A calibration device for a concrete rebound hammer

Abstract

The present application relates to a kind of calibration device for concrete rebound hammer, including device support, spring seat is provided on device support, force spring is equipped with in the direction of movement of spring seat, one end of force spring is the force transmission end for with the force transmission of rebound hammer cooperation, the other end of force spring is provided with the spring compression amount adjusting structure for adjusting the compression amount of force spring, calibration device also includes the length measurement structure for measuring the compression length of force spring in calibration process.The present application provides a kind of calibration device for concrete rebound hammer, which can realize the calibration of rebound hammer without disassembling rebound hammer.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of calibration device for concrete rebound hammer in calibration verification field. BACKGROUND

[0002] Concrete rebound hammer is a kind of spring-driven hammer, hammer is hit through impact rod, concrete surface is hit, and concrete surface produces elastic deformation to absorb energy, and hammer rebounds, and the hardness of concrete is characterized according to energy loss.The principle used is, the harder the concrete, the less energy the elastic deformation of concrete absorbs, and the less energy lost during the impact of hammer.

[0003] The working process of concrete rebound hammer is as shown in Figure 1 To clearly show the problem, the first state, the second state, the third state, the fourth state and the fifth state occur in time sequence, when working, first, the height of hammer 16 is lifted, as shown in the first state, hammer spring 15 stores energy, and the end of impact rod 2 away from hammer is in contact with concrete surface.Subsequently, hammer 16 is released, and hammer moves towards impact rod under the guidance of guide rod 19, as shown in the second state;then, the lower end surface 18 of hammer hits impact rod 2, and impact rod hits concrete, as shown in the third state;then, as shown in the fourth state, hammer starts to rebound away from impact rod;finally, as shown in the fifth state, hammer reaches the highest rebound position.

[0004] In prior art, the energy loss of hammer is characterized by the following measurement method, i.e., the height difference of hammer in the first state and the fifth state is measured, and the rebound value is calculated by the change of energy in the two states, the difference between the sum of gravitational potential energy of hammer in the first state and the elastic potential energy of spring in the first state and the sum of gravitational potential energy of hammer in the fifth state and the elastic potential energy of spring in the fifth state is the change of energy in the two states.It can be seen that whether the rebound hammer is accurate mainly depends on the spring in the rebound hammer, according to corresponding calibration verification requirements, the rebound hammer needs to be calibrated regularly, and the calibration of rebound hammer is essentially the calibration of spring in it, and in prior art, the calibration method of rebound hammer is to completely disassemble the rebound hammer, then take out the hammer spring in the rebound hammer, exert standard weight on the hammer spring, and judge whether the elastic coefficient of hammer spring can meet the use precision according to the stretching length of hammer spring.This calibration method has the following problems:1) disassembling the rebound hammer increases the calibration difficulty;2) after the hammer spring is taken out from the rebound hammer, it is separated from its real working environment, and even if the calibration of spring is completed, whether the hammer spring is accurate after being installed in the rebound hammer is still unknown. SUMMARY

[0005] The present application aims to provide a calibration device for a concrete rebound hammer, which can calibrate the rebound hammer without disassembling the rebound hammer.

[0006] To solve the above technical problems, the technical solutions in the present application are as follows:

[0007] The calibration device for a concrete rebound hammer comprises a device support, a spring seat is arranged on the device support, a force measuring spring is movably arranged in the spring seat in a guide manner, one end of the force measuring spring is a force transmission end for cooperating with the rebound hammer, the other end of the force measuring spring is provided with a spring compression amount adjusting structure for adjusting the compression amount of the force measuring spring, and the calibration device further comprises a length measuring structure for measuring the compression length of the force measuring spring during calibration.

[0008] The force measuring spring is horizontally arranged.

[0009] A rebound hammer placing table for horizontally placing the rebound hammer is arranged on one side of the spring seat of the device support.

[0010] The calibration device further comprises an impact ball for transmitting force between the rebound hammer and the force transmission end.

[0011] A counterforce support is arranged on the device support, the counterforce support and the spring seat are located on the two sides of the axial direction of the rebound hammer, a force sensor is arranged between the counterforce support and the rebound hammer, and a supporting rolling body for reducing the friction between the rebound hammer and the rebound hammer placing table is arranged on the rebound hammer placing table.

[0012] The spring seat comprises a top seat and a bottom seat, a spring top rod is movably arranged on the top seat in a guide manner along the axial direction of the spring, the spring top rod is connected to the force transmission end through a spring head end pressing plate, and the spring compression amount adjusting structure is arranged on the bottom seat.

[0013] The spring compression amount adjusting structure comprises a spring tail end pressing plate and an adjusting screw rod which is threadedly connected to the bottom seat, and the adjusting screw rod is rotationally connected to the spring tail end pressing plate.

[0014] The length measuring structure comprises a laser displacement sensor arranged on the spring tail end pressing plate, the axis of the laser displacement sensor is consistent with the axis of the force measuring spring, and the spring head end pressing plate is provided with a measuring portion corresponding to the laser displacement sensor.

[0015] The beneficial effects of the present application are: when the rebound hammer is calibrated, the outward impact force of the rebound hammer is transmitted to the force measuring spring through the force transmission end, the elastic potential energy stored by the force measuring spring under pressure is the energy lost by the rebound hammer impact, which corresponds to the elastic potential energy of the rebound hammer before and after the impact, so that the rebound hammer can be calibrated without disassembling the rebound hammer, and the calibration process is simple and convenient; and the rebound hammer is calibrated in its working condition to ensure that the calibration result is consistent with the actual working condition of the rebound hammer. The spring compression amount adjusting structure adjusts the compression amount of the force measuring spring before the rebound hammer impacts, and the force measuring spring generates different stiffness to simulate different hardness of concrete. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a structural schematic diagram of the background art of the present application;

[0017] Figure 2 is a structural schematic diagram of embodiment 1 of the present application;

[0018] Figure 3 is a structural schematic diagram of embodiment 2 of the present application;

[0019] In the figure: 1, device support; 2, impact rod; 3, impact ball; 4, top seat; 5, rebound hammer; 6, spring top rod; 7, measuring part; 8, spring head end pressing plate; 9, force measuring spring; 10, spring tail end pressing plate; 11, laser displacement sensor; 12, adjusting screw; 13, base; 14, counterforce support; 15, impact hammer spring; 16, impact hammer; 18, lower end face of impact hammer; 19, guide rod; 20, force measuring sensor; 21, rebound hammer placing table; 22, supporting rolling body. DETAILED DESCRIPTION

[0020] In order to facilitate the understanding of the present application, the present application will be described in more detail below in combination with the drawings and specific embodiments. The preferred embodiments of the present application are shown in the drawings. However, the present application can be realized in many different forms and is not limited to the embodiments described in this specification. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0021] It should be noted that, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing the specific embodiments and are not intended to limit the present application.

[0022] The embodiments of the present application will be described in detail below in combination with the drawings.

[0023] Embodiment 1 of the calibration device for concrete rebound hammer in the present application is as follows Figure 2As shown: including device support 1, the device support in this embodiment is a plate structure, the device support is fixed with spring seat, the force spring 9 is movably assembled in the spring seat along the left and right directions, the spring seat includes top seat 4 and bottom seat 13, the bottom seat 13 and the top seat 4 are arranged at intervals left and right, the right end of the force spring 9 is a force transmission end for cooperating with the rebound instrument force transmission, the left end of the force spring is provided with a spring compression amount adjusting structure for adjusting the compression amount of the force spring.

[0024] The spring compression amount adjusting structure includes a spring tail end pressing plate 10 and an adjusting screw 12 threadedly connected with the bottom seat, and the adjusting screw 12 is in rotational cooperation with the spring tail end pressing plate 10. Rotating the adjusting screw 12 can drive the spring tail end pressing plate 10 to move left and right, thereby adjusting the initial compression amount of the force spring 9.

[0025] The top seat is movably assembled with a spring top rod 6 along the spring axial direction, and the spring top rod 6 is connected with the force receiving end through a spring head end pressing plate 8. The calibration device further includes a length measuring structure for measuring the compression length of the force spring during calibration, and the length measuring structure includes a laser displacement sensor 11 arranged on the spring tail end pressing plate 10, the axis of the laser displacement sensor is consistent with the axis of the force spring, and the spring head end pressing plate 8 has a measuring portion 7 arranged correspondingly with the laser displacement sensor. The laser displacement sensor emits laser light towards the measuring portion on the right side, and the compression amount change of the force spring is obtained through the reflection of the measuring portion.

[0026] The device support is provided with a counterforce support 14, the counterforce support 14 and the spring seat are located on both sides of the axial direction of the rebound instrument, and a force sensor 20 is arranged between the counterforce support 14 and the rebound instrument 5, and a support rolling body 22 for reducing the friction between the rebound instrument and the rebound instrument placing table is arranged on the rebound instrument placing table 21. The calibration device further includes an impact ball 3 for transmitting force between the rebound instrument and the force transmission end.

[0027] The initial prestress of the force measuring spring is adjusted by the spring compression amount adjusting structure pressing the force measuring spring, and the force can be directly displayed by the force sensor, so as to judge the stiffness of the force measuring spring. When the rebound apparatus is calibrated, the initial force of the impact ball on the impact rod is changed through multi-point calibration, so as to simulate the concrete with different stiffness and hardness. For example, the position of the elastic potential energy of the force measuring spring is first adjusted to zero, at this time, the impact ball is in contact with the impact rod, and the reading of the force sensor is zero, which indicates that the force measuring spring is not compressed. The trigger of the rebound apparatus is pulled manually or mechanically, the impact hammer spring in the rebound apparatus drives the impact hammer to impact the impact rod, and then the impact rod impacts the force measuring spring through the impact ball. After the force measuring spring is impacted, the energy is stored, the compression amount of the force measuring spring is measured by the length measuring structure, the energy stored in the force measuring spring is calculated according to the compression amount, the energy loss of the rebound apparatus in the collision process is calculated according to the position of the impact hammer in the rebound apparatus, and the elastic potential energy difference before and after the impact of the rebound apparatus is calculated. The elastic potential energy difference before and after the impact of the rebound apparatus is compared with the energy stored in the force measuring spring, so as to calibrate whether the rebound apparatus meets the requirements.

[0028] During the whole calibration process, the impact ball, the rebound apparatus and the force measuring spring are arranged horizontally, the gravitational potential energy of each component does not change, and the influence of the gravitational potential energy of each component on the calibration process is avoided. The spring compression amount adjusting structure can compress the force measuring spring before calibration, change the initial contact force of the impact ball and the impact, and simulate the concrete with different hardness and stiffness, so as to realize the calibration process of the rebound apparatus under different stiffness states.

[0029] In other embodiments of the present application: the compression amount adjusting structure can also be an electric mode, the initial compression amount of the force measuring spring is adjusted by driving the pressing plate through the motor; the impact hammer can also not be provided, at this time, the impact rod of the rebound apparatus can directly transmit force to the force measuring spring; the length measuring structure can also not be the laser displacement sensor mode, for example, a scale is arranged on the spring seat, a indicating needle is arranged on the force measuring spring and matched with the scale, and the compression amount of the force measuring spring is judged by the indication of the indicating needle to the scale.

[0030] Embodiment 2 of the calibration device for the concrete rebound apparatus is shown in Figure 3 The difference between embodiment 2 and embodiment 1 is that in the present embodiment, the counterforce support, the force sensor and the rebound apparatus placing table are not provided. When the rebound apparatus 5 is calibrated, the operator needs to hold the rebound apparatus 5 to realize the calibration of the rebound apparatus.

[0031] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A calibration device for a concrete rebound hammer, comprising a device holder, characterised in that: The device support is provided with a spring seat, a force measuring spring is movably arranged in the spring seat, one end of the force measuring spring is a force transmission end for cooperating with a rebound instrument, the other end of the force measuring spring is provided with a spring compression amount adjusting structure for adjusting the compression amount of the force measuring spring, the calibration device further comprises a length measuring structure for measuring the compression length of the force measuring spring during calibration, the force measuring spring is horizontally arranged, the device support is provided on one side of the spring seat with a rebound instrument placement table for horizontally placing the rebound instrument, the calibration device further comprises a striking ball for transmitting force between the rebound instrument and the force transmission end, the device support is provided with a counterforce support, the counterforce support and the spring seat are located on both sides of the axial direction of the rebound instrument, a force sensor is arranged between the counterforce support and the rebound instrument, and the rebound instrument placement table is provided with a support rolling body for reducing the friction between the rebound instrument and the rebound instrument placement table.

2. The calibration device of claim 1, wherein: The spring seat comprises a top seat and a bottom seat, a spring top rod is movably arranged on the top seat along the axial direction of the spring, the spring top rod is connected with the force receiving end through a spring head end pressing plate, and the spring compression amount adjusting structure is arranged on the bottom seat.

3. The calibration device of claim 2, wherein: The spring compression amount adjusting structure comprises a spring tail end pressing plate and an adjusting screw rod which is threadedly connected with the bottom seat, and the adjusting screw rod is rotationally matched with the spring tail end pressing plate.

4. The calibration device of claim 3, wherein: The length measuring structure comprises a laser displacement sensor arranged on the spring tail end pressing plate, the axis of the laser displacement sensor is consistent with the axis of the force measuring spring, and the spring head end pressing plate is provided with a measuring portion corresponding to the laser displacement sensor.

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