A mechanism sand concrete hardness detection device

Abstract

The application provides a mechanism sand concrete hardness detection device, and relates to the technical field of concrete detection.The device comprises a support chassis, a transmission belt, an elastic support frame, a cleaning brush, a hardness tester impact assembly, an adjusting frame, a pressing plate, a strain gauge and a main control box.The transmission belt is responsible for conveying concrete blocks, the elastic support frame and the cleaning brush ensure the cleaning of the transmission belt, the adjusting frame cooperates with the strain gauge and the main control box to accurately control the contact pressure, and the hardness tester impact assembly performs hardness detection.The close cooperation of various components realizes an automatic detection process, improves detection accuracy and efficiency, and reduces manual intervention.Meanwhile, the cleaning mechanism effectively cleans the residual concrete on the transmission belt, prolonging the service life of the equipment.The device is suitable for hardness detection of mechanism sand concrete and helps quality control.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of concrete detection, in particular to a machine-made sand concrete hardness detection device. BACKGROUND

[0002] In the production process of machine-made sand concrete, hardness detection is a key link to ensure that the quality of the concrete meets the standard requirements. The existing machine-made sand concrete hardness detection device, such as a hardness detection device for machine-made sand concrete production (patent number CN219890995U), usually includes a support bottom plate, a support rod, a detection table, a semi-circular baffle, an inclined frame, and a cleaning mechanism. Its working principle is to place the concrete block on the detection table, and drive the pressure block to test the hardness of the concrete through the hydraulic cylinder. After the test is completed, start the drive motor to rotate the strip-shaped cleaning brush to clean the crushed concrete debris on the detection table into the receiving frame.

[0003] However, the concrete hardness detection device has some limitations in actual use. On the one hand, during the hardness detection process, the device is not precise enough in fixing and contact pressure control of the concrete block, which may affect the accuracy of the test results. On the other hand, although the existing cleaning mechanism can clean the debris to some extent, the cleaning effect is not good, especially when multiple samples are continuously detected, residual concrete debris may interfere with subsequent detection. Furthermore, the existing device still has room for improvement in terms of automation, and the operation process is relatively cumbersome, relying heavily on human intervention, which not only reduces the detection efficiency, but also may cause deviation of the test results due to human factors.

[0004] In summary, the machine-made sand concrete hardness detection device in the prior art has basic hardness detection and cleaning functions, but still has deficiencies in detection accuracy, cleaning effect of key components, and automation level, which limits its application effect and efficiency in actual production. SUMMARY

[0005] In view of the deficiencies of the prior art, the present application provides a machine-made sand concrete hardness detection device to solve the problems raised in the background art.

[0006] To achieve the above purpose, the present application is implemented by the following technical scheme: a machine-made sand concrete hardness detection device, comprising a support chassis, a driving roller and three driven rollers are rotatably connected inside the support chassis, a transmission belt is transmissionally connected to the outer side wall of the driving roller and the driven rollers, a resilient support frame is fixedly connected to the front side wall and the rear side wall of the support chassis, a guide rod is fixedly connected inside each resilient support frame, a connecting rod is slidingly connected to the outer side wall of each guide rod, a transmission link is fixedly connected between the two connecting rods, and a cleaning brush is fixedly connected to the outer side wall of the transmission link.

[0007] The upper side wall of the support chassis is fixedly connected with a support top frame, an electric push rod is installed on the upper side wall of the support top frame, the output end of the electric push rod is fixedly connected with a connecting frame, a hardness tester impact assembly is installed on the middle of the lower side wall of the connecting frame, the hardness tester impact assembly is a key component of the Leeb hardness tester, and contains an impact body, a spring, a guide pipe, a coil component and the like. When working, the impact body impacts the surface of the measured object under the action of the spring, and the hardness value is calculated by measuring the impact speed and rebound speed of the impact body. The lower side wall of the connecting frame is fixedly connected with two adjusting frames, each adjusting frame is slidably connected with an adjusting rod inside, the lower end of the adjusting rod is fixedly connected with a pressing plate, and the lower side wall of the pressing plate is fixedly connected with a strain gauge. When the strain gauge contacts the machine-made sand concrete block, mechanical deformation occurs, the resistance value changes accordingly, and it is judged whether the pressing plate contacts the machine-made sand concrete block.

[0008] Preferably, the middle of the outer side wall of the transmission belt is provided with anti-skid lines for marking the placement position of the machine-made sand concrete block. The inside of the support chassis is fixedly connected with a support plate, and the upper side wall of the support plate is in sliding connection with the inner side wall of the transmission belt. The support plate is used for supporting the machine-made sand concrete block.

[0009] Preferably, the inside of each elastic support frame is rotatably connected with a rotating rod, the rotating rod is rotatably connected with the cleaning brush, and the rotating rod is fixedly connected with a transmission rod between the rotating rod and the connecting rod.

[0010] Preferably, the guide rod is in an arc shape, the arc shape is coincided with the middle of the rotating rod, the connecting rod can slide along the rotating rod, each connecting rod is provided with a sliding inner groove inside, the guide rod cooperates with the connecting rod through the sliding inner groove, and the outer side wall of the guide rod is provided with two supporting springs, which are respectively located on the two sides of the connecting rod and are used for stably supporting the connecting rod, so that the cleaning brush cooperates with the lower side wall of the transmission belt.

[0011] Preferably, the rear side wall of the support chassis is fixedly connected with a support rear plate, the upper side wall of the support rear plate is installed with a transmission motor and a transmission box, the output end of the transmission motor is fixedly connected with the input end of the transmission box, and the output end of the transmission box is fixedly connected with the driving roller. The transmission motor drives the driving roller to rotate through the transmission box, so as to drive the transmission belt to rotate. When the transmission belt rotates, the concrete debris falling on the transmission belt can be rotated, so as to facilitate cleaning of the transmission belt.

[0012] Preferably, the upper side wall of the cleaning brush is fixedly connected with a brush head, and the brush head cooperates with the lower side wall of the transmission belt, so as to facilitate cleaning of the transmission belt.

[0013] Preferably, the inner side wall of the adjusting frame is fixedly connected with an access resistor, the upper side wall of the adjusting rod is fixedly connected with a connecting strip, the side wall close to the access resistor of the connecting strip is fixedly connected with a contact piece, the side wall close to the access resistor of the contact piece is fixedly connected with a graphite piece, the graphite piece is in close contact with the access resistor, and the relative position between the contact piece and the access resistor changes when the adjusting rod slides up and down, so that the size of the circuit in which the access resistor accesses is changed, the sliding distance of the adjusting rod is judged by detecting the current in the circuit, and the access resistor is arranged in the shape of a character.

[0014] Preferably, the rear side of the supporting base frame is provided with a main control box, the inside of the main control box is provided with a current measuring circuit and a hardness tester main machine, the access resistor is connected in series in the current measuring circuit, the current measuring circuit measures the current in the current measuring circuit to judge the sliding distance of the adjusting rod, the hardness tester main machine collects, amplifies, processes and operates the signals transmitted by the hardness tester impact assembly, so as to obtain the hardness value and display it on the display screen. The main machine usually includes a shell, a communication socket, an impact device socket, a liquid crystal display, a keyboard and the like.

[0015] The present application provides a kind of mechanism sand concrete hardness detection device, with the following beneficial effects:

[0016] The present application can accurately control the contact pressure between the pressing plate and the concrete block through the synergistic effect of the adjusting frame and the access resistor, ensuring stable contact between the hardness tester impact assembly and the concrete block. This precise pressure adjustment mechanism effectively solves the problem of detection error caused by unstable contact pressure in the prior art, thereby significantly improving the accuracy and reliability of the detection results.

[0017] The device can clean the concrete residues on the surface of the transmission belt in real time by using the cooperation of the elastic support frame and the cleaning brush. This not only avoids the interference of residual debris on subsequent detection, but also reduces equipment wear caused by long-term accumulation, significantly prolongs the service life of the transmission belt and reduces maintenance costs. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the present application;

[0019] Figure 2 It is a front view schematic diagram of the present application;

[0020] Figure 3 It is a sectional view schematic diagram of the adjusting rod of the present application;

[0021] Figure 4 It is an internal schematic diagram of the elastic support frame of the present application;

[0022] Figure 5 is a sectional view schematic diagram of the present application;

[0023] Figure 6 is a top view schematic diagram of the present application.

[0024] Wherein, 1, support chassis; 101, support back plate; 102, support top frame; 103, support plate; 104, transmission box; 105, transmission motor; 2, transmission belt; 201, anti-skid pattern; 202, driving roller; 203, driven roller; 3, elastic support frame; 301, rotating rod; 3011, transmission rod; 302, connecting rod; 3021, sliding inner groove; 303, guide rod; 3031, support spring; 4, main control box; 5, electric push rod; 501, connecting frame; 502, hardness tester impact assembly; 6, adjusting frame; 601, adjusting rod; 6011, connecting strip; 6012, contact piece; 602, pressing plate; 603, strain gauge; 604, access resistor; 7, cleaning brush; 701, brush head; 702, transmission connecting rod. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application.

[0026] Embodiment one:

[0027] The embodiment of the present application provides a mechanism sand concrete hardness detection device, such as Figure 1 , Figure 5 and Figure 6As shown, including support chassis 1, support chassis 1 as the entire device foundation support structure, made of high-strength steel, has good stability and carrying capacity, in the inside of support chassis 1, rotatingly connected with a driving roller 202 and three driven rollers 203. Driving roller 202 is connected with support chassis 1 through bearing, located in the middle of support chassis 1 rear position; three driven rollers 203 are symmetrically installed on both sides of driving roller 202, forming a stable transmission structure, the outer wall of driving roller 202 and driven roller 203 is drivingly connected with transmission belt 2, transmission belt 2 is made of engineering plastic, can maintain shape stability when bearing large load, not easy to deform, the outer wall of transmission belt 2 is evenly provided with anti-skid lines 201, the anti-skid lines 201 are parallel arranged strip structure, support plate 103 is also fixedly connected in the inside of support chassis 1, the support plate 103 is made of thick steel plate, located below the transmission belt 2, the upper wall and the inner wall of transmission belt 2 are slidingly connected, providing additional support for transmission belt 2, ensuring its stability during operation, the rear wall of support chassis 1 is fixedly connected with support rear plate 101, the upper wall of support rear plate 101 is installed with transmission motor 105 and transmission box 104, the output end of transmission motor 105 is fixedly connected with the input end of transmission box 104, the output end of transmission box 104 is fixedly connected with driving roller 202. When the transmission motor 105 is energized and started, the driving roller 202 is driven to rotate stably through the speed reduction and torque increasing effect of transmission box 104, and then drives the transmission belt 2 to rotate continuously along the driving roller 202 and driven roller 203, providing power support for the subsequent conveying and detection of machine-made sand concrete block.

[0028] The front wall and the rear wall of support chassis 1 are fixedly connected with elastic support frame 3, the elastic support frame 3 is made of spring steel material with good elastic performance, such as Figure 4As shown, the inner part of each elastic support frame 3 is fixedly connected with a guide rod 303, the guide rod 303 is arranged in an arc shape, the circular shape of the arc shape coincides with the middle part of the rotating rod 301, the material is high-strength alloy steel, the surface is subjected to stress relief annealing treatment, so as to ensure the dimensional stability and anti-deformation ability in the long-term use process. The outer side wall of the guide rod 303 is slidably connected with a connecting rod 302, the inner part of each connecting rod 302 is provided with a sliding inner groove 3021, the shape of the sliding inner groove 3021 matches the arc shape of the guide rod 303, so that the connecting rod 302 can smoothly slide along the guide rod 303. The outer side wall of the guide rod 303 is provided with two supporting springs 3031, the two supporting springs 3031 are respectively located on the two sides of the connecting rod 302, the supporting spring 3031 is made of high-quality piano steel wire material, has good elasticity and fatigue resistance, and provides stable elastic support force for the connecting rod 302. The inner part of each elastic support frame 3 is also rotatably connected with a rotating rod 301, the rotating rod 301 is rotatably connected with the cleaning brush 7, the rotating rod 301 is fixedly connected with a transmission rod 3011 between the connecting rod 302, the transmission rod 3011 is made of high-strength aluminum alloy material, has the characteristics of light weight and high strength. The upper side wall of the cleaning brush 7 is fixedly connected with a brush head 701, the brush head 701 is made of wear-resistant nylon fiber, the hardness and density are accurately designed, and the concrete residues on the lower side wall of the transmission belt 2 can be effectively cleaned. The two connecting rods 302 are fixedly connected with a transmission connecting rod 702, the material of the transmission connecting rod 702 is the same as that of the connecting rod 302, in this way, when the transmission belt 2 drives the concrete residues below it to move during operation, the connecting rod 302 slides on the guide rod 303, at the same time, the rotating rod 301 is driven to rotate through the transmission rod 3011, the brush head 701 is in close contact with the lower side wall of the transmission belt 2, the concrete residues attached to the transmission belt 2 are cleaned in time, the cleanliness of the transmission belt 2 is ensured, the influence of the residues on the subsequent detection process is avoided, and the service life of the transmission belt 2 is also prolonged.

[0029] The upper side wall of the support base frame 1 is fixedly connected with a support top frame 102, the support top frame 102 adopts high-strength steel structure, has good vertical support ability and anti-lateral deformation ability, and the upper side wall is provided with an electric push rod 5, Figure 2 As shown, the output end of the electric push rod 5 is fixedly connected with a connecting frame 501, the connecting frame 501 is welded by thick steel plates, has high strength and rigidity. The lower side wall of the connecting frame 501 is provided with a hardness tester impact assembly 502 in the middle, the hardness tester impact assembly 502 is a key component of the Leeb hardness tester, mainly composed of an impact body, a spring, a guide pipe and a coil component. The lower side wall of the connecting frame 501 is also fixedly connected with two adjusting frames 6,

[0030] As shown, Figure 3As shown, the adjusting frame 6 is made of aluminum alloy material, has the characteristics of light weight and high strength, and its internal structure is optimized for the sliding installation of the adjusting rod 601. The inside of each adjusting frame 6 is slidingly connected with an adjusting rod 601, which is made of a steel rod with a hardened surface, has good wear resistance and deformation resistance. The lower end of the adjusting rod 601 is fixedly connected with a pressing plate 602 made of high-strength steel material, the surface of which is treated to prevent rust, and the lower side wall thereof is fixedly connected with a strain gauge 603, which is selected from high-sensitivity metal strain gauges and can accurately convert the mechanical deformation of the pressing plate 602 when it contacts the machine-made sand concrete block into a change in resistance value. The inner side wall of the adjusting frame 6 is fixedly connected with an access resistor 604, which is arranged in the shape of a Chinese character and is made of a high-precision metal film resistor with stable resistance. The upper side wall of the adjusting rod 601 is fixedly connected with a connecting strip 6011, the side wall of the connecting strip 6011 close to the access resistor 604 is fixedly connected with a contact piece 6012, the side wall of the contact piece 6012 close to the access resistor 604 is fixedly connected with a graphite piece, which has good conductivity and wear resistance and is tightly attached to the access resistor 604. A spring is arranged between the adjusting rod 601 and the upper inner wall of the adjusting frame 6, and the spring force is accurately calculated to make the adjusting rod 601 have appropriate supporting force on the machine-made sand concrete block. When it is necessary to detect the machine-made sand concrete block, first place the machine-made sand concrete block on the transmission belt 2, and the transmission belt 2 will convey it to the detection position. At this time, the electric push rod 5 receives the control signal and drives the connecting frame 501 to move downward, and the connecting frame 501 drives the hardness tester impact assembly 502 and the pressing plate 602 to move downward synchronously. When the pressing plate 602 contacts the surface of the machine-made sand concrete block, the strain gauge 603 produces mechanical deformation, and its resistance value changes. After the detection circuit detects this change, it is fed back to the control circuit. At the same time, the adjusting rod 601 slides upward under the pressure of the pressing plate 602, the contact piece 6012 slides along the access resistor 604, and the resistance value of the access resistor 604 in the access circuit changes. The current measurement circuit detects the change of the current, calculates the sliding distance of the adjusting rod 601, and the hardness tester impact assembly 502 is further adjusted by the electric push rod 5, so that the impact body impacts the surface of the machine-made sand concrete block under the action of the spring, the coil component measures the impact speed and rebound speed of the impact body, and transmits the measurement signal to the hardness tester host for collection, amplification, processing and operation. Finally, the hardness value of the machine-made sand concrete block is obtained, and is displayed on the display screen. Through the adjustment of the adjusting frame 6 and the adjusting rod 601, the pressing plate 602 can be tightly contacted with the machine-made sand concrete block.

[0031] As the adjusting rod 601 slides, the contact piece 6012 slides along the surface of the access resistor 604, changing the resistance value of the access resistor 604 in the circuit. According to Ohm's law, current is inversely proportional to resistance, so a change in the resistance value of the access resistor 604 will cause a change in the current in the circuit. When the contact pressure of the pressure plate 602 with the manufactured sand concrete block reaches a certain degree, the change in the resistance value of the access resistor 604 causes the current in the circuit to increase to a preset threshold. The current measurement circuit monitors the change in current in the circuit in real time. When the current reaches the preset value, the current measurement circuit sends a trigger signal to the main control box 4. After receiving the signal, the main control box 4 determines that the pressure plate 602 has established stable and reliable contact with the manufactured sand concrete block and that the contact pressure has reached the required conditions for detection. At this time, the main control box 4 controls the electric push rod 5 to stop moving downward and starts the hardness tester impact assembly 502. The hardness tester impact assembly 502 impacts the surface of the manufactured sand concrete block under the action of the spring, and calculates the hardness value of the concrete by measuring the impact speed and rebound speed. This design of the access resistor 604 ensures that the hardness tester impact assembly 502 only starts working after stable contact with the concrete block, thereby avoiding detection errors caused by poor contact or insufficient pressure and improving the accuracy and reliability of the detection results.

[0032] The rear side of the support chassis 1 is provided with a main control box 4, which is made of a solid metal shell and has good protection performance, capable of resisting dust, moisture and electromagnetic interference from the outside. The inside of the main control box 4 is provided with a current measurement circuit and a hardness tester main machine. The current measurement circuit mainly consists of a high-precision current sensor, an operational amplifier, a filter circuit, etc., which can accurately measure the change of current in the circuit and convert the measurement signal into a digital signal for transmission to the hardness tester main machine. The hardness tester main machine collects, amplifies, processes and operates the signals from the hardness tester impact assembly 502, adopts advanced signal processing algorithms and hardness calculation models, and can quickly and accurately obtain the hardness value of the manufactured sand concrete block and display it in real time on the display screen. At the same time, the main control box 4 is also connected with the transmission motor 105, the electric push rod 5, the access resistor 604, etc. through wires, realizing centralized control and coordinated operation of the entire detection device. Under the control of the main control box 4, the transmission motor 105 can start and stop according to the preset program, driving the transmission belt 2 to run stably; the extension and retraction of the electric push rod 5 can also be accurately controlled according to the detection requirements, ensuring that the hardness tester impact assembly 502 and the pressure plate 602 can accurately detect the manufactured sand concrete block; the current measurement signal of the access resistor 604 is used to monitor the contact pressure of the pressure plate 602 with the manufactured sand concrete block in real time, providing feedback control basis for the main control box 4 and ensuring the automation, intelligence and high precision of the entire detection process.

[0033] Workflow: At the beginning, the mechanism sand concrete block to be tested is placed at the starting end of the transmission belt 2. After the operator starts the device, the main control box 4 first controls the electric push rod 5 to drive the connecting frame 501, the hardness tester impact assembly 502 and the pressing plate 602 to move downward. When the pressing plate 602 contacts the concrete block, the strain gauge 603 senses the deformation, the resistance changes, and the signal is fed back to the main control box 4. The access resistance 604 in the adjusting frame 6 measures the sliding distance by current change, and the main control box 4 accurately controls the electric push rod 5 accordingly to ensure that the contact pressure between the pressing plate 602 and the concrete block is stable. After reaching the set pressure, the main control box 4 drives the hardness tester impact assembly 502 to work. The impact body of the impact assembly impacts the surface of the concrete block under the action of the spring force, and the coil measures the impact and rebound speed, and the signal is transmitted to the main control box 4. The main control box 4 collects and processes the signal, uses the hardness calculation model to obtain the concrete hardness value, and presents it through the display screen. After the detection is completed, the electric push rod 5 drives the components to reset, and the operator takes out the tested concrete block. At this time, the main control box 4 starts the transmission motor 105, and the transmission belt 2 runs to convey the next concrete block to be tested to the detection position, and the device enters the next cycle. The whole device integrates transmission, cleaning, pressure regulation and hardness detection functions. The transmission belt 2 is responsible for conveying the concrete block; the elastic support frame 3 and the cleaning brush 7 ensure the cleanliness of the transmission belt 2; the adjusting frame 6 and the strain gauge 603 cooperate with the main control box 4 to accurately control the contact pressure; the hardness tester impact assembly 502 performs hardness detection. Each component works closely to realize automatic operation, improve detection efficiency and accuracy, reduce labor cost, and is suitable for mechanism sand concrete hardness detection, and helps quality control.

[0034] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A mechanism sand concrete hardness detection device, comprising a support chassis (1), characterized in that: The inside of the support chassis (1) is rotatably connected with a driving roller (202) and three driven rollers (203), the outer side walls of the driving roller (202) and the driven rollers (203) are drivingly connected with a transmission belt (2), the front side wall and the rear side wall of the support chassis (1) are fixedly connected with elastic support frames (3), the inside of each elastic support frame (3) is fixedly connected with a guide rod (303), the outer side wall of each guide rod (303) is slidingly connected with a connecting rod (302), the transmission belt (2) is slidingly connected with the inside of the support chassis (1), two connecting rods (302) are fixedly connected with a transmission connecting rod (702), the outer side wall of the transmission connecting rod (702) is fixedly connected with a cleaning brush (7). The upper side wall of the support chassis (1) is fixedly connected with a support top frame (102), the upper side wall of the support top frame (102) is installed with an electric push rod (5), the output end of the electric push rod (5) is fixedly connected with a connecting frame (501), the lower side wall of the connecting frame (501) is installed with a durometer impact assembly (502) in the middle, the lower side wall of the connecting frame (501) is fixedly connected with two adjusting frames (6), the inside of each adjusting frame (6) is slidingly connected with an adjusting rod (601), the lower end of the adjusting rod (601) is fixedly connected with a pressing plate (602), the lower side wall of the pressing plate (602) is fixedly connected with a strain gauge (603). The inside of each elastic support frame (3) is rotatably connected with a rotating rod (301), the rotating rod (301) is rotatably connected with the cleaning brush (7), the rotating rod (301) and the connecting rod (302) are fixedly connected with a transmission rod (3011), the guide rod (303) is arc-shaped, the inside of each connecting rod (302) is provided with a sliding inner groove (3021), the guide rod (303) is matched with the connecting rod (302) through the sliding inner groove (3021), the outer side wall of the guide rod (303) is provided with two supporting springs (3031), the two supporting springs (3031) are respectively located on the two sides of the connecting rod (302), the upper side wall of the cleaning brush (7) is fixedly connected with a brush head (701), the brush head (701) is matched with the lower side wall of the transmission belt (2).

2. The mechanism sand concrete hardness detection device according to claim 1, characterized in that: The rear side wall of the support chassis (1) is fixedly connected with a support rear plate (101), the upper side wall of the support rear plate (101) is installed with a transmission motor (105) and a transmission box (104), the output end of the transmission motor (105) is fixedly connected with the input end of the transmission box (104), the output end of the transmission box (104) is fixedly connected with the driving roller (202).

3. The mechanism sand concrete hardness detection device according to claim 1, characterized in that: The middle part of the outer side wall of the transmission belt (2) is provided with anti-skid lines (201), the inside of the support chassis (1) is fixedly connected with a support plate (103), the upper side wall of the support plate (103) is slidingly connected with the inner side wall of the transmission belt (2).

4. The device for detecting the hardness of machine-made sand concrete according to claim 1, characterized in that: The inner side wall of the adjusting frame (6) is fixedly connected with an access resistor (604), the upper side wall of the adjusting rod (601) is fixedly connected with a connecting strip (6011), one side wall of the connecting strip (6011) close to the access resistor (604) is fixedly connected with a contact piece (6012), one side wall of the contact piece (6012) close to the access resistor (604) is fixedly connected with a graphite sheet, the graphite sheet is in close contact with the access resistor (604), the access resistor (604) is in the shape of an inverted U, and a spring is arranged between the adjusting rod (601) and the upper inner wall of the adjusting frame (6).

5. The machine-made sand concrete hardness detection device according to claim 1, characterized in that: The rear side of the support base frame (1) is provided with a main control box (4), and the inside of the main control box (4) is provided with a current measurement circuit and a hardness tester main machine.

Images