JP3122929B2 - Contact type mark tracking device in tensile testing machine. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact mark tracking device for measuring the elongation of a test piece in an automatic tensile tester.

[0002]

2. Description of the Related Art In a conventional contact-type marking line tracking device, a point between two points corresponding to a marking line at a center parallel portion of a test piece is clamped by a tip of a clamping arm, and a contact pressure is applied to a surface of the test piece to thereby test the test piece. The degree of elongation of the central parallel portion was detected by the movement of the tip of the holding arm due to the frictional force between the tip of the holding arm and the test piece surface. Also, taking into account the standard test piece hardness and surface condition to provide detection conditions, the clamping pressure at the tip of the clamping arm is adjusted manually using a compression spring to optimize the friction pressure at the tip of the clamping arm. Had been given.

[0003]

As described above, in the conventional contact-type mark-tracking apparatus, a compression spring is used in order to determine the inter-mark-line elongation of the test piece, taking into account the standard hardness and surface condition of the test piece. Although the measurement was performed while adjusting the optimum, there are several hundred kinds of test pieces to be tested in the case of an automated tensile tester, and the elongation must be continuously and automatically detected. Among them, hard or soft,
In addition, the surface may be glossy or not, and in order to correspond to the hardness and surface condition of each test piece, it is not possible to apply an appropriate friction pressure by the above method, and it is difficult to apply a slip test such as an oil resistance test. In a test piece which is easy to use, there is a problem that the mark arm may slip during the test piece slipping and pulling, and may not be at a regular mark position.

[0004] In order to solve the above problems, the present invention continuously clamps test specimens with an optimal clamping force according to the hardness and surface condition of several hundred kinds of test specimens, and automatically and continuously and continuously. An object of the present invention is to enable the degree of elongation to be measured accurately.

[0005]

In order to achieve the above-mentioned object, a contact-type mark tracing device of the present invention detects the hardness and surface condition of a test specimen in advance, and externally detects the hardness and surface condition based on the information. By adjusting the clamping force of the driving unit that operates the clamping arm of the clamping unit by the electric signal or the manual knob, it is possible to clamp the test piece with the optimal force. The drive unit is an electric hand type driven by a motor or an air hand type driven by electric-air conversion. In addition, a spring is included inside the holding part, and during the tensile test, the holding part is inclined in the tensile direction around the support shaft according to the elongation of the test piece, and the change in the magnetic field of the permanent magnet provided at the rear end of the holding part When the magnetic sensor is activated, the motor rotates, the ball screw is driven and rotated accordingly, the support moves in the pulling direction, stops when the support is horizontal, and the encoder detects the amount of movement. It is characterized in that the degree of elongation of the piece can be measured.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described based on embodiments with reference to the drawings. FIG. 1 to FIG. 3 show a holding section 1 which is a main part of the contact-type marked line tracking device of the present invention, and a supporting section 2 which supports the holding section 1. The support portion 2 is supported so as to move by being screwed into a ball screw described later. The holding parts 1 are tip parts 1 projecting inward from each other.
a, 1a having a pair of holding arms 1A, 1A, a driving unit 13 for moving the pair of holding arms 1A, 1A toward and away from each other, and a rear end 1B for pivotally supporting the holding unit 1 to the support unit 2. You. A balancer 14 is provided at the rear end 1B of the holding section 1. The holding arm 1A of the holding portion 1,
1A is configured so that the tip portions 1a, 1a sandwich a marked portion in the thickness direction of the central parallel portion of the test piece (not shown in this figure). The holding portion 1 is supported by the supporting portion 2 by a support shaft 3, and when the test piece is pulled, the tip 1 a of the holding portion moves in the pulling direction (in the embodiment, upward), and the rear end of the holding portion. 1B moves in the direction opposite to the pulling direction (clockwise CW direction in the embodiment). A permanent magnet 4 is provided at the rear end portion 1B of the holding portion. Provided behind. The magnetic sensor 5 converts a change in the direction of the magnetic field of the permanent magnet 4 into an electric signal, and outputs the converted electric signal to a computer (not shown). The motor 10 for tracking and moving the support unit 2 is rotated by the electric signal sent from the computer, is transmitted to the ball screw 6, and moves in the pulling direction until the holding unit 1 is horizontal.
In order to prevent the holding portion 1 from moving from the horizontal state in the counterclockwise CCW direction, a stopper 7 is provided on the support portion 2 to prevent the rear end portion 1B of the holding portion from moving when the holding portion 1 becomes horizontal. It is. The drive unit 13 uses an electric hand type driven by a motor or an air hand type driven by electric / air conversion.

FIG. 4 is a graph showing an electric signal output from the magnetic sensor when the holding portion 1 is inclined in the clockwise direction CW and the counterclockwise direction CCW. When the stopper 7 is not provided, the holding portion 1 can be tilted up to 60 ° in the counterclockwise CCW direction and the clockwise CW direction at the maximum, and when the holding portion 1 tilts in the counterclockwise CCW direction, the magnetic sensor 5 outputs a positive electric signal. Conversely, when the magnetic sensor 5 tilts in the clockwise direction CW, the magnetic sensor 5 outputs a negative electric signal.

FIG. 5 shows an embodiment of a marker tracking device. After detecting the hardness and surface condition of the test piece 9 in advance, the wide portion 9A of the test piece is chucked by the test piece chucks 8a and 8b,
Hold the test piece 9 in the vertical direction. The holding arms 1A, 1A of the holding portion 1 held in the horizontal direction hold the two marked portions in the thickness direction of the central parallel portion 9B of the chucked test piece and perform a tensile test. At this time, the lower test piece chuck 8a is fixed, and the upper test piece chuck 8b is pulled in the upward direction of the arrow. When the test piece 9 is extended, the upper and lower holding portions 1 and 1 move in the clockwise CW direction about the respective support shafts 3 and 3. At this time, a negative electric signal is output from the magnetic sensors 5 and 5 to the computer by the change of the magnetic field by the permanent magnets 4 and 4 provided at the rear end of the holding parts 1 and 1, respectively. A computer (not shown) to which the data is sent operates the motors 10, 10 in an attempt to reduce the electric signal to zero. Ball screws 6 driven by the motors 10
6 rotates and moves the support parts 2 and 2 in the direction of the arrow. At this time, when the support parts 2, 2 are in a horizontal state, the rear ends 1B, 1B of the holding parts do not move in the direction of the arrow by the stoppers 7, 7, so that the support parts 2, 2 stop. Encoders 11, 11 provided at the upper ends of the ball screws 6, 6 detect the amount of movement of the support portions 2, 2. Therefore, the elongation of the test piece is measured.

FIG. 6 shows an example in which a compression spring 12 is included inside the holding arm 1A.

[0010]

According to the contact marking system in the automatic tensile tester of the present invention, since the hardness and surface condition of the test piece are detected in advance, different types of test pieces can be continuously and individually tested. The tensile test can be accurately performed according to the characteristics of the above. In addition, by making the holding part an electric hand type driven by a motor or an air hand type by electric-air conversion, the holding force can be automatically adjusted based on the detection data.
It is possible to clamp the test piece with the optimal force, and by including a compression spring inside the clamping arm, the interaction with the electric hand (air hand) enables more soft touch and very weak force It is possible to hold the test piece with an optimum force with a suitable holding force. In addition, when the test piece is pulled, only the holding portion is inclined, and then the support portion is moved by an electric signal, and stops when the holding portion is in a horizontal state, thereby accurately elongating the test piece. It has the effect of being able to measure. In addition, when a tensile test is performed on a test piece held by the holding arm between two marked line positions in the parallel portion of the test piece, the test piece is elongated, the holding arm is tilted, and the tilt is detected by a magnetic sensor. Then, the clamping arm is moved by the servo mechanism in a direction to eliminate the inclination of the clamping arm. In this case, at the start of the operation, the arm is balanced around the fulcrum due to the inertia of the arm.

[Brief description of the drawings]

FIG. 1 is a plan view of a holding unit and a support unit of a contact-type marked line tracking device.

FIG. 2 is a side view of a holding portion and a support portion of the contact-type marking line tracking device.

FIG. 3 is a side view of the contact-type marking line tracking device in which a holding portion is inclined in a clockwise direction CW.

FIG. 4 is a graph showing an electric signal output from the magnetic sensor when the holding portion is inclined.

FIG. 5 is a side view of the entire contact marker tracking device.

FIG. 6 is a plan view showing a holding arm provided with a compression spring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Holding part 1A Holding arm 1a Tip part 2 Support part 3 Support shaft 4 Permanent magnet 5 Magnetic sensor 6 Ball screw 7 Stopper 8 Test piece chuck 9 Test piece 10 Motor 11 Encoder 12 Compression spring 13 Drive part 14 Balancer

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Claims (6)

(57) [Claims] 1. The hardness and surface condition of a test piece are detected in advance, and based on the information, the holding force of a driving unit that operates a holding arm of a holding unit is adjusted, and the test piece is held with an optimum force. The tensile test allows for the elongation of the specimen during the tensile test.
When the holding part tilts in the tension direction about the support shaft,
As the magnetic field of the permanent magnet provided at the rear end of the
When the sensor operates, the motor rotates,
The ball screw drives and rotates, and the support moves in the pulling direction.
The holding part is in a horizontal state and moved by the encoder.
The amount is detected and the elongation of the test piece can be measured.
Sea- shaped contact mark tracking device. 2. The contact-type marked line tracking device according to claim 1, wherein the drive unit is an electric hand type driven by a motor. 3. The contact-type marked line tracking device according to claim 1, wherein the driving unit is an air hand type. 4. The contact-type mark tracking device according to claim 2, wherein a compression spring is provided between the pair of holding arms to control the holding force by an interaction between the electric hand force and the spring force. 5. The contact-type marking line tracking device according to claim 3, wherein a compression spring is provided between the pair of holding arms to control the holding force by an interaction between an air hand force and a spring force. 6. Any of the contact type marked line tracking system according to claim 1 to 5 wherein is provided a balancer to the clamping portion.