A three-point bending test device

Abstract

This utility model relates to a three-point bending test device, comprising a base, a lower support, support rollers, and a pressure head; the lower support is disposed on the left and right sides of the upper part of the base; the support rollers are respectively disposed on the top of the upper support; the pressure head is disposed above the center of the area between the two support rollers; a baffle is fixedly disposed between the rear tops of the two upper supports. This utility model can effectively avoid safety problems such as brittle specimens breaking off and injuring people during the three-point bending test.

Description

Technical Field

[0001] This utility model relates to the field of three-point bending measurement technology, and in particular to a three-point bending test device. Background Technology

[0002] The three-point bending test is used to detect the fracture properties of materials. A three-point bending test fixture typically consists of an upper indenter and two support rollers. The distance between the two support rollers is called the span. During the test, the specimen is placed on the two support rollers, and pressure is applied to the specimen using the upper indenter. Simultaneously, the amount of crack propagation is measured. The fixture is one of the important devices for measuring the crack arrest characteristics of materials.

[0003] The existing three-point bending fixture direct-drive testing machine can perform three-point bending tests, but due to design reasons, it cannot protect the safety of operators. Especially when performing fracture tests on brittle specimens, it is easy to cause the specimen to break off brittlely and pop out, injuring the testing personnel and causing safety accidents. Summary of the Invention

[0004] To solve the above-mentioned technical problems, this utility model provides a three-point bending test device, which can effectively avoid safety problems such as brittle specimens breaking off and injuring people during the three-point bending test.

[0005] The technical solution adopted in this invention is as follows: The present invention provides a three-point bending test device, comprising a base, a lower support, support rollers, and a pressure head; the lower support is disposed on the left and right sides of the upper part of the base; the support rollers are respectively disposed on the top of the upper support; the pressure head is disposed above the middle of the area between the two support rollers; characterized in that: a baffle is fixedly disposed between the rear tops of the two upper supports.

[0006] Furthermore, the base is an I-beam structure.

[0007] Furthermore, the bottom of the lower support has a T-shaped groove corresponding to the upper part of the base; the lower support is slidably connected to the upper part of the base through the T-shaped groove.

[0008] Furthermore, the lower support has threaded holes on its front and rear sides that correspond to the front and rear end faces of the upper part of the base.

[0009] Furthermore, the lower two sides of the baffle are respectively provided with strip grooves; the end of the support roller corresponding to the baffle is inserted into the strip groove.

[0010] Furthermore, the top of the lower support has a U-shaped groove for placing the support roller.

[0011] Furthermore, the front and rear ends of the support roller are respectively connected to the middle of the front and rear sides of the lower support by springs.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. This utility model can effectively reduce the adjustment time of the span between the two support rollers each time the sample size is changed.

[0013] 2. This utility model, through the use of a baffle structure design, can effectively prevent brittle fracture samples from flying and injuring people, thus avoiding unnecessary personal injury. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 for Figure 1 Front view structural diagram; Figure 3 for Figure 1 Side and front view structural diagrams of the central base; Figure 4 for Figure 1 Side and front view structural schematic diagrams of the lower and middle supports; Figure 5 for Figure 1 Side and front view structural schematic diagrams of the middle support roller; Figure 6 for Figure 1 A schematic diagram of the main structure of the middle baffle; Figure 7 This is a schematic diagram of the bolts connecting the baffle and the support roller.

[0015] In the attached drawings, the following reference numerals are used: 1-base; 2-lower support; 21-T-slot; 22-U-slot; 23-threaded hole; 3-support roller; 4-baffle; 41-strip groove; 5-upper support; 6-spring; 7-pressure roller. Detailed Implementation

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] It should be noted that in the description of this utility model, the terms "upper", "lower", "top", "bottom", "one side", "the other side", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not mean that the device or component must have a specific orientation, or be constructed and operated in a specific orientation.

[0018] See appendix Figures 1-6 The present invention proposes a three-point bending test device, comprising a base 1, a lower support 2, a support roller 3, and a pressure head. The base is an I-beam structure.

[0019] The lower supports 2 are respectively disposed on the left and right sides of the upper part of the base 1. In this embodiment, the bottom of the lower supports 2 has a T-slot corresponding to the upper part of the base 1; the lower supports 2 are slidably connected to the I-beam structure on the upper part of the base 1 through the T-slot. Before the test, the distance between the two lower supports 2 is adjusted according to the size of the sample. The center distance between the two support rollers 3 is called the span. Since the diameter of the support rollers 3 and the size of the lower supports are fixed, the span is adjusted by adjusting the distance between the lower supports 2. Adjusting the span is a necessary step before testing samples of different sizes. Using the above adjustment method can save the time of changing samples, thereby improving the testing efficiency.

[0020] The lower support 2 has threaded holes on its front and rear bottom sides that correspond to the front and rear end faces of the upper part of the base. After the lower support 2 is adjusted to a suitable position, it can be locked with bolts. The top of the lower support 2 has a U-shaped groove.

[0021] The support rollers 3 are respectively placed in the U-shaped grooves on the top of the upper support 2.

[0022] The pressure head is located in the middle of the area between the two support rollers, and the pressure head consists of an upper support 5 and a pressure roller fixed to the bottom of the upper support 5.

[0023] In this device, a baffle 8 is fixedly installed between the rear tops of the two upper supports 2 to prevent brittle fracture samples from ejecting and injuring people. The lower sides of the baffle 8 have strip grooves 81. The end of the support roller 3 corresponding to the baffle 8 is inserted into the strip groove 81, facilitating the adjustment of the support roller 3's position as the lower support moves left and right. A screw hole is provided at the end of the support roller 3 located within the strip groove. After its position is adjusted, a bolt is screwed into the screw hole at the end of the support roller 3 from outside the strip groove 41, thereby fixing the support roller 3 to the baffle 8.

[0024] In this embodiment, the front and rear ends of the support roller 3 are respectively connected to the middle of the front and rear sides of the lower support 2 by springs 6, and the support roller 3 is pulled into the U-shaped groove of the lower support 3 by the rebound force of the springs 6.

[0025] The working principle of this utility model is as follows: Connect the pressure head to the crossbeam of the crushing equipment. Place the support roller 3 into the U-shaped groove 22 of the lower support 2 and connect it with spring 6 to fix the support roller 3 to the lower support 2; place the base 1 on the actuating cylinder of the crushing equipment and fix it with bolts; slide the T-shaped groove 21 of the lower support into the upper plate of the base 1, with the side with the spring fixing nail facing inward, and slide the lower support 2 into the appropriate position. Fix the relative position of the support roller 3 and the lower support 2 with spring 6; measure the width W and thickness B of the three-point bending test. Select an appropriate span (S=4W) according to the sample width; subtract the diameter of the support roller 3 and the wall thickness of the upper end of the lower support 2 from the span length to get the distance between the two lower supports 2; raise the lower actuating cylinder until the centers of the support roller 3 and the pressure roller 7 are on the same horizontal plane; use a vernier caliper to measure the distance between the two adjacent rollers, and adjust the relative position of the lower support 2 to make the distance between the two adjacent rollers S / 2. Tighten the bolts of the lower support 2 to fix it to the base 1; adjust the extension length of the actuator cylinder so that the three-point bending specimen can be placed in the fixture, and adjust the relative position of the specimen to achieve the state where the bending test can be performed; fix the two strip grooves 81 on the baffle 8 to the ends of the two side support rollers 3 respectively, and fix them with bolts. The baffle 8 is on the side of the specimen facing the person, and then the crushing test can be performed.

[0026] Matters not covered in this utility model are common knowledge.

[0027] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Various modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A three-point bending test device comprising a base, a lower support, a supporting roller and a pressure head; the lower support is arranged on the left and right sides of the upper part of the base; the supporting roller is arranged on the top of the upper support respectively; the pressure head is arranged above the middle of the area between the two supporting rollers; characterized in that: A baffle is fixedly installed between the rear top of the upper supports on both sides.

2. The three-point bending test device according to claim 1, characterized in that: The base is an I-beam structure.

3. A three-point bending test apparatus according to claim 2, characterised in that: The bottom of the lower support has a T-shaped groove corresponding to the upper part of the base; the lower support is slidably connected to the upper part of the base through the T-shaped groove.

4. A three-point bending test apparatus according to claim 3, wherein: The lower support has threaded holes on its front and rear sides that correspond to the front and rear end faces of the upper part of the base.

5. A three-point bending test apparatus according to claim 3, wherein: The lower two sides of the baffle are respectively provided with strip grooves; the end of the support roller corresponding to the baffle is inserted into the strip groove.

6. A three-point bending device according to claim 1, characterized in that: The lower support has a U-shaped groove at the top for placing the support roller.

7. A three-point bending device according to claim 6, characterised in that: The front and rear ends of the support roller are respectively connected to the middle of the front and rear sides of the lower support by springs.

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