KR20220073120A - Fixing gripper for tensile strength testing machine and tensile strength testing machine having the gripper - Google Patents

Abstract

The present invention relates to a fixed gripper for a tensile strength measuring instrument, wherein the first and second legs are arranged in the form of tongs with front ends close to each other and rear ends open to each other, and the first and second legs adjacent to the front end are opposed to each other The first leg and the second leg are respectively coupled to opposite sides of the first leg and the second leg at the rear of the hinge shaft and are respectively coupled to the sides of the hinge shaft for hinge-connecting the first and second legs. a gripper unit including an elastic member for connecting them; a first rod positioned between the first leg and the second leg at the rear of the elastic member and having one end connected to a tensile strength measuring device to move up and down to measure the tensile strength; a second rod having one end hinged to the rear end of the first leg by a first hinge and extending toward the first rod; and a third rod having one end hinged to the rear end of the second leg by a second hinge and extending toward the first rod; Including, the other ends of the first rod, the second rod and the third rod are hinged together by a third hinge having a single hinge shaft, so that the first rod is vertically moved between the first and second legs. As it moves, the second rod and the third rod, and the first leg and the second leg are interlocked.
The present invention also relates to a tensile strength measuring device comprising the fixed gripper.

Description

FIXING GRIPPER FOR TENSILE STRENGTH TESTING MACHINE AND TENSILE STRENGTH TESTING MACHINE HAVING THE GRIPPER

The present invention relates to a fixed gripper for a tensile strength measuring instrument, and more particularly, to a fixed gripper for a tensile strength measuring instrument that can firmly hold and grip the specimen without slipping even when a tensile force is applied to the specimen fixed to the gripper. it's about

The present invention also relates to a tensile strength measuring device provided with said fixed gripper.

When designing a product, the physical and mechanical properties of a material are measured through a tensile test using a specimen manufactured to a predetermined standard in order to measure the physical and mechanical properties of the material, particularly strength or elongation.

The tensile test of such a material is to measure the yield point, proof stress, tensile strength, yield elongation, elongation at break, and cross-sectional shrinkage of the material by gradually pulling the specimen. are doing

In addition, in the case of a battery such as a secondary battery, a larger capacity battery is realized by connecting several batteries. In order to connect the battery, the battery is welded, ultrasonically fused, or bonded to a metal plate, and a tensile strength meter is also used to measure the welding strength or adhesion strength of the metal plate.

1 shows a fixed gripper 1 used in a conventional tensile strength measuring instrument.

As shown, the conventional fixed gripper 1 grips the specimen between two legs 2 and 3 forming the tongs, and pulls the specimen with a moving device connected to the fixed gripper 1 to measure the tensile strength. do. The gripper 1 is provided with a mechanism for approaching and separating the legs in order to firmly fix the specimen between the legs. That is, a bolt or a threaded part 4 having a screw is fastened to a threaded hole (not shown) formed in the first leg 2 , and the threaded part 4 is rotated with respect to the first leg 2 to rotate the first By bringing the leg 2 closer to the second leg 3 , the specimen held at the ends of the first and second legs 1 and 2 is firmly fixed. When the screw part 4 is rotated in the opposite direction, the first leg 2 moves away from the second leg 3 , so that the specimen can be removed from the ends of the first and second legs 2 and 3 .

The screw portion 4 has a screw head portion 4a on its upper part, and a lever 5 as shown in the screw head portion 4a is fastened and the specimen is fixed by tightening the lever 5 by turning the screw head portion 4a. . Alternatively, there is a method of fixing the specimen by making the screw head 4a in the shape of a hexagonal bolt and tightening it with a hexagonal wrench.

However, since the above-described conventional fixed gripper 1 tightens the lever 5 or the hexagon wrench with human force, there is a limitation in securely tightening the specimen, and there is a problem in that the fatigue of the operator is increased when measuring the tensile strength.

In addition, if the specimen is not securely tightened, the specimen may come out when the tensile strength is measured by pulling the gripper at a constant speed. In particular, in the case of a specimen made of a slippery material, this risk further increases.

Therefore, it would be desirable to develop a technology capable of securely holding and fixing the specimen while firmly maintaining the specimen even when a tensile force is applied.

Japanese Patent Laid-Open No. 2000-321007

The present invention has been made to solve the above problems, and it is an object of the present invention to provide a fixed gripper for a tensile strength measuring instrument that can grip the specimen simply and reliably by applying an upward force to lift the specimen. .

Another object of the present invention is to provide a fixed gripper capable of continuously and reliably holding a specimen even when a tensile force is applied after gripping the specimen.

Another object of the present invention is to provide a tensile strength measuring device having the above-described fixed gripper.

In order to solve the above problems, the fixed gripper for a tensile strength measuring device of the present invention includes the first and second legs arranged in the form of tongs with front ends close to each other and rear ends open to each other, and the first leg adjacent to the front end and a hinge shaft respectively coupled to opposite sides of the second leg to hinge-couple the first leg and the second leg; a gripper unit including an elastic member connecting the leg and the second leg; a first rod positioned between the first leg and the second leg at the rear of the elastic member and having one end connected to a tensile strength measuring device to move up and down to measure the tensile strength; a second rod having one end hinged to the rear end of the first leg by a first hinge and extending toward the first rod; and a third rod having one end hinged to the rear end of the second leg by a second hinge and extending toward the first rod; Including, the other ends of the first rod, the second rod and the third rod are hinged together by a third hinge having a single hinge shaft, so that the first rod is vertically moved between the first and second legs. As it moves, the second rod and the third rod, the first leg and the second leg are characterized in that the interlocking movement.

As an example, the elastic member may be one of a coil spring, a rubber block, and a snap ring.

As an example, one end of the first rod is installed in a tensile strength measuring device and may be coupled to a load cell that moves up and down by a driving unit.

Specifically, the load cell may be coupled to a moving member that is slidably coupled to the tensile strength measuring device.

As an example, in the first rod, the other end of the first rod coupled to the third hinge moves from a position below the rear end of the first leg and the second leg to a position parallel to the rear end. It can have movement strokes.

Alternatively, the first rod may have a vertical movement stroke in which the other end of the first rod coupled to the third hinge moves from a position adjacent to the elastic member to a position parallel to the rear end.

Specifically, when the first rod is positioned at a position adjacent to the elastic member, the first leg and the second leg are adjacent to each other so that the elastic member therebetween is contracted.

In addition, when the first rod is positioned parallel to the rear end of the first leg and the second leg, the first leg and the second leg are spread so that the elastic member therebetween expands.

Preferably, a protrusion for holding the specimen is formed on the specimen contact surface of the tip portions of the first leg and the second leg for holding the specimen.

As another embodiment, the first rod may include an upper rod and a lower rod, and the upper rod and the lower rod may be hinged by a fourth hinge.

As another embodiment, a support member coupled to the first rod in a direction transverse to the first rod and having both ends slidably coupled to a rail part built in the tensile strength measuring device is provided, and the slide of the support member is provided. The vertical movement of the first rod may be guided by the movement.

In another aspect, the present invention is characterized in that the tensile strength measuring instrument having a fixed gripper for the tensile strength measuring instrument.

Since the fixed gripper for a tensile strength measuring instrument of the present invention has a structure for fixing the specimen by pulling upward, it is possible to grip the specimen simply and reliably.

In addition, since the structure is more tightened as it is pulled upward by the tensile force, there is little possibility that the gripper will be loosened during the tensile process, so that the specimen can be continuously and reliably maintained, thereby minimizing measurement error.

1 shows a fixed gripper used in a conventional tensile strength measuring device.
2 is a perspective view showing the tensile strength measuring device and the fixed gripper for the tensile strength measuring device according to the first embodiment of the present invention before operation.
3 is a schematic view showing the direction of force during operation of the fixed gripper for a tensile strength measuring device of the present invention.
4 is a schematic diagram showing in more detail the direction of force during the operation before and after operation of the fixed gripper for a tensile strength measuring instrument of the present invention.
FIG. 5 is a perspective view illustrating a state after an operation in which a tensile force is applied to the fixed gripper of FIG. 2 .
6 is a front view of the state after operation of FIG. 5 .
7 is a schematic diagram illustrating an example of a shape for gripping a specimen with a gripper part, which is a component of the present invention.
8 is a perspective view showing the tensile strength measuring device and the fixed gripper for the tensile strength measuring device according to another embodiment of the present invention before operation.
9 is a perspective view showing the tensile strength measuring device and the fixed gripper for the tensile strength measuring device according to another embodiment of the present invention after operation.
10 is a front view showing the tensile strength measuring device of FIG. 9 and the fixed gripper for the tensile strength measuring device after operation.

Hereinafter, the detailed configuration of the present invention will be described in detail with reference to the accompanying drawings and various embodiments. The embodiments described below are illustratively shown to help the understanding of the present invention, and the accompanying drawings are not drawn to scale to help the understanding of the present invention, and dimensions of some components may be exaggerated. .

Since the present invention can have various changes and can have various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

The fixed gripper for a tensile strength measuring instrument of the present invention is characterized in that it has a structure in which the specimen is tightened as it is pulled from above. To this end, the present invention is provided with three rods and three hinges on the upper portion of the gripper in the shape of tongs for gripping the specimen. In particular, one hinge has a structure in which the ends of three rods are all hinged to one hinge shaft, and when the central rod among the rods is pulled upward, the specimen is tightened at the lower end of the tongs-shaped gripper part. .

According to the structure of the present invention, as the tensile force pulling from the upper part is applied, the specimen is tightened and fixed more tightly by the gripper unit, so that the specimen is stably fixed to the gripper without falling out even during the tensile test, thereby reducing the error during the tensile test. can

Hereinafter, each embodiment of the present invention will be described in detail with reference to the drawings.

(First embodiment)

A first embodiment of the present invention will be described with reference to Figs.

2 is a perspective view showing the state before operation of the tensile strength measuring device 200 and the fixed gripper 100 for the tensile strength measuring device of the present invention, and FIG. 3 is the direction of the force during operation of the fixed gripper for the tensile strength measuring device of the present invention. It is a schematic diagram shown.

2 and 3 , the fixed gripper 100 of the present embodiment includes a first leg 111 and a second leg 112 that form tongs, and the first leg 111 and a gripper part 110 for which the tip of the second leg 112 grips the specimen; a first rod 120 positioned between the first leg 111 and the second leg 112 and having one end connected to the tensile strength measuring device 200 to move up and down to measure the tensile strength; a second rod 130 having one end hinged to the rear end of the first leg 111 by a first hinge 131 and extending toward the first rod 120; and a third rod 140 having one end hinged to the rear end of the second leg 112 by a second hinge 141 and extending toward the first rod 120 ; includes

Referring to FIG. 3 , the gripper 110 includes a first leg 111 and a second leg 112 , which are two left and right legs arranged in the form of tongs with front ends close to each other and rear ends open to each other. The first leg 111 and the second leg 112 are hinged to each other by a hinge shaft 113 coupled to opposite sides of the first leg and the second leg adjacent to the tip of each leg. By one-way rotation of the first leg 111 and the second leg 112 about the hinge shaft 113, the front ends 111a and 112a of the legs are close to each other to grip the specimen, and in the opposite direction By the rotation of the front end portions (111a, 112b) of the legs are spaced apart from each other, it is possible to release the specimen.

In addition, at the rear of the hinge shaft 113 , the first leg 111 and the second leg 112 are respectively coupled to opposite sides of the hinge shaft 113 to connect the first leg 111 and the second leg 112 . A member 114 is located. That is, the first leg 111 and the second leg 112 are connected to each other by the hinge shaft 113 and the elastic member 114 . The elastic member 114 serves to smoothly grip the specimen 310 by resisting or helping the movement of the first leg and the second leg. That is, if the elastic member 114 is present, the first leg 111 and the second leg 112 can be moved by resisting the pressing force, so that the specimen 310 can be pressed more strongly by the resistance force. Accordingly, the elastic member 114 is a member necessary for more reliable and stable gripping.

In the drawings, the elastic member 114 is in the form of a coil spring, but other types of elastic members are also possible. For example, a rectangular rubber block or an elastic member in the form of a snap ring may be installed between the first and second legs 111 and 112 . However, it is preferable to use the elastic member 114 in the form of a coil spring in consideration of the limited space of the gripper part 110 and the size of the strong elastic pressing force required for measuring the tensile strength.

A characteristic feature of the present invention is that three rods having a unique hinge structure are coupled to the gripper unit 110 .

That is, it is positioned between the first leg 111 and the second leg 112 of the gripper part 110 at the rear of the elastic member 114 and one end is connected to the tensile strength meter 200 to measure the tensile strength. a first rod 120 movable up and down for; a second rod 130 having one end hinged to the rear end of the first leg 111 by a first hinge 131 and extending toward the first rod 120; and a third rod 140 having one end hinged to the rear end of the second leg 112 by a second hinge 141 and extending toward the first rod 120 ; includes

In one embodiment, the first rod 120 is coupled to a vertical movement mechanism provided in the tensile strength measuring instrument 200 or a load cell 220 connected to the vertical movement mechanism. That is, the first rod 120 is a portion to which a tensile force (upward force) is applied by the tensile strength measuring device 200 . In this embodiment, the load cell 220 is coupled to a moving member 230 that is slidably coupled to the tensile strength measuring device. The moving member 230 is lifted and moved by a driving unit (not shown), and accordingly, the load cell 220 and the first rod 120 connected thereto can be moved up and down.

The second rod 130 and the third rod 140 are respectively coupled to rear ends of the first leg 111 and the second leg 112 of the gripper unit 110 by a hinge. That is, one end of the second rod 130 is hinged by the first hinge 131 to the rear end opposite to which the specimen of the first leg 111 is gripped. One end of the third rod 140 is hinged by a second hinge 141 to the rear end of the second leg 112 opposite to the specimen gripping part. The second rod 130 and the third rod 140 extend toward the first rod 120 disposed between the first and second legs. The lengths of the second rod 130 and the third rod 140 need to be the same in order to transmit a uniform tensile force to the specimen during the tensile test.

The first rod 120 , the second rod 130 , and the third rod 140 are coupled to each other by a unique hinge structure. That is, the other ends of the first rod 120 , the second rod 130 , and the third rod 140 are hinged together by a third hinge 121 having one hinge shaft. With this structure, when the first rod 120 moves up and down between the first leg 111 and the second leg 112, the second rod 130 and the third rod 140 move 1 It moves up and down by following (interlocking) the vertical movement of the rod 120. In addition, the first leg 111 and the second leg 112 hinged to the second rod 130 and the third rod 140, respectively, are also moved interlockingly.

4 is a schematic diagram showing in more detail the direction of force during the operation before and after operation of the fixed gripper for a tensile strength measuring instrument of the present invention. FIG. 3 is a view corresponding to the third figure when the specimen of FIG. 4 is pulled. An operation process according to the configuration of the fixed gripper for a tensile strength measuring instrument of the present invention will be described in detail with reference to FIGS. 3 and 4 .

First, from the state before the operation of FIG. 2, when the vicinity of the rear end of the first leg 111 and the second leg 112 is pressed as shown in FIG. 4(a), the first leg 111 and the second leg 112 ) moves to the inside of the gripper part 110 while pressing and contracting the elastic member 114, and conversely, the front ends 111a and 112a of the first leg 111 and the second leg 112 are Due to the hinge rotation action of the hinge shaft 113 , the gripper part 110 is opened to the outside. The specimen 310 may be inserted through this gap.

Meanwhile, as a test target in the embodiment of FIG. 2 , a single battery 300 used for manufacturing a secondary battery battery pack was selected. A metal plate 310 for connection to another battery is welded to the upper surface of the battery 300 . In order to determine whether the welding strength of the metal plate 310 is appropriate, the metal plate 310 is fixed with the gripper part 110 and a tensile force is applied until the metal plate 310 is separated from the battery 300. Repeat experiment can be done Usually, a straight metal plate 310 is welded to the upper surface of the battery, but for a tensile test, the metal plate 310 is manufactured in an L-shaped bent shape, and the upwardly bent metal plate portion is gripped by the gripper unit 110 . Thus, the tensile strength was measured.

When the specimen is sandwiched between the tip ends 111a and 112a of the first leg 111 and the second leg 112 as shown in Fig. 4(a), the elastic member 114 expands to its original shape by the restoring force. , the rear ends of the first leg 111 and the second leg 112 connected to the elastic member 114 are widened accordingly (FIG. 4(b)). When the rear ends of the first leg 111 and the second leg 112 are widened, on the contrary, the front ends of the first leg 111 and the second leg 112 approach closer, so that the specimen 310 is tight between the front ends. inserted and firmly fixed.

Then, as shown in FIG. 4(c), when the first rod 120 positioned between the first leg 111 and the second leg 112 is pulled upward, the first rod by the third hinge 121 The second rod 130 and the third rod 140 hinged to 120 also move upward. That is, the second rod 130 and the third rod 140 are folded toward the elastic member 114 side of the first leg 111 and the second leg 112 according to the upward movement of the first rod 120 . It moves away from the elastic member 114 until it is parallel to the rear end. In addition, as the second rod 130 and the third rod 140 move, the first leg of the gripper part 110 hingedly coupled to one end of the second rod 130 and the third rod 140, respectively. (111) and the rear end of the second leg 112 also receives a force in the left and right direction. That is, the gripper part 110 is fixed by biting the specimen 310 at the distal ends of the first leg 111 and the second leg 112 so that the first leg 111 and the second leg 112 move upward. Since it cannot move, the rear ends of the first and second legs 111 and 112 are further widened by the hinge rotation of the hinge shaft 113 . In other words, the upward movement force of the first rod 120 is converted into left and right outward forces of the first and second legs 111 and 112 to receive the force in the left and right directions. According to this force, the rear ends of the first leg 111 and the second leg 112 resist the pressing force of the elastic member 114 to move left and right, and the hinge shaft 113 is rotated The gap between the tips of the first and second legs (111, 112) is further narrowed, thereby tightening the specimen more strongly. 3 and 4 (c) show the tightening state of these specimens in detail with arrows indicating the direction of the force.

5 and 6 show a state in which the state of FIGS. 3 and 4 (c) is implemented in the tensile test measuring device 200, and FIG. 5 is a perspective view showing a state after operation in which a tensile force is applied to the fixed gripper 100 , Figure 6 is a front view.

The vertical movement stroke of the first rod 120 is appropriately selected according to the size and material of the specimen applied to the tensile test. Although the moving stroke of the first rod 120 is exaggerated in the drawing, in the case of a small specimen, the stroke is not so large in reality. However, the other end of the first rod 120 coupled to the third hinge 121 is located below the rear end of the first leg 111 and the second leg 112 (state of FIG. 4(a)). When moving beyond the position parallel to the rear end (state of Fig. 4(c)) to a position above the rear end, the front ends of the first leg 111 and the second leg 112 in the direction of the force are rather widened. Therefore, the force that clamps the psalm may be weakened. Therefore, the vertical movement stroke of the first rod 120 is the size of the specimen within a range from a position below the rear end of the first leg 111 and the second leg 112 to a position at least parallel to the rear end. You need to set it up accordingly. For example, the first rod 120 may move only from a position where the other end is adjacent to the elastic member 114 to a position parallel to the rear ends of the first leg 111 and the second leg 112 . Of course, the movement stroke may be changed in consideration of the length of the first to third rods, the size or length of the specimen, and the like. For example, depending on the specimen, the first rod 120 does not move to a position parallel to the rear end of the first leg 111 and the second leg 112, but only moves to a position below the rear end of the path. It may have an up and down movement stroke.

On the other hand, as shown in FIG. 7 , it is preferable that a protrusion T capable of gripping the specimen is formed on the tip portions 111a and 112a of the first leg 111 and the second leg 112 for holding the specimen.

(Second embodiment)

Fig. 8 is a perspective view showing a tensile strength measuring device according to a second embodiment of the present invention and a state before operation of the fixed gripper for the tensile strength measuring device. About this 2nd Embodiment, description of the same part as 1st Embodiment is abbreviate|omitted, and only a different part will be demonstrated.

The first rod 120 may be configured in the form of a single rod as shown in FIG. 2 , or may be configured as two rods, an upper rod 120a and a lower rod 120b, as shown in FIG. 8 . When the upper rod 120a and the lower rod 120b are hinged by the fourth hinge 122 , the first rod 120 is the upper rod 120a and the lower rod 120b by a fourth hinge shaft 122 . It becomes a structure that can be rotated around In the hinge coupling structure in which the fourth hinge 122 is added, the upper rod 120a and the lower rod 120b when the tensile test target under the first rod 120 is not aligned with the lower end of the gripper unit 110 . It can help to align with the specimen under tensile test by moving the hinge. However, since the gripper part 110 and the first rod 120 are in a state in which hinge movement is possible by the first to third hinges 121, 131, and 141, the specimen alignment operation is also performed by adjusting the position through the first to third hinges. can be done The more important reason for placing the fourth hinge 122 is that even if the gripper part 110 is positioned with respect to the inspection object in a slightly inclined state in a diagonal rather than vertical due to the hinge coupling, the first rod 120 ) to help naturally set the gripper unit 110 to an upright state while pulling upwards. That is, when the first rod 120 is formed of the upper rod 120a and the lower rod 120b with the fourth hinge 122 interposed therebetween, compared to the case where the first rod 120 is formed as a single rod, when the gripper part 110 moves left and right, the Since the fourth hinge 122 can smoothly absorb the force in the moving direction, the upright state of the gripper of FIG. 6 can be realized more naturally.

(Third embodiment)

A third embodiment of the present invention will be described with reference to Figs.

The present embodiment is different from the first embodiment in that the support member 250 for guiding the vertical movement of the first rod 120 is coupled to the first rod 120 .

As shown, the support member 250 is coupled to one side of the first rod 120 in a direction transverse to the first rod 120 . Both ends of the support member 250 are slidably coupled to the tensile strength meter frame 210 . Preferably, the support member 250 is installed across both ends of the support member 250 on a rail part (not shown) built into the tensile strength meter 200, and when the first rod 120 moves up and down, the support member ( As the 250 slides along the rail unit, the vertical movement of the first rod 120 may be guided.

The support member 250 may be applied whether the first rod 120 is composed of a single rod or is composed of two rods, an upper rod 120a and a lower rod 120b. As described above, when the lower gripper part 110 is inclined, the first rod 120 may receive a force in an inclined direction, so that the support member 250 stably holds the first rod 120 during vertical movement. By supporting and guiding with the , it is possible to partially offset or absorb this force.

Hereinafter, the fixed gripper 100 and the operation of the tensile strength measuring device 200 including the fixed gripper 100 will be described in detail with reference to FIGS. 2 to 6 .

As a test object, a single battery 300 used for manufacturing a secondary battery battery pack was selected. A metal plate 310 for connection to another battery is welded to the upper surface of the battery 300 .

For the tensile strength test, first, the battery 300 to be tested is fixed to the lower chuck 240 installed at the lower end of the frame 210 of the tensile strength tester 200 .

Thereafter, by pressing the rear ends of the first and second legs 111 and 112 inward, the front ends of the first and second legs 111 and 112 are widened so that the metal plate 310 as a specimen is placed between the front ends 111a and 112a. put it on

In the process of fitting the metal plate 310 to the front end, the elastic member 114 is compressed, so that the elastic member 114 presses the rear ends of the first and second legs 111 and 112 by the restoring force to spread them apart. Accordingly, the front ends of the first and second legs 111 and 112 are more reliably supported by sandwiching the metal plate 310 .

The alignment of the gripper part 110 with respect to the specimen 310 is performed by adjusting the position by the first to third hinges 121, 131, 141 or the gripper part (with reference to the fourth hinge 122 installed on the first rod 120). 110) by moving left and right.

When the specimen 310 is fixed to the gripper unit 110 , the first rod 120 is moved upward by the driving unit provided in the tensile strength tester 200 . One end of the first rod is coupled to the load cell 220 , and the load cell 220 measures the tensile force or tensile strength applied to the first rod 120 . The load cell 220 is coupled to a movable member (cross head) 230 installed in the tensile strength measuring device 200 , and the cross head 230 can move up and down by a predetermined driving unit.

When the first rod 120 moves upward, the rear ends of the first and second legs 111 and 112 are further widened, and accordingly, the front ends of the first and second legs 111 and 112 further tighten the specimen (Fig. see 4(c)).

The load applied to the first rod 120 may be measured by the load cell 220 to measure the welding strength of the metal plate 310 as a specimen.

As described above, in the present invention, as the first rod 120 is pulled upward, the specimen fixed to the gripper part 110 receives a force in the left and right inward directions as shown in FIGS. 3 and 4 (c) and becomes stronger. tightened Therefore, it is possible to prevent the specimen from escaping during the tensile test.

Above, the present invention has been described in more detail through drawings and examples. However, the configuration described in the drawings or embodiments described in the present specification is only one embodiment of the present invention and does not represent all the technical spirit of the present invention, so at the time of the present application, various equivalents and It should be understood that there may be variations.

100: fixed gripper
110: gripper part
111: first leg
112: second leg
113: hinge shaft
114: elastic member
120: first rod
120a: upper rod
120b: lower rod
121: third hinge
122: fourth hinge
130: second rod
131: first hinge
140: second load
141: second hinge
200: tensile strength measuring instrument
210: frame
220: load cell
230: moving member (cross head)
240: lower chuck
250: support member

Claims (13)

The first and second legs are arranged in the form of tongs with the front ends close to each other and the rear ends spread apart, and the first and second legs are coupled to opposite sides of the first and second legs adjacent to the front ends, respectively. a gripper part including a hinge shaft for hinge-joining the legs, and elastic members coupled to opposite sides of the first and second legs from the rear of the hinge shaft to connect the first and second legs;
a first rod positioned between the first leg and the second leg at the rear of the elastic member and having one end connected to a tensile strength measuring device to move up and down to measure the tensile strength;
a second rod having one end hinged to the rear end of the first leg by a first hinge and extending toward the first rod; and
a third rod having one end hinged to the rear end of the second leg by a second hinge and extending toward the first rod; including,
The other ends of the first rod, the second rod and the third rod are hinged together by a third hinge having a single hinge axis, and as the first rod moves up and down between the first and second legs, A fixed gripper for a tensile strength measuring device in which the second and third rods, and the first and second legs are interlocked.
The method of claim 1,
The elastic member is a fixed gripper for a tensile strength measuring device that is one of a coil spring, a rubber block, and a snap ring.
The method of claim 1,
One end of the first rod is installed in the tensile strength measuring device, and the fixed gripper for the tensile strength measuring device is coupled to the load cell moving up and down by the driving unit.
4. The method of claim 3,
The load cell is a fixed gripper for a tensile strength measurement device coupled to a movable member slidably coupled to the tensile strength measurement device.
According to claim 1,
The first rod is a tension having a vertical movement stroke in which the other end of the first rod coupled to the third hinge moves from a position below the rear end of the first leg and the second leg to a position parallel to the rear end Fixed grippers for strength measuring instruments.
6. The method of claim 5,
The first rod is a fixed gripper for a tensile strength measuring device having a vertical movement stroke in which the other end of the first rod coupled to the third hinge moves from a position adjacent to the elastic member to a position parallel to the rear end.
6. The method of claim 5,
When the first rod is positioned adjacent to the elastic member, the first leg and the second leg are fixed grippers for a tensile strength measuring device so as to contract the elastic member therebetween;
6. The method of claim 5,
When the first rod is positioned parallel to the rear end of the first leg and the second leg, the first leg and the second leg are a fixed gripper for a tensile strength measuring device that opens so that the elastic member therebetween expands;
The method of claim 1,
A fixed gripper for a tensile strength measuring instrument in which a protrusion for holding a specimen is formed on the specimen contact surface of the tip ends of the first leg and the second leg for holding the specimen.
The method of claim 1,
The first rod is composed of an upper rod and a lower rod, and the upper rod and the lower rod are hinged by a fourth hinge. A fixed gripper for a tensile strength measuring device.
According to claim 1,
A support member coupled to the first rod in a direction transverse to the first rod and having both ends slidably coupled to a rail part built in the tensile strength measuring device is provided, and by sliding of the support member, the first A fixed gripper for a tensile strength measuring instrument that guides the up-and-down movement of the rod.
A tensile strength measuring device having the fixed gripper for the tensile strength measuring device of claim 1.
The fixed gripper for a tensile strength measuring device of claim 1, a load cell connected to one end of the first rod, a vertical movement mechanism of the load cell, a lower chuck for fixing the specimen, and a fixed gripper for the tensile strength measuring device, a load cell, and a load cell Tensile strength measuring device including a frame for accommodating the vertical movement mechanism and the lower chuck.

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