JPH08261901A - Marked line detecting mechanism in tension test - Google Patents

Abstract

PURPOSE: To minimize the air flow and precisely detect the displacement of a marked line marked on a test piece by providing a balance weight conforming to a clip arm on the outside of a constant temperature oven in such a manner as to be capable of rising and falling, and stably supporting upper and lower clip arms in such a manner as to be capable of rising and lowering and well- balanced. CONSTITUTION: A pair of upper and lower clip arms 1, 2 for nipping a test piece AS are provided in a constant temperature oven R. In a frame body 3 arranged on the outside of the constant temperature oven R, thick plate-like front and rear balance weights 17 are hooked on vertically raised front guide bar 8 and rear guide bar in such a manner as to be capable of rising and failing. The upper and lower arms 1, 2 are well-balanced with the weights 17, and stably supported in such a manner as to be capable of rising and lowering and well-balanced. Further, the upper and lower arms 1, 2 are supported by two parallel spaced wire rods 19, 20 in two spaced positions of their base end parts 1A and 2A. Thus, time danger of both lateral end parts being alternately vertically oscillated is never caused in the upper and lower arms 1, 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tensile test for detecting displacement of a marked line on a test piece when a tensile test is performed on a material having a large elongation such as plastic or rubber in a thermostatic chamber. Regarding the line detection mechanism.

[0002]

2. Description of the Related Art Conventionally, in a tensile test of a flexible material such as plastic or rubber, a marked line on a test piece is deformed when it is pulled. A means for accurately detecting the position of the line has been required. Therefore, for example, an optical non-contact gage mark detecting device has been proposed in Japanese Utility Model Publication No. 4-21090, and an electrical contact type inter-marker displacement measuring device has been proposed in Japanese Utility Model Publication No. 6-18269.

In addition to the above, a contact type mark detecting device shown in FIG. 6 has been known. In this conventional device, a vertical guide rod 34 is inserted between an upper clip portion 32 and a lower clip portion 33 that sandwich a test piece 31, and the upper clip portion 32 is a balancer via a wire 36. The wire 36 is connected to the pulley 35, and is hooked on the pulleys 38, 38 provided on the top plate 45 of the mark detecting device. As a result, the upper clip portion 32 and the balancer 35 are vertically supported by the pulleys 38, 38 so as to be vertically movable. Similarly, the lower clip portion 33 and the balancer 37 are supported by pulleys 39, 39 and one wire 44 so as to be vertically movable.

Both ends of the test piece 31 are held by the grip portions 41, 41 of the tensile tester.
Reference numerals 1 and 41 are connected to the upper and lower crossheads of the tensile tester. Therefore, the tip of the upper clip portion 32 clamps the upper side of the test piece 31. Similarly, the tip of the lower clip portion 33 holds the lower side of the test piece 31. Reference numeral 40 in the figure indicates a constant temperature bath. Here, the corresponding portion of the vertical guide rod 34, the upper clip portion 32, the lower clip portion 33, and the test piece 31 are arranged in a constant temperature bath 40.

During the tensile test, the protrusions 41, 41 are
Since the test piece 31 moves in the extending direction, the test piece 31 extends and the position of the marked line is displaced. This amount of displacement is the pulley 3
The rotation detector 42 directly connected to the No. 8 and the rotation detector 43 directly connected to the pulley 39 are the devices.

[0006]

Conventionally, in an optical non-contact type mark tracking device, when performing a tensile test at a low temperature and when replacing the test piece, the marking line marked on the test piece by opening and closing the test tank door is used. However, there is a problem that frost adheres to the viewing window for detecting the distance, which hinders the system for optically detecting the displacement of the marked line. Further, this device has a problem that the mark detection mechanism and the measurement control system are more expensive than those of the contact type mark tracking device of the electric signal type.

Further, in the contact type gaze tracking device, since the detection mechanism is constructed to penetrate from the inside of the constant temperature bath to the outside of the constant temperature bath, the amount of heat inflow and outflow through the detection mechanism increases, so that the temperature of the constant temperature bath is adjusted. There is a problem that it affects the temperature control system (heater capacity, refrigerator capacity). In addition, in order to not interfere with the operation of this detection mechanism, there is a problem that a cutout is provided in the constant temperature bath and modification is required to minimize the heat inflow and outflow from this cutout. It was In this contact type, the detection mechanism and the measurement control system can be economically constructed as compared with the non-contact type mark tracking device, but the cost required for the constant temperature bath is generated, so that it is not always economical as a whole. There was a problem that it could not be configured.

The contact type mark detecting device shown in FIG. 6 has a great advantage that it can be economically constructed because of its simple structure. However, since a considerable portion of the vertical guide rod and the pair of upper and lower clip parts through which the vertical guide rod is inserted are integrally arranged in the thermostatic chamber, thermal deformation of the vertical guide rod may occur during high temperature testing. In addition, during the test at low temperature, there is a problem that the displacement of the marked line cannot be accurately detected because the vertical movement of the clip portion is obstructed by the frost attached to the vertical guide rod.

In order to solve the above problems, the present invention provides
Minimize the remodeling of the temperature chamber, minimize the air flow between the inside and outside of the temperature chamber, and economically use the mark detection mechanism in the tensile test to accurately detect the displacement of the mark marked on the test piece. It is intended to be provided to.

[0010]

In order to solve the above-mentioned problems, the marking line detecting mechanism in the tensile test of the present invention is provided with an upper clip arm and a lower clip arm for holding a test piece in a constant temperature bath, A balance weight corresponding to each of the clip arms is provided up and down outside the constant temperature bath, and the upper clip arm and the corresponding balance weight are connected by parallel wire rods spaced apart from each other, with a rotating portion interposed. This upper clip arm can be lifted vertically and stably and stably, and similarly, the lower clip arm and the corresponding balance weight are connected by parallel wire rods with a space between them, and another rotating portion is interposed, and the lower clip arm is connected. It is characterized in that the arm can be raised and lowered and balanced and stably supported.

Another rotating portion is provided at a position opposite to the rotating portion with a pair of guide pulleys, and the other rotating portion is interposed between the upper clip arm and the balance weight so that a wire rod is formed. The wire is stretched in parallel with an interval, and another rotating part is also interposed between the lower clip arm and the balance weight, and the wire is stretched in parallel with an interval to provide the clip arm and the balance weight. Is connected in a loop shape.

[0012]

According to the marking line detecting mechanism in the tensile test of the present invention, the pair of upper and lower clip arms for sandwiching the test piece can be raised and lowered and are stably balanced and balanced, so that the pair of upper and lower clip arms can be accurately tested. It moves up and down following the displacement of the marked line on one side.

[0013]

EXAMPLE FIG. 1 shows the marking line detection mechanism in the tensile test of the present invention.
It will be described with reference to FIGS. First, a pair of upper clip arm 1 and lower clip arm 2 for sandwiching the test piece S are provided in the constant temperature bath R. On the other hand, in the frame body 3 arranged outside the constant temperature bath R, a vertically-standing front guide rod 8 is provided with a square thick plate-shaped front balance weight 17 so as to be vertically movable, and a rear guide rod 9 is also provided with a rectangular thick plate. A rear balance weight 18 in the shape of a strip is provided so as to be able to move up and down.

The frame 3 is composed of a horizontal rectangular upper plate 6 and a lower plate 7, and vertical columns 4, 4 and 5, 5 fixed to the four corners of the upper plate 6 and the lower plate 7, respectively. It is shaped like a rather tall rectangle. The front guide rod 8 is vertically erected slightly above the center between the columns 4 and 4 forming the front frame of the frame body, and is provided across the upper plate 6 and the lower plate 7. There is. Similarly, columns 5 and 5 that form the rear frame
A rear guide bar 9 is provided vertically upright from a position substantially inward from the center of the space. Front balance weight 17
Has a guide hole that passes vertically through its center,
The front guide bar 8 is loosely inserted in this guide hole. Similarly, the rear guide rod 9 is loosely inserted into the guide hole formed in the rear balance weight 18. A front rotating part 10 and a rear rotating part 11, which will be described later, are provided on the upper plate 6 as a pair.

Both the upper clip arm 1 and the lower clip arm 2 are formed in the shape of a long rectangular parallelepiped. The upper clip arm 1 has a slightly long base end portion 1A.
And a slightly shorter tip portion 1B are integrally formed, and similarly, the lower clip arm 2 is formed by integrating the base end portion 2A and the tip portion 2B. The tip portion 1B clamps the upper side of the test piece S positioned vertically in the figure, and the tip portion 2B
Holds the lower side of the test piece S. The upper clip arm 1 and the lower clip arm 2 have base end portions 1A and 2A, respectively.
Is supported by.

The tips of the two parallel wire rods 19 are separately fixed to two locations on the upper surface of the base end portion 1A of the upper clip arm 1 spaced apart along the longitudinal direction. The other ends of the two wire rods 19 are separately fixed to the upper surface of the front balance weight 17 at two locations spaced apart along the longitudinal direction of the guide hole. Thus, the upper clip arm 1 and the front balance weight 17 are connected to each other by the two parallel wire rods 19 with the front pivoting portion 10 interposed therebetween. It should be noted that the base end portion 1A has pores 2 into which another wire 20 is loosely inserted.
1 is formed in two places with a space.

The tip ends of the two wire rods 20 are separately fixed to two locations on the upper surface of the base end portion 2A of the lower clip arm 2 spaced apart along the longitudinal direction. The other end of the wire 20 is separately fixed to the upper surface of the rear balance weight 18 at two locations spaced apart along the longitudinal direction of the guide hole. This allows the lower clip arm 2
The rear balance weight 18 and the rear balance weight 18 are connected to each other by the two parallel wire rods 20 spaced apart from each other with the rear rotating portion 11 interposed. At this time, the wire 20 passes through the pores 21, 21. In addition, this wire 19
The wire 20 is a thin wire.

With the above structure, the upper clip arm 1
The lower clip arm 2 and the lower clip arm 2 are horizontally suspended in the constant temperature bath R. Therefore, the upper clip arm 1 is balanced with the front balance weight 17 so as to be lifted and lowered and balanced and stably supported. Similarly, the lower clip arm 2 is balanced with the rear balance weight 18 so as to be lifted and lowered and balanced and stably supported. Further, the upper clip arm 1 is supported by two parallel wire rods 19 which are spaced apart from each other at the base end portion 1A thereof. It is supported by two wire rods 20 spaced in parallel at two points spaced apart by 2A. With this configuration, there is no danger that the left and right ends of the upper clip arm 1 and the lower clip arm 2 alternately swing (pitch) in the vertical direction. Therefore, during the tensile test of the test piece S, there is no possibility that an external force that hinders the detection of the displacement of the marked lines on the upper side and the lower side of the test piece S is applied to the test piece S.

The structure and operation of the front rotating part 10 and the rear rotating part 11 provided on the upper surface of the upper plate 6 will be described below. The front turning portion 10 is formed by an outer front guide pulley 12 and a front guide pulley 12 that are in contact with the arrow L in FIG.
The outer front guide pulley 12 is provided with a rotation detector 22 for detecting the displacement of the upper marked line of the test piece S. Similarly, the rear surface rotating portion 11 is provided with an outer rear surface guide pulley 13
And the inner rear guide pulley 13, the outer rear guide pulley 13 is also provided with a rotation detector 22 for detecting the displacement of the lower marked line.

The front rotating portion 10 and the rear rotating portion 11 are provided in such a manner that the inner front guide pulley 12 and the inner rear guide pulley 13 are opposed to each other, and the positions thereof are staggered and slightly displaced from each other. . This front guide pulley 12, 1
2 and the rear surface guide pulleys 13 and 13 are provided with a pair of pulleys at both ends of a rotatable rotary shaft with a space therebetween. V-shaped grooves are formed on the outer peripheral edges of these pulleys, and the bottoms of these grooves form a circumferential strip 23 around the pulleys. The wire rod 19 and the wire rod 20 are hung on each of the circumferential strips 23.

The above-mentioned arrow line L is a center line which is on the same plane as the plane including the axis of the above-mentioned rotating shaft and which is parallel to these axes. From the intersection of this arrow line L and the circumferential strip 23 of the pair of pulleys of the front guide pulley 12 on the inside, wire rods 19 and 19 hang vertically downward in the figure, and an insertion hole formed in the upper end wall of the constant temperature bath R. After 26, the upper clip arm 1 in the thermostat R is lifted up and down, balanced, and stably supported. From the intersection of this arrow line L and the circumferential line 23 of the pair of pulleys of the inner rear guide pulley 13, the wire rods 20, 20
Hangs vertically downward in the figure, passes through the insertion hole 26, and then the thermostat R
The lower clip arm 2 in the inside can be lifted up and down and balanced and supported stably.

The outer line 24 in the figure is parallel to the arrow line L and intersects with the circumferential line 23 of the pair of pulleys of the outer front guide pulley 12, and the center point 25 of this outer line 24.
Is located on an extension of the central axis of the front guide rod 8.
The wire rods 19, 19 hanging down from the intersection of the outer wire 24 and the circumferential strip 23 pass through the small holes formed in the top plate 6,
Outside the constant temperature tank R, a front balance weight 17 provided on the front guide rod 8 so as to be able to move up and down is supported. Similarly, the wire rods 20, 20 hanging from the circumferential strips 23 of the pair of pulleys of the outer rear guide pulley 13 pass through the small holes of the upper surface plate 6 and can be raised and lowered to the rear guide rod 9 outside the constant temperature bath R. The rear balance weight 18 prepared for the above is supported.

In the figure, in the constant temperature bath R, in addition to the upper clip arm 1 and the lower clip arm 2, a test piece S and a grip portion 14 for holding the upper end of the test piece S and the lower end thereof are held. The grip portion 15 and the support rods 16 and 16 are arranged. The grip portion 14 and the grip portion 15 are the support rod 1
It is connected via 6 and 16 to the upper and lower crossheads of the tensile tester. Since the support rods 16 and 16 move up and down during the tensile test, insertion holes therefor are formed in the upper end wall and the lower end wall of the constant temperature bath R. Since the flow path between the constant temperature bath R and the outside air is limited to the insertion holes of the wire rods 19 and 20 and the insertion holes of the support rods, the temperature inside the constant temperature bath R is accurately maintained. Furthermore, even in tensile tests at high and low temperatures,
Since there are no disturbance factors such as frosting and deformation that hinder the lifting and lowering of the upper clip arm 1 and the lower clip arm 2, it is possible to accurately detect the displacement of the marked line in a stable state in a wide temperature range.

The rotation detector of the rotating portion can be easily connected to a measurement control system to control the tensile test and to analyze the displacement of the marked line on the test piece. . This measurement control system may be provided, for example, in the marking line detection mechanism of the present invention, or may be incorporated in the control system of the tensile tester.

4 and 5 show another embodiment. Frame 3
The front guide pulleys 27, 27 on the lower surface of the lower plate 7 of
It is provided at a position opposite to the front guide pulleys 12, 12 provided on the upper surface of the upper surface plate 6. Similarly, the rear surface guide pulleys 28, 28 are provided on the lower surface of the lower surface plate 7 at positions opposite to the rear surface guide pulleys 13, 13 provided on the upper surface of the upper surface plate 6. With the above configuration, the upper clip arm 1 and the front balance weight 17 are connected in a loop by the wire 19 with the front guide pulleys 27, 27 and the front guide pulleys 12, 12 interposed therebetween. . Similarly, the lower clip arm 2 and the rear balance weight 18 are provided with the rear guide pulleys 28 and 28 and the rear guide pulleys 13 and 13 to interpose the wire rod 2
0s are connected in a loop.

That is, two wire rods 19 which are spaced apart in parallel are provided.
Of the upper clip arm 1 is fixed to two places on the upper surface of the base end portion 1A of the upper clip arm 1 with a space therebetween, and the wire 19 is passed through the through hole 26 and the front guide pulleys 12 and 12, and the other end is made to face the front side. 2 on the upper surface of the balance weight 17
It is stuck in place. On the other hand, the ends of the other two parallel wire rods 19 are fixed to two spaced apart lower surfaces of the front balance weight 17, and the wire rods 19 are passed through the front guide pulleys 27, 27, and the constant temperature bath R. The two parallel wires 19 are spaced apart by passing through the insertion hole 30 formed in the lower end wall, rising vertically, and fixing the other tip to two spaced apart lower surfaces of the base end 1A. It is laid open. At this time, the wire 19 has pores 29, 29 formed at intervals in the base end portion 2A of the lower clip arm 2.
Is passing through. The lower clip arm 2 and the rear balance weight 18 are connected in a loop by the wire 20 in the same manner as described above.

[0027]

The marking line detecting mechanism in the tensile test of the present invention is provided with a pair of upper clip arm and lower clip arm for sandwiching the test piece inside the constant temperature bath, and corresponds to each of the clip arms outside the constant temperature bath. A balance weight is provided so that it can be raised and lowered, and the upper clip arm and the corresponding balance weight are connected by parallel wire rods that are spaced apart from each other. Similarly, the lower clip arm and the corresponding balance weight are connected by parallel wire rods with a space between them, and another pivoting part is interposed so that the lower clip arm can be raised and lowered and stably balanced and balanced. Therefore, the pair of upper and lower clip arms are
Since there is no danger of pitching, it has the effect of accurately detecting the displacement of the marked line on the test piece. The pair of upper and lower clip arms can be lifted up and down in a suspended state and stably and stably balanced, so that the clip arms can follow the displacement of the marked line with almost no resistance.

Since the pair of upper and lower clip arms are arranged in the constant temperature oven, the air flow passage between the constant temperature oven and the outside air is limited, so that the temperature in the constant temperature oven can be maintained accurately. At low temperatures, there is no frost that prevents the pair of upper and lower clip arms from moving up and down, and even at high temperatures,
Since a pair of upper and lower clip arms can be raised and lowered and can be stably and stably balanced, it has an effect of accurately detecting the displacement of the marked line in a stable state in a wide temperature range. Further, when the existing constant temperature bath is used, the constant temperature bath can be easily and economically modified.

Another rotating portion is provided at a position opposite to the rotating portion by pairing the guide pulleys, and another rotating portion is interposed between the upper clip arm and the balance weight so that the wire is parallel. The clip arm and the balance weight are stretched in parallel with each other by interposing another rotating part between the lower clip arm and the balance weight. Since they are connected in a loop, the pair of upper and lower clip arms can be more stably supported.

[Brief description of drawings]

FIG. 1 is a front view showing a marking line detection mechanism in a tensile test of the present invention.

FIG. 2 is a side view showing the marking line detection mechanism.

FIG. 3 is a plan view showing the marking line detection mechanism.

FIG. 4 is a front view showing another embodiment.

FIG. 5 is a side view of the same.

FIG. 6 is an explanatory view showing a conventional contact-type mark detection device.

[Explanation of symbols]

 1 Upper Clip Arm 2 Lower Clip Arm 3 Frame 4 Strut 5 Strut 8 Front Guide Rod 9 Rear Guide Rod 10 Front Rotating Part 11 Rear Rotating Part 17 Front Balance Weight 18 Rear Balance Weight 19 Wire Rod 20 Wire Rod S Constant Temperature Tank

Claims (2)

[Claims] 1. A pair of an upper clip arm and a lower clip arm for sandwiching a test piece are provided inside a thermostat, and balance weights corresponding to the respective clip arms are provided outside the thermostat so that the balance weight can be raised and lowered. The arms and the corresponding balance weights are connected by parallel wire rods with a space between them, and the upper clip arm can be lifted up and down and stably balanced in a stable manner by interposing a rotating portion, and it also corresponds to the lower clip arm. The balance weight is connected by parallel wire rods with an interval, and another pivoting portion is interposed, so that the lower clip arm can be raised and lowered and stably balanced and balanced. Line detection mechanism. 2. A wire rod having a pair of guide pulleys at a position opposite to the rotating portion to provide another rotating portion, and another rotating portion interposed between the upper clip arm and the balance weight. Are extended in parallel at intervals, and another rotating part is similarly interposed between the lower clip arm and the balance weight to extend the wire rod in parallel at an interval to extend the clip arm and the balance weight. The marked line detecting mechanism in the tensile test according to claim 1, wherein and are connected in a loop.