparatus 1 to which the present invention is applied is mounted on a general-purpose material testing machine 2;

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a view as viewed in the direction of arrows AA in FIG. 2;

FIG. 4 is a sectional view taken along line BB of FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Torsion test apparatus 11 Base plate 12 Support plate 13 Rotation side gripper 14 Fixed side gripper 15 Rotation shaft 16a-16c Column 17a, 17b Bearing 18 Load pulley 19 Wire 2 Material testing machine 21 Table 22a, 22b Screw rod 23 Cross yoke 24 Crosshead 25 Load cell 251 Hook

Claims (1)

[Claims] A moving member that linearly moves toward and away from the fixed member, applies a load to the test piece by the linear movement of the moving member, and fixes the load applied to the test piece. A torsion test device used by being attached to a material testing machine configured to detect by a load cell provided on a member or a moving member, comprising: a base plate fixed to the fixed member or the moving member; A rotation shaft rotatably supported so as to be orthogonal to the direction of movement of the moving member, a rotation-side test piece holding portion fixed to the rotation shaft, and the base plate facing the rotation-side test piece holding portion. And a load pulley fixed to the rotating shaft. One end of the load pulley is connected to the load pulley. A wire is attached around the other end of the load cell and attached to the load sensing portion of the load cell. The wire and the load pulley convert the linear motion of the moving member into the rotary motion of the rotating test piece holder. A torsion test device characterized by being constituted.