Automatic asphalt penetrometer

Abstract

The utility model relates to an automatic pitch penetration apparatus, including base, the upper end of base is equipped with support and is used to place the liftable platform of sample dish, and the base has the cavity of accommodating liftable platform, be provided with lifting assembly on the support, and the bottom of movable end of lifting assembly installs needle control assembly, and the standard needle is installed on needle control assembly, the bottom of fixed end of lifting assembly installs lifting arm, the coaxial sleeve of one center bearing is equipped with in the lower end of lifting arm, and one cross arm is sleeved in the outer ring of center bearing, the utility model drives the measuring rod coarse adjustment through the lifting arm, and then through the locking rod microdistance locking, and the pitch surface measuring piece can be accurate zero mark with the light touch sample surface, and then the measuring rod rotates 180 DEG, and the standard needle calibration piece that replaces the original position with the standard needle coplanar with the measuring piece, and the standard needle only needs to be perpendicular to drop and abut the calibration piece, and the zero distance setting of needle point and pitch surface is completed, thereby significantly reduces the artificial error, improves the test repeatability and operation efficiency.

Description

Technical Field

[0001] This utility model relates to asphalt penetration testing, and more particularly to an automatic asphalt penetration tester. Background Technology

[0002] Penetration is one of the core indicators for evaluating asphalt performance. It characterizes the asphalt's hardness, consistency, and resistance to shear failure. Specifically, it measures the depth (in units of 0.1 mm) to which a standard conical needle penetrates a standard asphalt sample vertically under a specified temperature (typically 25°C) and a specified load (typically 100 g). This indicator directly affects the workability and durability of asphalt in practical engineering projects.

[0003] However, existing penetration testing devices require manual alignment of the standard needle precisely with the asphalt sample surface before testing. This process is highly dependent on the operator's experience, and a slight mistake can cause the needle to be inserted into the asphalt prematurely during the positioning stage, resulting in a shift in the initial reference point and thus causing a large error in the test results.

[0004] Therefore, there is an urgent need for an asphalt penetration test device that can accurately achieve zero-contact positioning between the needle and the sample surface to improve test accuracy and ease of operation. Utility Model Content

[0005] To address the problem in existing technologies where the asphalt penetration test requires aligning the needle with the asphalt surface beforehand, and the needle may easily insert directly into the asphalt during descent, this invention provides an automatic asphalt penetration tester.

[0006] The technical solution is as follows: An automatic asphalt needle penetration meter includes a base, the upper end of which is provided with a bracket and a liftable platform for placing a sample dish. The base has a cavity to accommodate the liftable platform. A lifting assembly is provided on the bracket. A needle control assembly is installed at the bottom of the movable end of the lifting assembly. A standard needle is installed on the needle control assembly. A lifting arm is installed at the bottom of the fixed end of the lifting assembly. A central bearing is coaxially sleeved at the lower end of the lifting arm. A cross arm is sleeved on the outer ring of the central bearing. A measuring rod is installed on the cross arm. The two ends of the measuring rod are slidably connected to the two ends of the cross arm. A locking rod is provided at one end of the cross arm to fix the measuring rod on the cross arm. An asphalt surface measuring piece is installed at the end of the measuring rod near the locking rod. A standard needle calibration piece is installed at the other end of the measuring rod. The upper end face of the standard needle calibration piece is at the same height as the lower end face of the asphalt surface measuring piece.

[0007] Optionally, the measuring rod includes a horizontal portion and vertical portions respectively connected to both ends of the horizontal portion, the middle part of the horizontal portion being curved into a semi-circular ring and surrounding the side of the lifting arm.

[0008] Optionally, the vertical portion of the measuring rod is equipped with a vertical slide rail, and the horizontal arm is equipped with a vertical slider that cooperates with the vertical slide rail.

[0009] Optionally, the lifting arm includes an inner tube and an outer tube slidably sleeved on the inner tube. The upper end of the outer tube is fixed to the bottom of the fixed end of the lifting assembly via a flange. A vertical lead screw is coaxially arranged inside the outer tube. The upper end of the vertical lead screw is connected to the inner wall of the outer tube via a bearing. A pair of meshing helical gears are installed on the upper end of the vertical lead screw. A crank handle is provided on one of the helical gears. One end of the crank handle is rotatably connected to the outer tube, and the other end is a hand-held end that extends outward from the outer tube. A vertical lead screw nut is fitted on the vertical lead screw. The outer wall of the vertical lead screw nut is fixed to the inner wall of the inner tube via a bearing. The crank handle drives the vertical lead screw to rotate, causing the vertical lead screw nut to drive the inner tube to extend and retract along the outer tube.

[0010] Optionally, the liftable platform includes a base frame and a shelf. The base frame is installed at the bottom of the cavity of the base, and a guide rail pair and a lead screw module are provided on the base frame. The lead screw module includes a horizontal lead screw, a drive motor, and two horizontal lead screw nuts assembled on the lead screw. The horizontal lead screw is installed on the base frame and is connected to the drive motor for transmission. The horizontal lead screw has two sections of threads with opposite directions of rotation, and the two horizontal lead screw nuts are respectively assembled on the two sections of threads. The guide rail pair includes a horizontal guide rail and two horizontal sliders arranged on the horizontal guide rail. Each of the two horizontal sliders is provided with an inclined block. The two inclined blocks are symmetrically arranged, and the side closest to each other is an inclined surface. The two inclined blocks are connected to the two horizontal sliders one-to-one. It also includes a tension spring. One end of the tension spring is connected to the base frame, and the other end is connected to the bottom of the shelf. The upper end of the base has an opening that allows the shelf to extend out, and the shelf rests on the upper end of the inclined block.

[0011] Optionally, the bottom of the shelf is provided with symmetrically arranged abutment wheels, the lower end of which abuts against the upper end of the inclined block.

[0012] Optionally, the cavity of the base is provided with a partition plate for separating the liftable platform from the electrical components.

[0013] The beneficial effects of this utility model are:

[0014] 1. This utility model uses a lifting arm to drive the measuring rod for coarse adjustment, and then uses a locking rod for fine locking, so that the asphalt surface measuring piece can be accurately zeroed by lightly touching the sample surface. Then the measuring rod is rotated 180°, and a standard needle calibration piece coplanar with the measuring piece replaces the original position. The standard needle only needs to descend vertically to contact the calibration piece to complete the zero distance setting between the needle tip and the asphalt surface, thereby significantly reducing human error and improving test repeatability and work efficiency.

[0015] 2. By designing the horizontal part of the measuring rod as a semi-circular ring that surrounds the lifting arm, this utility model allows the measuring plate and the calibration plate to rotate synchronously around the needle without increasing the lateral dimension, resulting in more compact positioning and avoiding interference.

[0016] 3. The vertical slide rail and the vertical slider of this utility model cooperate to make the two ends of the measuring rod rise and fall synchronously and smoothly without shaking, and the zero position is kept accurate after locking.

[0017] 4. This utility model uses a crank handle, helical gear, and vertical lead screw to drive the inner tube to extend and retract, achieving precise micro-adjustment and quick, labor-saving positioning.

[0018] 5. This utility model utilizes a bidirectional lead screw to drive two inclined blocks to open and close synchronously. The shelf rises and falls smoothly under the dual action of the inclined plane and the tension spring, and the sample dish enters and exits the cavity smoothly, making the operation smooth and efficient.

[0019] 6. This utility model adds abutment wheels to the bottom of the shelf, changing sliding to rolling, which reduces lifting resistance and avoids wear on the inclined blocks, maintaining synchronization accuracy over a long period of time. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0021] Figure 2 This is a partial structural schematic diagram of the present invention.

[0022] Figure 3 This is a longitudinal sectional view of the lifting arm of this utility model.

[0023] Figure 4 This is a cross-sectional view of the base of this utility model.

[0024] Figure 5 This is a structural schematic diagram of the lifting platform of this utility model.

[0025] Explanation of reference numerals in the attached diagram: 1_base, 11_notch, 2_liftable platform, 21_base frame, 22_shelf, 221_abutment wheel, 231_horizontal guide rail, 232_horizontal slider, 241_horizontal lead screw, 242_drive motor, 243_horizontal lead screw nut, 25_wedge block, 26_tension spring, 3_lifting assembly, 31_moving end, 32_fixed end, 4_needle control assembly, 41_standard needle, 5_lifting arm. 51_Inner tube, 52_Outer tube, 53_Vertical lead screw, 541, 542_Helical gear, 55_Handle, 56_Vertical lead screw nut, 61_Central bearing, 62_Horizontal arm, 63_Measuring rod, 631_Horizontal part, 632_Vertical part, 64_Locking rod, 65_Asphalt surface measuring piece, 66_Standard needle calibration piece, 67_Vertical slide rail, 68_Vertical slider, 7_Bracket, 8_Sample dish, 9_Isolation plate. Detailed Implementation

[0026] The following description is only a preferred embodiment of the present invention and does not limit the scope of protection of the present invention.

[0027] like Figure 1-5 The automatic asphalt penetration tester shown includes a base 1, with a support 7 fixed at the upper end of the base 1. The base 1 has an open cavity inside, and a liftable platform 2 is installed in the cavity to support the sample dish 8. A lifting assembly 3 is fixed at the top of the support 7. The fixed end 32 of the lifting assembly 3 is locked to the support 7 by a flange, and its movable end 31 can reciprocate in the vertical direction. A needle control assembly 4 is installed on the lower surface of the movable end 31. The needle control assembly 4 can clamp and release a standard needle 41 to perform a standard needle penetration test.

[0028] For details, please refer to the following: Figure 3 To avoid errors caused by traditional manual alignment, this embodiment adds a lifting arm 5 to the bottom of the fixed end 32. The lifting arm 5 consists of an outer tube 52 and an inner tube 51. The upper end of the outer tube 52 is connected to the flange of the fixed end 32, and a vertical lead screw 53 is coaxially arranged inside. The top end of the vertical lead screw 53 is fixed to the inner wall of the outer tube 52 by a bearing, and is driven by a crank handle 55 through helical gears 541 and 542. In this embodiment, the helical gear 541 is connected to the vertical lead screw 53, and the crank handle 55 is connected to the helical gear 542. When the crank handle 55 is turned, the vertical lead screw 53 rotates, driving the vertical lead screw nut 56 to move axially. The vertical lead screw nut 56 is fixed to the inner tube 51 through the bearing, thereby driving the inner tube 51 to extend and retract relative to the outer tube 52, realizing precise fine adjustment.

[0029] For details, please refer to the following: Figure 2 The lower end of the inner tube 51 is rotatably connected to the horizontal arm 62 via a central bearing 61. Vertical sliders 68 are symmetrically arranged at both ends of the horizontal arm 62. The middle of the horizontal portion 631 of the measuring rod 63 forms a semi-circular ring around the lifting arm 5, with both ends extending downwards to form vertical portions 632. Vertical slide rails 67 are installed on the vertical portions 632, cooperating with the vertical sliders 68 to allow the measuring rod 63 to slide up and down relative to the horizontal arm 62. A locking rod 64 is also provided at one end of the horizontal arm 62, which can lock the measuring rod 63 at any height. By setting the vertical slide rails 67 and the vertical sliders 68, the two vertical portions 632 can remain synchronized and not tilted, thus maintaining a consistent end height.

[0030] Furthermore, an asphalt surface measuring piece 65 is installed at one end of the measuring rod 63, and a standard needle calibration piece 66 is installed at the other end, with the measuring reference surfaces of the two pieces being strictly coplanar. In one specific embodiment, the upper end face of the standard needle calibration piece 66 and the lower end face of the asphalt surface measuring piece 65 are at the same height. In actual operation, the lifting arm 5 is first driven to make the asphalt surface measuring piece 65 lightly touch the asphalt surface, and the locking rod 64 is locked; then the horizontal arm 62 is rotated 180° around the central bearing 61 so that the standard needle calibration piece 66 is located directly below the standard needle 41, and the lifting assembly 3 is lowered slightly again until the needle tip just touches the calibration piece 66. At this time, the needle tip and the asphalt surface are at the theoretical zero distance. The entire alignment process does not require manual visual inspection, and the error can be controlled within approximately 0.02mm.

[0031] refer to Figure 1 , Figure 4 and Figure 5 To facilitate the handling of the sample dish 8 and to prevent interference when rotating the horizontal arm 62, the lifting platform 2 adopts a scissor-type inclined block structure. Its base frame 21 is fixed to the bottom of the cavity, and a horizontal guide rail 231 and a horizontal lead screw 241 are arranged in parallel on it. The horizontal lead screw 241 is driven by a drive motor 242. The horizontal lead screw 241 has two sections of threads with opposite directions, which respectively cooperate with two horizontal lead screw nuts 243. A horizontal slider 232 is fixed on each of the two horizontal lead screw nuts 243. An inclined block 25 is installed on the top of each horizontal slider 232, and the two inclined blocks 25 are symmetrically distributed. Furthermore, four corner abutment wheels 221 are installed at the bottom of the shelf 22. The abutment wheels 221 roll in contact with the inclined surfaces of the inclined blocks 25. When the drive motor 242 rotates, the two inclined blocks 25 move synchronously in opposite directions, so that the shelf 22 can be raised and lowered smoothly in the vertical direction. One end of the tension spring 26 is connected to the base frame 21 and the other end is connected to the shelf 22. It is used to provide downward restoring force to prevent the shelf 22 from floating when unloaded. The notch 11 of the base 1 allows the shelf 22 to be raised to be flush with the upper surface of the base 1, which is convenient for the operator to take out and put in the sample dish 8.

[0032] In addition, it should be noted that the inclined block 25 has two horizontal planes and one inclined plane. The upper end of the inclined plane is smoothly connected to the top horizontal plane, and the lower end is smoothly connected to the bottom horizontal plane. When the abutment wheel 221 of the shelf 22 moves to the two horizontal planes, even if the inclined block 25 continues to move, the height of the shelf 22 remains unchanged. In this way, the highest and lowest positions of the shelf 22 are unique and will not affect the measurement.

[0033] In addition, refer to Figure 4 An isolation plate 9 is welded inside the cavity of the base 1 to isolate the lifting platform 2 from electrical components, preventing interference between the lifting platform 2 and the circuit, thereby improving the overall lifespan and safety of the machine.

[0034] This embodiment achieves automatic alignment of the standard needle with the asphalt surface with zero contact through the above structure, avoiding misinsertion before the test and greatly improving test efficiency and repeatability.

[0035] The embodiments described above are merely preferred embodiments of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications, improvements, and substitutions without departing from the inventive concept, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. An automatic asphalt penetration tester, characterized in that, Includes a base (1), the upper end of which is provided with a bracket (7) and a liftable platform (2) for placing a sample dish (8). The base (1) has a cavity to accommodate the liftable platform (2). A lifting component (3) is provided on the bracket (7). A needle control component (4) is installed at the bottom of the movable end (31) of the lifting component (3). A standard needle (41) is installed on the needle control component (4). A lifting arm (5) is installed at the bottom of the fixed end (32) of the lifting assembly (3). A central bearing (61) is coaxially sleeved at the lower end of the lifting arm (5). A cross arm (62) is sleeved on the outer ring of the central bearing (61). A measuring rod (63) is installed on the cross arm (62). The two ends of the measuring rod (63) are slidably connected to the two ends of the cross arm (62). A locking rod (64) is provided at one end of the cross arm (62) to fix the measuring rod (63) on the cross arm (62). An asphalt surface measuring piece (65) is installed at one end of the measuring rod (63) near the locking rod (64). A standard needle calibration piece (66) is installed at the other end of the measuring rod (63). The upper end face of the standard needle calibration piece (66) is at the same height as the lower end face of the asphalt surface measuring piece (65).

2. The automatic asphalt penetration tester according to claim 1, characterized in that, The measuring rod (63) includes a horizontal part (631) and vertical parts (632) respectively connected to both ends of the horizontal part (631). The middle part of the horizontal part (631) is curved into a semi-circular ring and surrounds the side of the lifting arm (5).

3. The automatic asphalt penetration tester according to claim 2, characterized in that, The vertical portion (632) of the measuring rod (63) is equipped with a vertical slide rail (67), and the horizontal arm (62) is equipped with a vertical slider (68) that is compatible with the vertical slide rail (67).

4. The automatic asphalt penetration tester according to claim 1, characterized in that, The lifting arm (5) includes an inner tube (51) and an outer tube (52) slidably sleeved on the inner tube (51). The upper end of the outer tube (52) is fixed to the bottom of the fixed end (32) of the lifting assembly (3) by a flange. A vertical lead screw (53) is coaxially arranged inside the outer tube (52). The upper end of the vertical lead screw (53) is connected to the inner wall of the outer tube (52) by a bearing. A pair of meshing helical gears (541, 542) are also installed at the upper end of the vertical lead screw (53). A crank handle (55) is provided on the gears (541, 542). One end of the crank handle (55) is rotatably connected to the outer tube (52), and the other end is a hand-held end that extends outward from the outer tube (52). A vertical screw nut (56) is mounted on the vertical screw rod (53). The outer wall of the vertical screw nut (56) is fixed to the inner wall of the inner tube (51) through a bearing. The crank handle (55) drives the vertical screw rod (53) to rotate, so that the vertical screw nut (56) drives the inner tube (51) to extend and retract along the outer tube (52).

5. The automatic asphalt penetration tester according to claim 1, characterized in that, The liftable platform (2) includes a base frame (21) and a shelf (22). The base frame (21) is installed at the bottom of the cavity of the base (1). The base frame (21) is provided with a guide rail pair and a lead screw module. The lead screw module includes a horizontal lead screw (241), a drive motor (242), and two horizontal lead screw nuts (243) assembled on the horizontal lead screw (241). The horizontal lead screw (241) is mounted on the base frame (21) and is connected to the drive motor (242) for transmission. The horizontal lead screw (241) has two sections of threads with opposite directions of rotation. The two horizontal lead screw nuts (243) are respectively assembled on the two sections of threads. The guide rail pair includes a horizontal guide rail (231) and two horizontal sliders (232) disposed on the horizontal guide rail (231). Each of the two horizontal sliders (232) is provided with an inclined block (25). The two inclined blocks (25) are symmetrically arranged, and the side that is close to each other is an inclined surface. The two inclined blocks (25) are connected to the two horizontal sliders (232) in a one-to-one correspondence. It also includes a tension spring (26), one end of which is connected to the base frame (21) and the other end is connected to the bottom of the shelf (22). The upper end of the base (1) is provided with a notch (11) that allows the shelf (22) to extend out. The shelf (22) is placed on the upper end of the inclined block (25).

6. The automatic asphalt penetration tester according to claim 5, characterized in that, The bottom of the shelf (22) is provided with symmetrically arranged abutment wheels (221), and the lower end of the abutment wheels (221) abuts against the upper end of the inclined block (25).

7. The automatic asphalt penetration tester according to claim 5, characterized in that, The cavity of the base (1) is provided with a partition plate (9) for separating the liftable platform (2) from the electrical components.

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