A three-dimensional detection device for bottle and pipe fittings

Abstract

The present invention discloses a three-dimensional detection device for bottle tube fittings. It relates to the field of thickness measurement, and includes a workbench, on which a fixing component is arranged, and the fixing component can fix the bottle tube fittings; a first detection component, including a first detection probe and a first transmission mechanism, and the first transmission mechanism can drive the first detection probe to move in a vertical direction; a clamping component, which is slidably mounted on a fixed rod, and the clamping component includes a clamping claw, and the clamping claw is used to clamp the bottle tube fittings; a second detection component, including a second detection probe and a second transmission mechanism, and the second transmission mechanism can drive the second detection probe to reciprocate in a horizontal direction toward the center of the fixing component; a third detection component, including a third detection probe and a third transmission mechanism, and the third transmission mechanism can drive the third detection probe to move in a vertical direction. The present invention can realize accurate detection of bottle tube-like components, with high detection efficiency, and can realize three-dimensional detection of bottle tube-like components.

Description

Technical Field

[0001] The invention relates to the field of thickness measurement, and in particular to a three-dimensional detection device for bottle tube fittings. Background Art

[0002] With the rapid development of manufacturing technology, the requirements for bottle tube components are getting higher and higher. At the same time, due to the requirement for lightweight, there are extremely high requirements for the wall thickness of bottle tube components. Therefore, in the production process, it is necessary to test the wall thickness of bottle tube components.

[0003] The journal "China Metrology", written by Han Huagang and others, entitled "Design of intelligent caliper for measuring the extreme value of outer diameter and ovality of steel pipes", disclosed a measurement scheme for the outer diameter and ovality of steel pipes using an intelligent caliper.

[0004] CN116678359A discloses a method and device for detecting the bottom of a tube bottle. The technical solution includes driving the tube bottle to rotate around its axis, and controlling the rotating tube bottle to move relative to a detection mechanism arranged on one side of the bottom of the tube bottle, so that the detection mechanism forms a plurality of detection points distributed in a spiral on the bottom of the tube bottle, and then determining the thickness and / or concave-convex information of the bottom of the tube bottle according to the distance between the plurality of detection points and the detection mechanism. However, the technical solution has complicated detection steps and low detection efficiency, and requires multiple spot checks on the tube bottle to be detected, wasting a lot of time.

[0005] CN212158526U discloses a device for conveniently measuring the thickness of the bottom of a tube glass bottle. The technical solution includes a base with a cavity arranged inside, a column arranged on the base, a cross bar hinged on the column, a digital dial indicator arranged on the cross bar, and a plurality of lower contacts arranged below the digital dial indicator. The lower contacts are arranged on a turntable, which is arranged on the base. A driving device is connected to the turntable through a transmission device. The driving device and the cross bar are connected through a transmission device. The transmission device includes a vertically arranged driving rod, a guide sleeve is arranged on the driving rod, the guide sleeve is installed on the base, a connecting rod is hinged on the driving rod, one end of the connecting rod is hinged with the cross bar, a bar tooth is installed on the driving rod, a second gear is meshed on the bar tooth, the second gear passes through two support rods, the two support rods are installed on the base, a first gear is meshed on the second gear, a second bevel gear is connected to the first gear, and the first bevel gear is meshed on the second bevel gear. However, the technical solution can only measure and detect the bottom of the glass bottle, and cannot measure the thickness of other areas of the glass bottle.

[0006] At present, vernier calipers are often used to detect the thickness of bottle tube parts. This detection method is not only inefficient, but also very time-consuming. In addition, the detection accuracy of manual detection is low. In addition, during the detection, due to the rounded appearance of bottle tube parts, it is difficult to fix them and they are prone to detachment. Summary of the invention

[0007] The purpose of the present invention is to solve the technical problems of low measurement efficiency, time waste and low detection accuracy when detecting the thickness of existing bottle tube parts. The present invention provides a three-dimensional detection device for bottle tube parts, which can accurately detect bottle tube parts, has high detection efficiency, and can realize three-dimensional detection of bottle tube parts.

[0008] In order to solve the above technical problems, the embodiment of the present invention discloses a three-dimensional detection device for bottle tubes, comprising:

[0009] A workbench, on which a fixing assembly is arranged, and the fixing assembly can drive the bottle tube to move to the center of the fixing assembly and fix the bottle tube;

[0010] A fixing rod, fixedly installed on a workbench in a vertical direction;

[0011] A first detection assembly, the first detection assembly includes a first detection probe and a first transmission mechanism, the first detection probe is arranged above the center of the fixed assembly, and the first transmission mechanism can drive the first detection probe to move in a vertical direction;

[0012] A clamping assembly is slidably mounted on the fixing rod, and the clamping assembly includes a clamping claw, and the clamping claw is used to clamp the bottle tube;

[0013] A second detection component is arranged on the workbench, and the second detection component includes a second detection probe and a second transmission mechanism, and the second transmission mechanism can drive the second detection probe to reciprocate in a horizontal direction toward the center of the fixed component;

[0014] The third detection component is arranged on the workbench. The third detection component includes a third detection probe and a third transmission mechanism. The third transmission mechanism can drive the third detection probe to move in a vertical direction.

[0015] By adopting the above technical solution, accurate detection of bottle tube components can be achieved with high detection efficiency, and three-dimensional detection of bottle tube components can be achieved.

[0016] According to another specific embodiment of the present invention, the embodiment of the present invention discloses that the clamping assembly further includes:

[0017] A sliding part, which is provided with a through hole, and the sliding part is sleeved on the fixing rod through the through hole;

[0018] A first driving mechanism is disposed on the sliding portion, the clamping jaw is mounted on the first driving mechanism, and is controlled by the first driving mechanism to open and close and rotate around its axis;

[0019] The power mechanism is electrically connected to the first driving mechanism and is used to provide power to the first driving mechanism.

[0020] According to another specific embodiment of the present invention, the embodiment of the present invention discloses that the fixing assembly includes:

[0021] The chuck is in the shape of a disc and is placed on a workbench. Four slide grooves are provided along the center of the chuck, and the angle between two adjacent slide grooves is 90°.

[0022] Four claws are slidably installed in four slide grooves respectively;

[0023] The second driving mechanism is arranged in the workbench, and includes a driving motor, a bevel gear and a wire coil. The bevel gear is meshed and connected with the wire coil. There are four bevel gears and four wire coils respectively. The four wire coils are respectively connected to the bottoms of four claws. When the bevel gear rotates, the bevel gear can drive the wire coil to rotate, and the wire coil can drive the claw to move along the slide groove. The driving motor is respectively connected to the four bevel gears for controlling the synchronous rotation of the four bevel gears.

[0024] According to another specific embodiment of the present invention, the embodiment of the present invention discloses a display instrument, which is signal-connected to the first detection component, the second detection component and the third detection component respectively, receives detection data from the first detection component, the second detection component and the third detection component, and the display instrument can convert the detection data into detection results based on a conversion formula.

[0025] According to another specific embodiment of the present invention, the embodiment of the present invention discloses that the first detection probe includes:

[0026] The measuring part includes a sensitive element and an elastic element. The sensitive element is arranged at the end of the elastic element. The elastic element can be elastically deformed when it contacts the bottle tube. The resistance value of the sensitive element can change when the elastic element is deformed.

[0027] The measuring circuit is electrically connected to the sensitive element and is used to convert the resistance change of the sensitive element into an electrical signal and send the electrical signal to the display instrument.

[0028] According to another specific embodiment of the present invention, the embodiment of the present invention discloses that the second detection probe includes:

[0029] A plurality of second probes are arranged at equal intervals in the vertical direction, and ends of the second probes are flush;

[0030] The second probe is mounted on the fixing part, and the fixing part is connected to the second transmission mechanism.

[0031] According to another specific embodiment of the present invention, the embodiment of the present invention discloses that the third detection probe includes:

[0032] The probe housing is conical, and the end of the probe housing is hemispherical;

[0033] A piezoelectric crystal is disposed in the probe housing and at an end of the probe housing;

[0034] A buffer member is arranged between the piezoelectric crystal and the probe housing;

[0035] Among them, the piezoelectric crystal is connected with the display instrument signal.

[0036] According to another specific embodiment of the present invention, the embodiment of the present invention discloses that it also includes a printer, which is arranged in the workbench, and the printer is connected to the display instrument signal for printing the detection results.

[0037] According to another specific embodiment of the present invention, the embodiment of the present invention discloses a conversion formula:

[0038]

[0039] Among them, △R is the resistance change, R is the initial resistance, π is the piezoresistance coefficient, σ is the stress, d is the thickness of the bottle and tube fitting, k is the stress concentration coefficient of the bottle and tube fitting, f is the elastic modulus function of the bottle and tube fitting, and P is the external force.

[0040] The beneficial effects of the present application are as follows: by providing a three-dimensional detection device for bottle tube parts, accurate detection of bottle tube components can be achieved with high detection efficiency, and three-dimensional detection of bottle tube components can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram showing the structure of a three-dimensional detection device for a bottle tube according to an embodiment of the present invention Figure 1 ;

[0042] Figure 2 A schematic diagram showing the structure of a three-dimensional detection device for a bottle tube according to an embodiment of the present invention Figure 2 ;

[0043] Figure 3 A schematic structural diagram of a fixing assembly according to an embodiment of the present invention is shown.

[0044] Among them, 1. workbench; 2. fixing component; 21. chuck; 22. claw; 23. slide; 3. fixing rod; 4. clamping component; 5. first detection component; 51. first transmission mechanism; 52. first detection probe; 6. second detection component; 61. second transmission mechanism; 62. second detection probe; 7. third detection component; 71. third transmission mechanism; 72. third detection probe; 8. display; 9. printer; 10. PET preform; 11. guide rail. DETAILED DESCRIPTION

[0045] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0046] In the description of this embodiment, it should be noted that the terms "upper", "lower", "inner", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0047] The terms “first”, “second”, etc. are only used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0048] In the description of this embodiment, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this embodiment can be understood according to specific circumstances.

[0049] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0050] Reference Figure 1 and Figure 2 The present application provides a three-dimensional detection device for bottle tubes, comprising a workbench 1, on which a fixing assembly 2 is arranged, the fixing assembly 2 can drive the bottle tube to move to the center of the fixing assembly 2 and fix the bottle tube; a fixing rod 3, along the vertical direction ( Figure 1The first detection component 5 includes a first detection probe 52 and a first transmission mechanism 51. The first detection probe 52 is arranged above the center of the fixed component 2. The first transmission mechanism 51 can drive the first detection probe 52 to move in the vertical direction; the clamping component 4 is slidably mounted on the fixed rod 3. The clamping component 4 includes a clamping claw, which is used to clamp the bottle tube; the second detection component 6 is arranged on the workbench 1. The second detection component 6 includes a second detection probe 62 and a second transmission mechanism 61. The second transmission mechanism 61 can drive the second detection probe 62 to move in the horizontal direction ( Figure 1 The third detection component 7 is arranged on the workbench 1, and the third detection component 7 includes a third detection probe 72 and a third transmission mechanism 71. The third transmission mechanism 71 can drive the third detection probe 72 to move in the vertical direction.

[0051] In this embodiment, a device capable of performing three-dimensional detection on bottle tube components is provided, which can detect the wall thickness, bottom thickness, circularity and verticality of bottle tube components. The first transmission mechanism 51 can drive the first detection probe 52 to move in the vertical direction to obtain data on the bottom of the bottle tube component; the second transmission mechanism 61 can drive the second detection probe 62 to move in the horizontal direction ( Figure 1 The third transmission mechanism 71 can drive the third detection probe 72 to move along the vertical direction to obtain the wall thickness data of the bottle tube.

[0052] For the convenience of description, the present application takes a PET preform 10 as an example for illustration.

[0053] The first detection component 5 is used to detect the bottom thickness of the PET preform 10. The PET preform 10 is placed on the fixing component 2 in the vertical direction. The fixing component 2 can fix the PET preform 10 and drive the PET preform 10 to move closer to the center of the fixing component 2 to achieve automatic centering. The first detection probe 52 is arranged above the center of the fixing component 2, and is driven by the first transmission mechanism 51 to move toward the bottom of the PET preform 10 in the vertical direction until it abuts against the bottom of the PET preform 10. According to the data when the first detection probe 52 abuts against the bottom of the PET preform 10, the bottom thickness data of the PET preform 10 is obtained.

[0054] The second detection component 6 is used to detect the verticality of the PET preform 10. The PET preform 10 is fixed on the fixing component 2. The second transmission mechanism 61 can also drive the second detection probe 62 to move horizontally toward the PET preform 10 located at the center of the fixing component 2 to obtain the bottle body data of the PET preform 10 and perform verticality detection on the PET preform 10.

[0055] The third detection component 7 is used to detect the circumference and thickness of the PET preform 10. The third detection component 7 is provided with a workbench 1. The workbench 1 is provided with a guide rail 11 arranged in a horizontal direction. The third transmission mechanism 71 can move along the guide rail 11. The clamping component 4 clamps and fixes the PET preform 10. The clamping claw can clamp the PET preform 10 and drive the PET preform 10 to rotate around its axis. According to the detection needs, when the bottle body thickness of the PET preform 10 is detected, the third transmission mechanism 71 is moved to the PET preform 10 to be detected. The third transmission mechanism 71 drives the third detection probe 72 to move toward the PET preform 10 in the vertical direction to detect the thickness of the PET preform 10;

[0056] When performing circumference detection, the third transmission mechanism 71 drives the third detection probe 72 to move toward the PET preform 10 in the vertical direction until it abuts against the PET preform 10, and then the clamp drives the PET preform 10 to rotate to obtain the circumference data of the bottle body of the PET preform 10.

[0057] In this application, the first detection probe 52 uses a high-precision resistive displacement sensor with a range of 0-50mm and a measurement accuracy of ±0.03mm. The first transmission mechanism 51 is composed of a lead screw nut pair driven by a DC motor and a high-precision linear optical axis guide rail. The lead screw pitch is 0.8mm, and the DC motor speed can be accurately adjusted between 0-1500rpm, which can accurately control the vertical movement position of the first detection probe 52. The linear optical axis guide slider is connected to the bracket for installing the probe to ensure the linearity of the probe movement. When the first detection probe 52 contacts the bottom of the PET preform 10, the bottom thickness data of the PET preform 10 is obtained based on the resistance change and the calibration data conversion.

[0058] The second detection probe 62 adopts a mechanical contact probe. The end of the second detection probe 62 is a spherical sapphire contact with a diameter of 3-5mm. The use of sapphire contacts can effectively reduce the impact of wear on measurement accuracy by utilizing the high hardness and good wear resistance of sapphire. The contact of the second detection probe 62 is connected to a high-precision strain gauge force sensor with a measurement range of 0-10N and an accuracy of up to ±0.05N. When the contact of the second detection probe 62 contacts the PET preform 10 and rotates with the PET preform 10, it can accurately sense the change in contact force, thereby obtaining the flatness information of the surface of the PET preform 10, providing a data basis for verticality detection.

[0059] The second transmission mechanism 61 is composed of a ball screw pair driven by an AC servo motor and a linear guide rail to form a horizontal transmission part. The ball screw pitch is 1mm, and the control accuracy of the servo motor is 0.01mm. It can accurately control the second detection probe 62 to approach the PET preform 10 in the horizontal direction. The vertical transmission part is a synchronous belt drive and a guide column guide structure driven by a stepper motor. The synchronous belt transmission ratio is 2:1, the step angle of the stepper motor is 1.8°, the guide column diameter is 16mm, and the straightness error is controlled within ±0.02mm. The position adjustment of the second detection probe 62 in the vertical direction can be stably achieved. When the verticality of the PET preform 10 is detected, the second detection probe 62 is first moved to one side of the PET preform 10 through horizontal transmission, and then the height of the second detection probe 62 is adjusted to the middle position of the bottle body through vertical transmission. Then, the PET preform 10 rotates one circle with the fixing component 2. When the second detection probe 62 contacts the bottle body, the force sensor and the displacement sensor work together to collect data at each point of the bottle body, and the verticality deviation is obtained through data processing.

[0060] The third detection probe 72 adopts a resistive thickness detector with a resolution of 0.0005mm, which can accurately measure the thickness and circumference of the PET preform 10. When the bottle body thickness is detected, the clamping component 4 fixes the PET preform 10 and rotates it around the axis. The third transmission mechanism 71 moves the third detection probe 72 to the top of the position to be detected, and then drives the lead screw through the motor to make the third detection probe 72 vertically descend to contact the PET preform 10, and the bottle body thickness is calculated based on the resistance change. When the circumference is detected, the third detection probe 72 is also first moved to the side of the bottle and descended to contact the bottle body. The clamp drives the PET preform 10 to rotate, and the resistive thickness detector collects data in real time and analyzes the circumference data.

[0061] By adopting the above technical solution, accurate detection of bottle tube components can be achieved with high detection efficiency, and three-dimensional detection of bottle tube components can be achieved.

[0062] In an optional embodiment, the clamping assembly 4 further includes:

[0063] A sliding part, which has a through hole, and the sliding part is sleeved on the fixing rod 3 through the through hole;

[0064] A first driving mechanism is disposed on the sliding portion, the clamping jaw is mounted on the first driving mechanism, and is controlled by the first driving mechanism to open and close and rotate around its axis;

[0065] The power mechanism is electrically connected to the first driving mechanism and is used to provide power to the first driving mechanism.

[0066] In this embodiment, the clamp is made of stainless steel, which has good corrosion resistance and mechanical strength. The clamping surface of the clamp is designed to be an arc that matches the shape of the PET preform 10. The radius of the arc is determined according to the outer diameter of the common PET preform 10, and the error is controlled within ±1mm to ensure that the PET preform 10 can be stably clamped. A layer of soft silicone pad is also pasted on the clamping surface. The thickness of the silicone pad is 3-5mm and the Shore hardness is 30-40. It can effectively buffer the clamping force and prevent the PET preform 10 from breaking due to excessive force, and can further increase the friction force to prevent the PET preform 10 from slipping during the clamping process. The opening and closing angle range of the clamp is 0-120°. The first driving mechanism can accurately control any opening and closing angle of the clamp within this range to meet the clamping requirements of PET preforms 10 of different sizes.

[0067] The through hole of the sliding part is processed by high-precision boring technology, and the inner diameter tolerance of the through hole is ±0.05mm. A clearance fit is adopted between the sliding part and the fixed rod 3 to ensure that the sliding part can slide smoothly on the fixed rod 3 with minimal shaking. The sliding part is made of aluminum alloy, which has the characteristics of light weight and high strength, and is easy to move and position quickly in the equipment.

[0068] The first drive mechanism is a combination of a stepper motor and a planetary reducer. The step angle of the stepper motor is 1.8°, and the output torque is amplified by the planetary reducer. The reduction ratio of the planetary reducer is 50:1, so that the first drive mechanism can output a larger torque to control the opening and closing and rotation of the clamp. The output shaft of the motor is connected to a ball screw through a coupling. The pitch of the ball screw is 2mm. When the motor rotates, the ball screw can convert the rotational motion into linear motion, thereby driving the clamp to open and close. A rotating shaft is installed on the nut seat of the ball screw, and the clamp is fixed on the rotating shaft. A worm gear mechanism is installed on the rotating shaft to realize the rotation of the clamp around its axis. The transmission ratio of the worm gear is 30:1, which can accurately control the rotation angle of the clamp, and the rotation angle accuracy can reach ±0.5°.

[0069] The power mechanism is powered by a DC power supply with an output voltage of 24V and a current of 5A, which can stably provide power for the first drive mechanism. A power management module is provided inside the power mechanism, which can monitor and adjust the output voltage and current in real time. When the voltage fluctuation exceeds ±5% or the current is overloaded, the output parameters are automatically adjusted to ensure the normal operation of the first drive mechanism. The power mechanism and the first drive mechanism are connected by a shielded cable. The length of the cable is determined according to the equipment layout, generally 1-3 meters, which can effectively reduce the impact of electromagnetic interference on signal transmission.

[0070] Continue to refer to Figure 3 In an optional embodiment, the fixing component 2 includes:

[0071] The chuck 21 is in the shape of a disk and is disposed on the workbench 1. Four slide grooves 23 are provided extending outward from the center of the chuck 21, and the angle between two adjacent slide grooves 23 is 90°.

[0072] Four claws 22 are slidably mounted in four slide slots 23 respectively;

[0073] The second driving mechanism is arranged in the workbench 1, and includes a driving motor, a bevel gear and a wire coil. The bevel gear is meshed with the wire coil. There are four bevel gears and four wire coils respectively. The four wire coils are respectively connected to the bottoms of four claws 22. When the bevel gear rotates, the bevel gear can drive the wire coil to rotate, and the wire coil can drive the claw 22 to move along the slide groove 23. The driving motor is respectively connected to the four bevel gears for controlling the synchronous rotation of the four bevel gears.

[0074] In this embodiment, the chuck 21 is made of high-strength alloy steel and has good wear resistance and deformation resistance. Its disc-shaped design ensures stable support for the workpiece in all directions. A central positioning hole is provided at the center of the chuck 21, and the accuracy of the positioning hole can reach ±0.05mm, which is used to accurately match the positioning axis of the workbench 1 during installation to ensure the accuracy of the installation position of the chuck 21. The four slide grooves 23 are all processed by precision milling technology. The width tolerance of the slide groove 23 is controlled within ±0.1mm, and the depth tolerance is controlled within ±0.15mm, so as to ensure that the claw 22 can slide smoothly in the slide groove 23 with a small gap to reduce shaking.

[0075] A rubber pad is provided on the top of each clamping claw 22. The Shore hardness of the rubber pad is 60-70 and the surface has an anti-skid texture. The design of this rubber pad can not only effectively protect the surface of the clamped workpiece and prevent it from being scratched, but also increase the friction between the clamping claw 22 and the workpiece, thereby improving the stability of the clamping. The bottom of the clamping claw 22 and the connection part of the wire coil adopt a special connection structure, which is connected to the wire coil through a connecting sleeve with a keyway. The keyway cooperates with the key on the wire coil to ensure that the clamping claw 22 can accurately move along the slide groove 23 under the drive of the wire coil without relative rotation. The side of the clamping claw 22 is provided with a scale mark with a scale accuracy of 0.1mm, which is convenient for the operator to intuitively read the opening or closing size of the clamping claw 22 when adjusting the position of the clamping claw 22.

[0076] The drive motor adopts a high-precision servo motor with an output torque range of 5-10N・m and a speed that can be precisely adjusted between 0-1000rpm. The output shaft of the motor is connected to a main drive shaft through a coupling. Four bevel teeth are installed on the main drive shaft, and each bevel tooth engages with the corresponding coil. When the drive motor receives a control signal and starts to rotate, the main drive shaft drives the four bevel teeth to rotate synchronously. The modulus of the bevel teeth and the coil are both 2, and the pressure angle is 20°. This parameter design can ensure high efficiency and stability in the power transmission process. The pitch of the coil is 5mm. Driven by the bevel teeth, the claw 22 moves 5mm along the slide 23 for every rotation of the coil, so that the four claws 22 can approach or withdraw from the center at the same time, realizing the automatic centering function.

[0077] In an optional embodiment, the first detection probe 52 includes:

[0078] The measuring part includes a sensitive element and an elastic element. The sensitive element is arranged at the end of the elastic element. The elastic element can be elastically deformed when it contacts the bottle tube. The resistance value of the sensitive element can change when the elastic element is deformed.

[0079] The measuring circuit is electrically connected to the sensitive element and is used to convert the resistance change of the sensitive element into an electrical signal and send the electrical signal to the display instrument 8.

[0080] In this implementation, the sensitive element uses a high-precision metal foil strain gauge with a resistance value of 120Ω±0.5Ω and a strain sensitivity coefficient between 2.0-2.2. The strain gauge is made using a special photolithography process, with a grid wire width of 0.03-0.05mm and a length of 3-5mm, which can accurately sense tiny strain changes. When the elastic element is deformed, the resistance change rate of the strain gauge is proportional to the strain, and its linearity error is controlled within ±0.1%, which can effectively improve the accuracy of the measurement.

[0081] The elastic element is made of high-quality spring steel. After quenching and tempering, the hardness reaches HRC40-45, and it has good elasticity and fatigue resistance. The elastic element is designed as a cylindrical cantilever beam structure with a diameter of 6-8mm and a length of 20-30mm. A circular groove is set at the free end of the cantilever beam, and the strain gauge is pasted at the bottom of the groove. When the elastic element collides with the bottom of the pet bottle embryo 10, the cantilever beam bends and deforms, and the strain gauge generates strain, thereby causing the resistance value to change. The elastic modulus of the elastic element is 200-220GPa. Within the measurement range, its deformation and force show a good linear relationship, and the maximum deformation does not exceed 0.5mm, which can ensure stable performance during multiple measurements.

[0082] The measurement circuit uses a Wheatstone bridge circuit, and the sensitive element (strain gauge) is connected to one arm of the bridge. The other three arms of the bridge use precision resistors with a resistance accuracy of ±0.02%. A stable DC voltage source with a voltage value of 5V±0.05V is connected to the input of the bridge. When the resistance value of the strain gauge changes, the bridge loses balance and outputs a weak voltage signal. The measurement circuit also includes a high-precision operational amplifier with an amplification factor of 100-200 times, which is used to amplify the weak voltage signal output by the bridge. The operational amplifier uses a low-noise, low-offset voltage chip with an offset voltage of no more than 1mV and a noise voltage density of less than 10nV / Hz, which can effectively improve the quality of the signal.

[0083] The amplified electrical signal is filtered through a low-pass filter with a cutoff frequency of 100Hz, which can effectively filter out high-frequency noise interference. The filtered signal is then transmitted to an A / D converter, which uses a 12-16-bit high-precision chip with a sampling frequency of 1kHz-2kHz to convert the analog electrical signal into a digital signal. The digital signal is transmitted to the display 8 through the data bus. The display 8 uses a liquid crystal display screen, which can intuitively display the measurement data of the bottom thickness of the pet preform 10, with a display accuracy of 0.01mm. At the same time, the measurement circuit also has a data storage function, which can store the latest 100 measurement data for subsequent query and analysis.

[0084] In an optional embodiment, the second detection probe 62 includes:

[0085] A plurality of second probes are arranged at equal intervals in the vertical direction, and ends of the second probes are flush;

[0086] The fixing part, on which the second probe is mounted, is connected to the second transmission mechanism 61 .

[0087] In this embodiment, each second probe is made of hard alloy material, which has high hardness and wear resistance, ensuring that it is not easy to wear and deform during frequent contact with the PET preform 10, thereby ensuring the stability of measurement accuracy. The end of the probe is designed to be a hemispherical shape with a radius of 2-3mm, which can effectively reduce stress concentration when in contact with the bottle body and avoid scratching the surface of the PET preform 10. The length of the probe is 10-15mm and the diameter is 4-6mm. This size design can not only meet the effective detection of different positions of the bottle body, but also ensure the compactness of the structure.

[0088] The number of second probes arranged at equal intervals in the vertical direction is 5-8, which is determined according to the common height range and detection accuracy requirements of the PET preform 10. The spacing between adjacent second probes is 20-30mm, which can obtain the contour data of the PET preform 10 in the vertical direction more comprehensively, so as to analyze its verticality more accurately. For example, for a PET preform 10 with a height of 100-200mm, 7 probes with a spacing of about 25mm can better cover the detection range, and the difference in the detection data of adjacent probes can intuitively reflect the bending or tilt of the bottle body.

[0089] The fixing part is made of aluminum alloy and is installed with the second probe through interference fit through precision-machined mounting holes. The interference is controlled at 0.02-0.05mm to ensure the firmness of the probe installation and prevent it from loosening. The fixing part is rectangular in shape as a whole. Its size is optimized according to the number and layout of probes. The length is 80-120mm, the width is 30-50mm, and the thickness is 15-25mm. It has sufficient rigidity to carry the probe and keep its relative position stable.

[0090] The fixing part is connected to the second transmission mechanism 61 by bolts, the bolt specifications are M4-M6, and the pre-tightening torque is between 3-5N·m, ensuring reliable connection and easy disassembly and maintenance. A positioning pin is provided on the connection surface between the fixing part and the second transmission mechanism 61, and the diameter of the positioning pin is 3-5mm, which can accurately ensure the installation position accuracy of the fixing part on the transmission mechanism, and the positioning error is controlled within ±0.1mm, so that the probe always maintains an accurate posture and position relationship during the movement process.

[0091] In an optional embodiment, the third detection probe 72 includes: a probe shell, which is conical in shape, and the end of the probe shell is hemispherical in design; a piezoelectric crystal, which is arranged in the probe shell and at the end of the probe shell; a buffer, which is arranged between the piezoelectric crystal and the probe shell; wherein the piezoelectric crystal is connected to the display 8 signal.

[0092] In this embodiment, the probe housing is made of high-strength stainless steel, which has good corrosion resistance and mechanical strength and can adapt to various detection environments. The conical probe housing has a large end diameter of 10-15 mm, a small end diameter (i.e., the diameter of the hemispherical part of the end) of 3-5 mm, and a length of 15-20 mm. This size design is convenient for operation and positioning, and can ensure that the internal piezoelectric crystal has enough space for deformation sensing. At the same time, the hemispherical design of the end can effectively reduce wear and stress concentration when contacting the PET bottle embryo 10.

[0093] The probe housing surface is finely polished, and the surface roughness Ra does not exceed 0.8 μm, so as to reduce the friction with the surface of the PET preform 10 during the detection process, avoid scratches or other damage to the surface of the PET preform 10, and help improve the accuracy and stability of the detection.

[0094] The piezoelectric crystal is made of high-quality piezoelectric ceramic material, and its piezoelectric constant d33 is not less than 300pC / N. It has high sensitivity and can accurately convert mechanical pressure into electrical signals. When subjected to slight pressure changes, it can produce obvious charge changes, thereby accurately reflecting the thickness and circumference changes of the PET preform 10. The Curie temperature of the piezoelectric crystal is between 300-350°C, and it can maintain stable piezoelectric performance within the normal operating temperature range, and will not produce large measurement errors due to temperature changes.

[0095] The piezoelectric crystal is fixed in the probe housing with elastic glue, and the elastic modulus of the elastic glue is 1-2MPa, which can not only ensure the stable fixation of the piezoelectric crystal in the probe housing, but also buffer the external impact force to a certain extent and protect the piezoelectric crystal from damage. The central axis of the piezoelectric crystal coincides with the central axis of the probe housing, and the installation position deviation does not exceed ±0.05mm, ensuring uniform force during the detection process and improving measurement accuracy.

[0096] The buffer is made of silicone rubber, which has good elasticity and buffering performance. It is annular in shape, 2-3mm thick, and wrapped between the outer side of the piezoelectric crystal and the inner wall of the probe housing. The Shore hardness of silicone rubber is 30-40. It can produce moderate deformation when under pressure, effectively absorb and disperse the impact force from the outside, prevent the piezoelectric crystal from being damaged by the instantaneous excessive impact force, and also reduce the interference of mechanical vibration and other factors on the measurement results.

[0097] When the probe contacts the PET preform 10, the impact force first acts on the probe housing, and then is transmitted to the piezoelectric crystal after being buffered by the deformation of the buffer, so that the piezoelectric crystal is subjected to a relatively uniform and stable pressure, thereby generating an accurate electrical signal. The buffer can also compensate for the internal stress that may be generated due to the different thermal expansion coefficients of the probe housing and the piezoelectric crystal to a certain extent, further improving the working stability and service life of the piezoelectric crystal.

[0098] In the present application, the probe housing is the external protective structure of the detection probe. It is usually made of metal (such as stainless steel). The metal housing has better wear resistance and corrosion resistance and can adapt to relatively harsh detection environments. It is generally cylindrical or rectangular, and its end will be a point contact probe, which is a small hemispherical or conical shape, so that it can accurately contact the surface point of the object being measured. The sensitive element is the core part of the probe, which can sense the change of physical quantity related to the wall thickness. Piezoelectric crystal is a material that can convert mechanical energy into electrical energy. When the probe housing contacts the surface of the PET preform 10 and is subjected to pressure changes (due to different wall thicknesses), the lattice structure of the piezoelectric crystal is deformed, thereby generating a charge change. This charge change is proportional to the pressure, and the wall thickness information of the PET preform 10 can be indirectly obtained by measuring the charge change. The piezoelectric crystal is electrically connected to the display 8 through a signal transmission line, which is responsible for transmitting the electrical signal generated by the sensitive element to the display 8. It is usually composed of multiple copper wires and is wrapped with an insulating layer.

[0099] The buffer is located between the end of the probe housing and the piezoelectric crystal. Its main function is to buffer the impact force generated when the end of the probe housing contacts the PET preform 10, protecting the piezoelectric crystal from damage. At the same time, it can also improve the contact performance between the end of the probe housing and the PET preform 10 to ensure the accuracy of the measurement. The buffer is usually made of elastic materials such as rubber and silicone, and has good elasticity and flexibility. In an optional embodiment, it also includes a printer 9, which is arranged in the workbench 1. The printer 9 is connected to the display 8 for printing the test results.

[0100] In this embodiment, the printer 9 is mainly used to print out the display results of the display instrument 8. Considering the working environment and the printing quality requirements, according to the size of the workbench 1, the printer 9 is usually a thermal printer 9 or a micro-pin printer 9. According to the advantages of the thermal printer 9, such as fast printing speed, low noise and simple maintenance, the printing resolution is selected to be 203dpi-300dpi, so that it can meet the clear printing of the test results. For the test report that needs to be preserved for a long time, the micro-pin printer 9 is selected. The micro-pin printer 9 forms characters by hitting the paper with a ribbon and a needle, and the printed content has good durability. The printing speed of the micro-pin printer 9 is usually about 1-4 lines per second, and models with different printing speeds can be selected according to actual needs.

[0101] The printer 9 is placed inside the workbench 1. To ensure its stable operation, a relatively stable, dry and convenient location for operation and maintenance should be selected. Sufficient space should be reserved inside the workbench 1. Generally, the installation space of the printer 9 is required to be not less than 200mm×150mm×100mm in length, width and height.

[0102] The printer 9 is fixed on the metal bracket inside the workbench 1 by bolts. The bolt specifications are M4-M6, and the pre-tightening torque is between 3-5N·m to ensure that the printer 9 will not shift due to vibration during operation. At the same time, a shock-absorbing pad is installed at the bottom of the printer 9. The shock-absorbing pad is made of rubber material with a thickness of 3-5mm and a Shore hardness of 30-40, which can effectively reduce the vibration and noise generated by the printer 9 when it is working.

[0103] In an practicable embodiment, a display device 8 is further included, which is connected to the first detection component 5, the second detection component 6 and the third detection component 7 by signals, receives the detection data from the first detection component 5, the second detection component 6 and the third detection component 7, and can convert the detection data into the detection result based on the conversion formula. The display device 8 is used to convert the detection data into display data according to the detection data through the conversion formula. For example, the display device 8 obtains the bottom data of the PET preform 10 according to the first detection component 5, such as the distance value from each point on the bottom to the first detection probe 52. After receiving these distance data, the display device 8 first sorts and filters the data to remove abnormal values ​​(data points that may be significantly deviated from the normal range due to measurement errors or impurities on the bottom of the bottle). Then, according to the geometric characteristics of the circle, the least squares method is used to fit the circular contour equation of the bottom of the circular bottle. Based on this equation, key parameters such as the radius and center coordinates of the bottom of the PET preform 10 can be calculated.

[0104] In an optional embodiment, the conversion formula is:

[0105]

[0106] Among them, △R is the resistance change, R is the initial resistance, π is the piezoresistance coefficient, σ is the stress, d is the thickness of the bottle and tube fitting, k is the stress concentration coefficient of the bottle and tube fitting, f is the elastic modulus function of the bottle and tube fitting, and P is the external force.

[0107] In this embodiment, a high-precision resistance measuring instrument can be used to measure the resistance change ΔR and the initial resistance R. In practical applications, a four-wire resistance measurement method is selected, and its measurement accuracy can reach ±0.01%. By contacting the measuring probe with the bottle tube, the resistance value measured when no external force is applied is the initial resistance R. When an external force is applied to the bottle tube, the difference between the resistance value measured again and the initial resistance R is the resistance change ΔR.

[0108] The measuring instrument uses a high-precision Wheatstone bridge circuit inside, and the excitation voltage of the bridge is stable at 5V±0.05V, which can accurately measure small resistance changes. At the same time, in order to reduce the temperature influence during the measurement process, the measuring probe and connecting lines are made of materials with low temperature coefficients to ensure the accuracy of resistance measurement within the operating temperature range, which is usually -10°C-50°C.

[0109] The piezoresistance coefficient π and the stress concentration coefficient k are usually material characteristic parameters obtained through a large number of experimental tests on bottle and tube fittings. For bottle and tube fittings of different materials, a corresponding material database needs to be established. During the experiment, standard tensile or compression test equipment is used to apply a precisely controllable external force P to the bottle and tube fitting sample, and the resistance change and stress change of the sample during the force process are measured.

[0110] Through fitting and analysis of multiple experimental data, the piezoresistance coefficient π and stress concentration coefficient k of different material bottles and tubes under different stress states are obtained. For example, for common glass material bottles and tubes, the piezoresistance coefficient π is generally between 0.1-0.3, and the stress concentration coefficient k is between 1.2-1.5. These parameters can be adjusted according to the specific glass formula and production process.

[0111] The thickness d of the bottle and tube fittings can be measured by a high-precision laser rangefinder or ultrasonic rangefinder, with a measurement accuracy of ±0.05mm. During measurement, the rangefinder is aimed at a specific position of the bottle and tube fittings, and the thickness of the bottle and tube fittings is calculated by emitting and receiving laser or ultrasonic signals.

[0112] The measurement of stress σ can be achieved by sticking strain gauges on the surface of bottle pipes. The measurement accuracy of strain gauges can reach ±0.001με microstrain. By measuring the resistance change of strain gauges when the bottle pipes are stressed, combined with the strain-stress conversion formula of strain gauges, the stress σ value of the bottle pipes can be obtained.

[0113] The application of external force P can be controlled by a high-precision force sensor, and the measurement accuracy of the force sensor can reach ±0.01 N. When external force is applied to the bottle or tube, the force sensor monitors and feedbacks the applied external force in real time to ensure accurate control of the external force.

[0114] The relationship between stress σ and external force P is based on the basic principles of material mechanics. The stress concentration factor k is a factor that takes into account the local increase in stress caused by factors such as geometric shape and material unevenness when the bottle and pipe are subjected to force. In actual calculations, after the external force P is accurately measured by the force sensor, the stress σ value of the bottle and pipe can be directly calculated based on the predetermined stress concentration factor k.

[0115] For example, when a 10N external force P is applied to a bottle-tube fitting with a stress concentration factor k of 1.3, the stress on the bottle-tube fitting is .

[0116] Relationship between the thickness d of the bottle tube and the resistance change ΔR and the external force P

[0117] Functional relationship between the thickness d of the bottle tube and the resistance change ΔR and the external force P

[0118] It is based on the elastic modulus and piezoresistive effect of the material. In the actual calculation, the product of the piezoresistive coefficient π and the stress σ is first calculated based on the measured resistance change ΔR and the initial resistance R. Then, the thickness d of the bottle and tube is calculated through a complex mathematical model based on the relationship between the stress σ and the external force P and the elastic modulus of the bottle and tube.

[0119] This mathematical model is usually an empirical formula obtained by fitting and regression analysis of a large amount of experimental data. For example, for a bottle tube made of a certain glass material, the functional relationship between the thickness d of the bottle tube and the resistance change ΔR and the external force P may be: , where a, b, and c are coefficients determined experimentally.

[0120] In this application, the piezoresistive sensor is based on the piezoresistive effect, and its basic formula is , where △R is the resistance change, R is the initial resistance, π is the piezoresistance coefficient, and σ is the stress.

[0121] When the PET preform 10 is subjected to pressure, according to material mechanics, stress σ is related to pressure. The relationship can be expressed as , here are the coefficients related to the material and geometry of the pet preform 10.

[0122] Will Substituting into the piezoresistive effect formula, we can get .

[0123] Assuming that the thickness d of the PET preform 10 is related to the deformation △d of the PET preform 10 under pressure, according to Hooke's law, within the elastic range, ,Depend on and Available ,Right now .

[0124] Wherein, E is the elastic modulus of the PET preform 10 material, and k is the stress concentration factor.

[0125] When the piezoresistive sensor contacts the PET preform 10 and applies pressure, the deformation of the PET preform 10 causes the sensor resistance to change. In one embodiment, the proportionality coefficient m associated with the PET preform 10 and the sensor system makes the resistance change rate The relationship between the deformation △d of the PET preform 10 is as follows: .

[0126] Will Substitution Available , further deformation can be obtained .

[0127] make , where E, m, and k are constants related to materials and systems and need to be determined through experimental calibration.

[0128] Through the above derivation, we get the function relationship f. In actual measurement, as long as these constants are determined, we can get the The thickness d of the PET preform 10 is calculated based on the applied pressure P.

[0129] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above is a further detailed description of the present invention in conjunction with specific embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. Those skilled in the art may make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A three-dimensional detection device for bottle and tube fittings, characterized in that: include: A workbench (1) is provided with a fixing assembly (2) thereon, wherein the fixing assembly (2) is capable of driving the bottle tube member to move to the center of the fixing assembly (2) and fixing the bottle tube member; A fixing rod (3) fixedly mounted on the workbench (1) in a vertical direction; A first detection component (5), the first detection component (5) comprising a first detection probe (52) and a first transmission mechanism (51), the first detection probe (52) being arranged above the center of the fixed component (2), and the first transmission mechanism (51) being capable of driving the first detection probe (52) to move along the vertical direction; The first detection probe (52) comprises: The measuring part includes a sensitive element and an elastic element, wherein the sensitive element is arranged at the end of the elastic element, the elastic element can be elastically deformed when it contacts the bottle tube, and the resistance value of the sensitive element can change when the elastic element is deformed; A measuring circuit, electrically connected to the sensitive element, for converting a resistance change of the sensitive element into an electrical signal and sending it to a display instrument (8); A clamping assembly (4) is slidably mounted on the fixing rod (3), the clamping assembly (4) comprising a clamping claw, the clamping claw being used to clamp the bottle tube; a second detection component (6) disposed on the workbench (1), the second detection component (6) comprising a second detection probe (62) and a second transmission mechanism (61), the second transmission mechanism (61) being capable of driving the second detection probe (62) to reciprocate in a horizontal direction toward the center of the fixed component (2); A third detection component (7) is arranged on the workbench (1), the third detection component (7) comprising a third detection probe (72) and a third transmission mechanism (71), the third transmission mechanism (71) being capable of driving the third detection probe (72) to move along the vertical direction; A display device (8) is respectively connected to the first detection component (5), the second detection component (6) and the third detection component (7) by signals, receives detection data from the first detection component (5), the second detection component (6) and the third detection component (7), and the display device (8) is capable of converting the detection data into detection results based on a conversion formula; The conversion formula is: Among them, d is the thickness of the bottle tube, E is the elastic modulus, m is the proportionality coefficient, k is the stress concentration factor, P is the pressure, △R is the resistance change, and R is the initial resistance.

2. The three-dimensional detection device for bottle tubes according to claim 1, characterized in that: The clamping assembly (4) further comprises: A sliding portion, which is provided with a through hole, and the sliding portion is sleeved on the fixing rod (3) through the through hole; A first driving mechanism is provided on the sliding part, the clamping jaw is mounted on the first driving mechanism, and is controlled by the first driving mechanism to open and close and rotate around its axis; A power mechanism is electrically connected to the first driving mechanism and is used to provide power to the first driving mechanism.

3. The three-dimensional detection device for bottle tubes according to claim 1, characterized in that: The fixing component (2) comprises: The chuck (21) is in the shape of a circular disk. The chuck (21) is arranged on the workbench (1). Four slide grooves (23) are provided extending outward from the center of the chuck (21). The angle between two adjacent slide grooves (23) is 90°. Four claws (22) are slidably mounted in the four slide grooves (23) respectively; A second driving mechanism is arranged in the workbench (1), comprising a driving motor, a bevel gear and a wire coil, wherein the bevel gear is meshed with the wire coil, four bevel gears and four wire coils are respectively provided, and the four wire coils are respectively connected to the bottoms of four claws (22). When the bevel gear rotates, the bevel gear can drive the wire coil to rotate, and the wire coil can drive the claw (22) to move along the slide groove (23). The driving motor is respectively connected to the four bevel gears for controlling the synchronous rotation of the four bevel gears.

4. The three-dimensional detection device for bottle tubes according to claim 1, characterized in that: The second detection probe (62) comprises: A plurality of second probes are arranged at equal intervals in the vertical direction, and ends of the second probes are flush; A fixing part, on which the second probe is mounted, and the fixing part is connected to the second transmission mechanism (61).

5. The three-dimensional detection device for bottle tubes according to claim 1, characterized in that: The third detection probe (72) comprises: The probe housing is conical, and the end of the probe housing is hemispherical; A piezoelectric crystal is disposed in the probe housing and at an end of the probe housing; A buffer member, disposed between the piezoelectric crystal and the probe housing; Wherein, the piezoelectric crystal is connected to the display instrument (8) by signal.

6. The three-dimensional detection device for bottle tubes according to claim 1, characterized in that: It also includes a printer (9) which is arranged in the workbench (1); the printer (9) is connected to the display device (8) by signal and is used to print the test results.

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