A pipette for asphalt

Abstract

This utility model relates to the technical field of asphalt testing equipment, and provides an asphalt pipette that can achieve controllable quantitative discharge of asphalt under constant temperature conditions, and has a stable structure and strong operational adaptability. It includes: a cylinder for containing asphalt, a handheld outer shell, a heating component, and a pressing dispensing mechanism. The cylinder has a dispensing port at the front end and a detachable cap at the rear end. Heating elements are arranged on the cylinder wall, nozzle, and dispensing port. The pressing dispensing mechanism includes: a push rod, a limiting guide component, a pressing handle, a transmission assembly, a return spring, and a stroke adjustment component. The return spring is normally extended to push the push rod forward, ensuring that the front end of the push rod always blocks the dispensing port. When the pressing handle is applied, the transmission assembly compresses the return spring, causing the push rod to retract backward, thus releasing the blockage of the dispensing port and opening the flow path for asphalt.

Description

Technical Field

[0001] This utility model relates to the technical field of asphalt testing equipment, specifically to a pipette for asphalt. Background Technology

[0002] As a core material in road construction, the accurate testing of asphalt's performance parameters is crucial for ensuring the quality of road engineering projects. In asphalt-related experimental research, such as Marshall stability tests, asphalt mixture mix design, and emulsified asphalt performance characterization, quantitative sampling of asphalt is necessary. Traditional methods require repeatedly heating the entire batch of asphalt, but only a small portion is taken, which easily leads to oxidation and aging, affecting the experimental data. Furthermore, quantitative sampling is usually done by weighing with a balance, which introduces subjective errors and affects the scientific rigor of the experiment.

[0003] Existing pipetting equipment is mostly of a general-purpose, room-temperature design, which has significant limitations in adapting to the high viscosity and low-temperature solidification characteristics of asphalt. On the one hand, general-purpose pipettes lack a full-process temperature control structure, making the asphalt prone to cooling and solidification within the flow channel, clogging the channel and causing quantitative dispensing failures. On the other hand, existing manual pipetting devices lack reliable push rod guidance and rear-end sealing and limiting structures, which can easily lead to push rod misalignment and jamming when dispensing high-viscosity asphalt, asphalt overflow from the rear end, polluting the equipment and the environment, and the flexibility of adjusting the single dispensing volume is insufficient. At the same time, conventional heating structures only cover the storage chamber section, and the temperature at the front outlet is insufficient, making secondary solidification easy to occur.

[0004] Therefore, developing a dedicated asphalt pipette that integrates full-channel constant temperature heating, adjustable press-to-dispense, and anti-overflow limiting and guiding functions is of great engineering significance for improving the ease of operation, accuracy of dispensing, and long-term operational reliability of asphalt testing. Utility Model Content

[0005] The purpose of this invention is to overcome the defects of the existing technology and provide a pipette for asphalt that can achieve controllable quantitative discharge of asphalt under constant temperature conditions, and has a stable structure and strong operational adaptability.

[0006] The objective of this utility model is achieved through the following technical solution: A pipette for asphalt includes: a cylinder for containing asphalt, a handheld casing, a heating assembly, and a dispensing mechanism. A cap is detachably connected to the rear end of the cylinder, and a nozzle is provided at the front end of the cylinder. The free end of the nozzle is configured as the dispensing port of the asphalt pipette. The handheld casing is disposed at the nozzle, and its front end is connected to the end of the nozzle furthest from the dispensing port. The heating assembly includes: a non-metallic retaining ring, a power supply wire, and heating elements disposed on the cylinder wall, the nozzle, and the dispensing port. A wiring channel is provided inside the non-metallic retaining ring for the power supply wire to pass through, and the power supply wire is electrically connected to the heating element via the wiring channel of the non-metallic retaining ring. The press-to-dispense mechanism includes: a push rod, a limiting guide assembly, a press handle, a transmission engagement assembly, a return spring, and a stroke adjustment assembly. The limiting guide assembly is located at the junction of the nozzle and the handheld housing. The limiting guide assembly has a radial through hole. The front end of the push rod passes through the radial through hole of the limiting guide assembly and enters the nozzle, and the push rod can move axially back and forth. When the front end of the push rod moves to the outlet, the front end of the push rod fits against the inner wall of the outlet to form a releasable sealing fit. The press handle is hinged to the handheld housing and is driven to the rear end of the push rod through the transmission engagement assembly. The return spring is sleeved on the push rod, and its two ends abut against the transmission engagement assembly and the rear end of the handheld housing, respectively. The stroke adjustment assembly is located at the rear end of the handheld housing to limit the maximum swing amplitude of the press handle, thereby adjusting the maximum axial advance stroke of the push rod.

[0007] The return spring is in an extended state under normal conditions to push the push rod forward, so that the front end of the push rod always blocks the liquid outlet under normal conditions; when the handle is pressed, the transmission assembly compresses the return spring, thereby driving the push rod to retract backward, so that the push rod releases the blockage of the liquid outlet.

[0008] Preferably, the limiting guide assembly is at least one set of guide sealing rings fixedly installed on the inner wall of the nozzle, and the push rod passes through the guide sealing ring and forms a sliding sealing fit with it, thereby realizing radial limiting of the front end of the push rod and preventing overflow sealing of asphalt.

[0009] Preferably, the heating element is a heating resistance wire that is continuously or segmentally wound along the cylinder wall, the outer wall of the nozzle, and the outer periphery of the liquid outlet, so as to achieve synchronous heat preservation and heating throughout the entire asphalt flow path.

[0010] Preferably, the non-metallic retaining ring is made of heat-insulating non-metallic material, the wiring channel is sealed and connected to the heating element and the power supply wiring, and the non-metallic retaining ring can also serve as a hand grip during operation, preventing the heat from the heating end from being conducted backward.

[0011] Preferably, the non-metallic fixing ring can also be made of high-temperature resistant, high-strength, heat-insulating polymer material. The wiring channel is sealed and connected to the heating element and the power supply wiring, and has the triple functions of fixing the wiring, electrical insulation, and holding and heat insulation.

[0012] Preferably, the stroke adjustment component is a threaded rotary limit knob, which changes its length inside the hand-held housing by turning it to limit the maximum downward stroke of the pressing handle, thereby controlling the volume of asphalt discharged in a single operation.

[0013] Preferably, the inner wall of the outlet is provided with a low-viscosity, smooth, polished coating to reduce the adhesion and residue of viscous asphalt and ensure the accuracy of quantitative discharge.

[0014] The asphalt pipette proposed in this utility model has the following advantages compared with the prior art: 1. The front end of the push rod acts as a sealing valve core to normally block the liquid outlet. Pressing it opens the flow channel, and releasing it automatically stops the liquid flow. The operation is effortless and intuitive.

[0015] 2. The maximum retraction stroke of the push rod can be flexibly adjusted according to the test requirements to control the opening degree of the liquid outlet, stabilize the single liquid output, and adapt to the sampling requirements of different tests.

[0016] 3. The cylinder has a built-in limiting and guiding component, which not only restrains the radial deviation of the push rod during movement and avoids jamming, but also prevents high-viscosity asphalt from overflowing backward through the sealing structure, adapting to the material characteristics of high-viscosity asphalt and ensuring a clean test environment.

[0017] 4. The heating layout covering the entire flow channel, combined with a multi-functional non-metallic fixing ring, maintains the temperature required for asphalt flow throughout the process, completely solving the problem of asphalt solidification and pipe blockage. At the same time, the heat insulation structure can prevent burns during operation and protect the electrical components at the back end.

[0018] 5. The overall structure is highly integrated, with the heating circuit built-in and hidden. The rear end of the cylinder can be opened for cleaning and maintenance, making it suitable for most indoor asphalt testing scenarios such as Marshall test and emulsified asphalt testing. Attached Figure Description

[0019] Figure 1 is a three-dimensional structural schematic diagram of a preferred embodiment of the pipette for asphalt according to the present invention.

[0020] Figure 2 is Figure 1The axial cross-sectional view of the embodiment shown illustrates the internal structure of the cylinder, handheld housing, and press-to-dispense mechanism.

[0021] Figure 3 is Figure 1 The schematic diagram of the press-to-dispense mechanism in the embodiment shown is shown.

[0022] The diagram shows the structure corresponding to the labels: 101 - Cylinder (asphalt storage cylinder); 102 - Cylinder cover; 103 - Cylinder nozzle; 104 - Liquid outlet; 105 - Non-metallic retaining ring; 106 - Handheld casing; 107 - Power connection; 108 - Heating element; 2 - Press-to-dispense mechanism; 201 - Push rod; 202 - Limit guide assembly; 203 - Press handle; 204 - Transmission assembly; 205 - Return spring; 206 - Stroke adjustment assembly. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments. However, the embodiments are not intended to limit the present invention. Any similar structures and similar variations of the present invention should be included in the protection scope of the present invention.

[0024] Overall assembly Combination Figure 1 and Figure 2 The illustrated asphalt pipette includes: a cylinder 101 for containing asphalt, a handheld casing 106, a heating element, and a pressing dispensing mechanism 2. The rear end of the cylinder 101 is open, and a cap 102 is detachably fitted to it via a threaded or snap-fit ​​structure, facilitating asphalt filling and internal cleaning and maintenance. The front end of the cylinder 101 narrows to form a conical nozzle 103, and the end of the nozzle 103 has an opening forming the asphalt pipette outlet 104, thus creating a complete flow channel for asphalt entry and exit. The inner wall of the outlet 104 is coated with a low-viscosity, smooth, polished coating to reduce the adhesion and residue of viscous asphalt, ensuring accurate dispensing. The front end of the handheld casing 106 is connected to the end of the nozzle 103 furthest from the outlet 104.

[0025] Combination Figure 3As shown, the press-to-dispense mechanism 2 includes: a push rod 201, a limiting guide assembly 202, a press handle 203, a transmission engagement assembly 204, a return spring 205, and a stroke adjustment assembly 206. The limiting guide assembly 202 is located at the junction of the nozzle 103 and the handheld housing 106. The limiting guide assembly 202 has a radial through hole, through which the front end of the push rod 201 enters the nozzle 103, and the push rod 201 can move axially back and forth. When the front end of the push rod 201 moves to the outlet 104, it fits against the inner wall of the outlet 104 to form a releasable sealing fit. The press handle 203 is hinged to the handheld housing 106 and is connected to the rear end of the push rod 201 via the transmission engagement assembly 204. The return spring 205 is sleeved on the push rod 201, with its two ends abutting between the transmission engagement assembly 204 and the rear end of the handheld housing 106. The stroke adjustment component 206 is located at the rear end of the handheld housing 106 to limit the maximum swing amplitude of the pressing handle 203, so as to adjust the maximum axial push stroke of the push rod 201.

[0026] The heating assembly includes a non-metallic retaining ring 105, a power supply wiring 107, and a heating element 108. The heating element 108 is arranged on the cylinder wall, nozzle 103, and liquid outlet 104 of the cylinder body 101. The non-metallic retaining ring 105 has a wiring channel inside for the power supply line to pass through. The power supply wiring 107 is electrically connected to the heating element 108 through the wiring channel in the non-metallic retaining ring 105.

[0027] Operation-driven logic The return spring 205 is normally extended to push the push rod 201 forward, ensuring that the front end of the push rod 201 always blocks the outlet 104. When the handle 203 is pressed, the handle 203 is subjected to force, and the transmission assembly 204 compresses the return spring 205, thereby causing the push rod 201 to retract backward. This releases the blockage of the outlet 104 by the push rod 201, opening the flow channel for asphalt in and out. The liquid asphalt in the cylinder 101 is then stably discharged from the outlet 104 through the opened flow channel under its own weight. After the handle is released, the return spring 205 rebounds, pushing the transmission assembly 204, causing the push rod 201 to return to its original position. The front end of the push rod 201 then re-closes and blocks the outlet 104, immediately stopping the discharge. The stroke adjustment assembly 206 can limit the maximum swing amplitude of the handle 203, thereby adjusting the stroke of the push rod 201 and controlling the amount of asphalt discharged per cycle. The stroke adjustment component 206 preferably adopts a threaded rotary limit knob, which limits the maximum downward stroke of the pressing handle 203 by changing its length extending into the handheld housing.

[0028] Limit seal The limiting and guiding assembly 202 is located at the junction of the nozzle 103 and the handheld housing 106. It can be at least one set of guide sealing rings fixedly installed on the inner wall of the nozzle 103, preferably two sets of guide sealing rings arranged axially at intervals. The push rod 201 passes through the guide sealing rings and forms a sliding seal with them. On the one hand, it forms a radial limiting constraint on the front end of the push rod to prevent the push rod from swaying or getting stuck when pushing high-viscosity asphalt; on the other hand, it forms an axial sealing barrier to prevent asphalt from overflowing and flowing backward along the push rod gap under static pressure, protecting the rear transmission structure and maintaining a clean test environment.

[0029] Constant temperature heating The heating element can be a heating resistance wire, which is continuously wound and arranged along the entire wall of the cylinder 101, the wall of the nozzle 103, and the outer periphery of the liquid outlet 104. Figure 2 The structure shown in the cross-section (indicated by small circles) provides simultaneous heating and insulation for the asphalt throughout its entire path from storage to discharge, eliminating the risk of localized cooling and solidification. The non-metallic fixing ring 105 is made of high-temperature resistant material, with a pre-reserved through-wiring channel inside. After the power supply wiring 107 is connected, it passes through the channel and completes the electrical connection with the heating elements 108 at various locations. The design of the non-metallic fixing ring 105, while neatly fixing the power supply line, relies on its own heat insulation performance to block the heat transfer from the heating section to the rear, thus preventing burns to the operator and protecting the rear handle and electrical components from high-temperature aging.

[0030] The entire set of components works together to form a complete asphalt transfer structure that integrates material storage, quantity control, spill prevention, and constant temperature heating. Actual usage process: 1. Connect the power supply (107) to an external temperature control power supply and preheat the entire flow channel to the set temperature suitable for asphalt flow (130~150℃ for conventional road asphalt); 2. Unscrew the cap (102) at the rear end of the cylinder and inject the preheated liquid asphalt into the cylinder (101). After filling, tighten the cap; 3. Align the outlet with the target container, press the handle to squeeze out the metered amount of asphalt, and open the flow channel to discharge the metered amount of asphalt; after releasing the handle, the flow channel is blocked, and the liquid discharge stops; the limit guide component throughout the process maintains the smooth movement of the push rod, and the heating of the entire flow channel ensures the fluidity of the asphalt, and there will be no problems of pipe blockage or leakage in the middle.

[0031] The above description is merely a description of a preferred embodiment of the present utility model and is not intended to limit the scope of the present utility model in any way. Any changes or modifications made by those skilled in the art based on the above-disclosed technical content should be considered as equivalent and valid embodiments and fall within the protection scope of the present utility model.

Claims

1. A pipette for bitumen, characterized in that include: The cylinder (101) for containing asphalt, the handheld casing (106), the heating assembly, and the pressing dispensing mechanism (2) are used. The rear end of the cylinder (101) is detachably connected to a cap (102), and the front end of the cylinder (101) is provided with a nozzle (103). The free end of the nozzle (103) is configured as the outlet (104) of the asphalt pipette. The handheld housing (106) is disposed at the nozzle (103), and the front end of the handheld housing (106) is connected to the end of the nozzle (103) away from the liquid outlet (104); The heating assembly includes: a non-metallic retaining ring (105), a power supply wiring (107), and heating elements (108) disposed on the cylinder wall of the cylinder body (101), the cylinder nozzle (103), and the liquid outlet (104). The non-metallic retaining ring (105) has a wiring channel inside for the power supply line to pass through. The power supply wiring (107) is electrically connected to the heating element (108) through the wiring channel of the non-metallic retaining ring (105). The press-to-dispense mechanism (2) includes: a push rod (201), a limiting guide assembly (202), a press handle (203), a transmission engagement assembly (204), a return spring (205), and a stroke adjustment assembly (206). The limiting guide assembly (202) is located at the junction of the nozzle (103) and the handheld housing (106). The limiting guide assembly (202) has a radial through hole. The front end of the push rod (201) passes through the radial through hole of the limiting guide assembly (202) and enters the nozzle (103). The push rod (201) can move back and forth axially. When the front end of the push rod (201) moves to the position of the liquid outlet (104), the push rod (201)... The front end of 01) is fitted with the inner wall of the liquid outlet (104) to form a releasable sealing and plugging fit. The pressing handle (203) is hinged to the hand-held shell (106) and is connected to the rear end of the push rod (201) through the transmission fit assembly (204). The return spring (205) is sleeved on the push rod (201). The two ends of the return spring (205) respectively abut against the rear end of the transmission fit assembly (204) and the hand-held shell (106). The stroke adjustment assembly (206) is located at the rear end of the hand-held shell (106) to limit the maximum swing amplitude of the pressing handle (203) so as to adjust the maximum axial push stroke of the push rod (201). The return spring (205) is in an extended state under normal conditions to push the push rod (201) forward, so that the front end of the push rod (201) always blocks the liquid outlet (104) under normal conditions. When the handle (203) is pressed, the transmission assembly (204) compresses the return spring (205), thereby causing the push rod (201) to retract backward, so that the blockage of the liquid outlet (104) by the push rod (201) is released.

2. A pipette for asphalt according to claim 1, characterized in that: The limiting guide assembly (202) is at least one set of guide sealing rings fixedly installed on the inner wall of the nozzle (103), and the push rod (201) passes through the guide sealing rings and forms a sliding sealing fit with them.

3. A pipette for asphalt according to claim 1, characterized in that: The heating element (108) is a heating resistance wire that is continuously or segmentally wound along the outer wall of the cylinder (101), the outer wall of the nozzle (103), and the outer periphery of the liquid outlet (104).

4. The pipette for asphalt according to claim 1, characterized in that: The non-metallic retaining ring (105) is made of heat-insulating non-metallic material, and the wiring channel is sealed and connected to the heating element (108) and the power supply wiring (107).

5. A pipette for asphalt according to claim 1, characterized in that: The non-metallic fixing ring (105) is made of high temperature and high strength heat-insulating polymer material, and the wiring channel is sealed and connected to the heating element (108) and the power supply wiring (107).

6. A pipette for asphalt according to claim 1, characterized in that: The stroke adjustment component (206) is a threaded rotary limit knob.

7. A pipette for asphalt according to claim 1, characterized in that: The inner wall of the liquid outlet (104) is provided with a low-viscosity, smooth, polished coating.

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