阅读说明：本技术 一种通过测量角度反馈压力信号的压力传感表 (Pressure sensing meter for feeding back pressure signal by measuring angle ) 是由 宋涛 于 2021-08-19 设计创作，主要内容包括：本发明公开了一种通过测量角度反馈压力信号的压力传感表,包括：表盘、指针盘,中心轴,表盘安装在接头主体上端固定的机芯上,指针盘安装于中心轴上,指针盘上还有指针；接头主体底端开孔、内部中空且侧壁连接有弹簧管,弹簧管末端通过封口密封；封口顺序连接有固定连接臂、连杆、U形连接臂,U形连接臂上固定有齿轮传动臂,齿轮传动臂转动地安装在机芯中；中心轴上安装有齿轮,齿轮与齿轮传动臂上的齿形配合；中心轴上设置游丝；指针盘上安装有环形磁体,表盘背面正对于环形磁体的位置安装有角度感应器。根据本发明所提供的压力传感表,通过将角度传感器能将压力表机械检测到的角度信号转换成电信号,集成度高。(The invention discloses a pressure sensing meter for feeding back pressure signals by measuring angles, which comprises: the dial plate is arranged on a core fixed at the upper end of the joint main body, the pointer plate is arranged on the central shaft, and a pointer is arranged on the pointer plate; the bottom end of the joint main body is provided with a hole, the interior of the joint main body is hollow, the side wall of the joint main body is connected with a spring tube, and the tail end of the spring tube is sealed by a seal; the seal is sequentially connected with a fixed connecting arm, a connecting rod and a U-shaped connecting arm, a gear transmission arm is fixed on the U-shaped connecting arm, and the gear transmission arm is rotationally arranged in the machine core; a gear is arranged on the central shaft and is matched with the tooth form on the gear transmission arm; a hairspring is arranged on the central shaft; an annular magnet is arranged on the pointer disk, and an angle sensor is arranged at the position of the back of the dial plate opposite to the annular magnet. According to the pressure sensing meter provided by the invention, the angle sensor can convert the angle signal mechanically detected by the pressure meter into the electric signal, and the integration level is high.)

1. A pressure sensing gauge for feeding back a pressure signal by measuring an angle, comprising: the dial plate (1) is installed on a movement (102) fixed at the upper end of the joint main body (101), the pointer plate (2) is installed on the central shaft (3), and the pointer plate (2) is further connected with a pointer penetrating through the front face of the dial plate (1); the bottom end of the joint main body (101) is provided with an opening, the interior of the joint main body is hollow, the side wall of the joint main body is connected with a spring tube (103), and the tail end of the spring tube (103) is sealed by a seal (104); the seal (104) is sequentially connected with a fixed connecting arm (105), a connecting rod (106) and a U-shaped connecting arm (107), a gear transmission arm (108) is fixed on the U-shaped connecting arm (107), and the gear transmission arm (108) is rotatably arranged in the movement (102); the central shaft (3) is arranged in the movement (102), a gear (109) is coaxially arranged on the central shaft, and the gear (109) is matched with the tooth profile on the gear transmission arm (108); a balance spring (110) is arranged on the central shaft (3), the inner ring of the balance spring (110) is fixed on the central shaft (3), and the outer ring is fixed on the movement (102);

the dial is characterized in that the pointer disc (2) is provided with an annular magnet (4) coaxial with the central shaft (3), and the back of the dial (1) is provided with an angle sensor (5) at a position right opposite to the annular magnet (4).

2. The pressure sensing watch according to claim 1, characterized in that a PCB board for mounting the angle sensor (5) is attached to the back of the dial (1).

3. Pressure sensing watch according to claim 2, characterised in that the PCB board is mounted under the dial (1) and is forced on the contact body (101).

4. The pressure sensing gauge of claim 2, wherein the PCB board is provided with a signal processing circuit for converting a rotation angle signal of the ring magnet (4) sensed by the angle sensor (5) into an electric signal.

5. The pressure sensing meter of any one of claims 1 to 4, wherein the pointer plate (2) has a sunken platform for mounting the annular magnet (4) on the end surface close to the dial plate (1).

6. The pressure sensing gauge according to any one of claims 1 to 4, characterized in that the pointer plate (2) and the pointer are of injection molding structure and are integrally molded by a combined mold.

Technical Field

The invention relates to the technical field of pressure gauges, in particular to a pressure sensing gauge for feeding back pressure signals through measuring angles.

Background

Pressure gauges (pressure gauge) are instruments that measure and indicate pressures above ambient pressure, which are very common, using elastic elements as sensors, and are used in almost all fields of industrial processes and scientific research. The method is widely available in the fields of heating power pipe networks, oil and gas transmission, water and gas supply systems, vehicle maintenance plants and shops and the like. Especially in the industrial process control and technical measurement process, the mechanical pressure gauge is more and more widely applied due to the characteristics of high mechanical strength, convenient production and the like of the elastic sensitive element of the mechanical pressure gauge.

The pressure gauge is characterized in that the pressure gauge transmits pressure deformation to the pointer through elastic deformation of sensitive elements (a Bourdon tube, a diaphragm capsule, a corrugated tube and a spring tube) in the gauge and a conversion mechanism of a movement in the gauge, so that the pointer rotates to display pressure. The pressure gauge in the prior art has single function, can not directly feed back an electric signal, and has low integration level, so that improvement is needed.

Disclosure of Invention

In view of the above, an object of the present invention is to provide a pressure sensor meter for feeding back a pressure signal by measuring an angle, which can convert an angle signal detected by the pressure meter into an electrical signal by integrating an angle sensor at a central axis position of the pressure meter, and which has a high integration level.

To achieve the above object, the present invention provides a pressure sensing gauge feeding back a pressure signal by measuring an angle, comprising: the dial plate is arranged on a core fixed at the upper end of the joint main body, the pointer plate is arranged on the central shaft, and the pointer plate is also connected with a pointer penetrating to the front surface of the dial plate; the bottom end of the joint main body is provided with a hole, the interior of the joint main body is hollow, the side wall of the joint main body is connected with a spring tube, and the tail end of the spring tube is sealed by a seal; the seal is sequentially connected with a fixed connecting arm, a connecting rod and a U-shaped connecting arm, a gear transmission arm is fixed on the U-shaped connecting arm, and the gear transmission arm is rotatably arranged in the machine core; the central shaft is arranged in the machine core, a gear is coaxially arranged on the central shaft, and the gear is matched with the tooth form on the gear transmission arm; the balance spring is arranged on the central shaft, the inner ring of the balance spring is fixed on the central shaft, and the outer ring of the balance spring is fixed on the machine core;

the pointer disc is provided with an annular magnet coaxial with the central shaft, and the back of the dial plate is provided with an angle sensor at a position right opposite to the annular magnet.

In some embodiments, a PCB board for mounting the angle sensor is attached to the back surface of the dial plate.

In some embodiments, all electronic components of the pressure sensing meter are attached to the PCB by a chip-on-package process.

In some embodiments, the PCB board is mounted under the dial and is forced over the connector body.

In some embodiments, a signal processing circuit is disposed on the PCB to convert a rotation angle signal of the ring magnet, which is sensed by the angle sensor, into an electrical signal.

In some embodiments, the end face of the pointer disk close to the dial is provided with a sunken platform for mounting a ring-shaped magnet.

In some embodiments, the spring tube is a bent tube made of stainless steel, and the joint body and the seal are hollow structures made of copper.

In some embodiments, the pointer plate and the pointer are in an injection molding structure and are integrally molded through a combined mold.

In some embodiments, the spring tube and the fitting body, and the spring tube and the seal are seamlessly connected by silver brazing.

Compared with the prior art, the invention has the beneficial effects that: the pressure sensing meter feeds back pressure signals by measuring angles is provided, when pressure changes, a spring tube deforms and drives a central shaft to rotate through a fixed connecting arm, a connecting rod, a U-shaped connecting arm, a gear transmission arm and a gear, so that an annular magnet is driven to rotate, the angle sensor can generate corresponding electric signals after detecting the change of a magnetic field on the annular magnet, the change of the signals is consistent with the rotating angle of a pointer, a pointer of a pressure meter does not need to be observed on site, the accurate pressure value on the site can be known remotely, and the integration level is high.

1. The pressure sensor can remotely acquire the field pressure value, and simultaneously can omit a pressure sensor, reduce the use cost and reduce the installation space.

2. The spring tube adopts the stainless steel tube, has excellent vibration resistance and fatigue resistance, is more suitable for the end use environment, and reduces the defective rate by 80 percent in the use process.

3. The electronic device is packaged and surface-mounted by adopting a surface mounting process, so that deviation caused by manual plug-in is avoided, manual adjustment and correction are not needed, and the consistency and stability of the product are greatly improved.

4. The joint and the seal are made of copper and are connected with the spring tube through silver brazing, so that the defect that micro leakage is easy to generate during copper brazing is overcome, the quality is improved, and the feasibility of mass production is improved.

5. The pressure sensing meter is convenient for automatic production, improves the production efficiency and saves the production cost.

Drawings

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

FIG. 1 is a schematic front view of an embodiment of the present invention;

FIG. 2 is a schematic view of the cross-sectional structure A-A of FIG. 1 according to the present invention;

figure 3 is a schematic perspective view of the movement of figure 2 according to the present invention;

FIG. 4 is a schematic diagram of an internal circuit of the angle sensor of the present invention;

FIG. 5 is a diagram showing the relationship between the output voltage of the angle sensor and the magnetic field.

In the figure: 1. a dial plate; 2. a pointer dial; 3. a central shaft; 4. a ring magnet; 5. an angle sensor; 101. a connector body; 102. a movement; 103. a spring tube; 104. sealing; 105. a fixed connecting arm; 106. a connecting rod; 107. a U-shaped connecting arm; 108. a gear transmission arm; 109. a gear; 110. a balance spring.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-5, fig. 1 is a schematic front view of an embodiment of the present invention; FIG. 2 is a schematic view of the cross-sectional structure A-A of FIG. 1 according to the present invention; figure 3 is a schematic perspective view of the movement of figure 2 according to the present invention; FIG. 4 is a schematic diagram of an internal circuit of the angle sensor of the present invention; FIG. 5 is a diagram showing the relationship between the output voltage of the angle sensor and the magnetic field.

The embodiment of the invention provides a pressure sensing meter for feeding back pressure signals by measuring angles, which comprises: the dial plate 1 is arranged on a movement 102 fixed at the upper end of a joint main body 101, the pointer plate 2 is arranged on the central shaft 3, the pointer plate 2 is also connected with a pointer penetrating to the front surface of the dial plate 1, namely an arc-shaped groove through which the pointer can deflect is reserved on the dial plate 1; the bottom end of the joint main body 101 is provided with a hole, the interior of the joint main body is hollow, the side wall of the joint main body is connected with a spring tube 103, and the tail end of the spring tube 103 is sealed by a seal 104; the seal 104 is sequentially connected with a fixed connecting arm 105, a connecting rod 106 and a U-shaped connecting arm 107, a gear transmission arm 108 is fixed on the U-shaped connecting arm 107, and the gear transmission arm 108 is rotatably arranged in the movement 102; the central shaft 3 is arranged in the movement 102, a gear 109 is coaxially arranged on the central shaft, and the gear 109 is matched with the tooth form on the gear transmission arm 108; a balance spring 110 is arranged on the central shaft 3, the inner ring of the balance spring 110 is fixed on the central shaft 3, and the outer ring is fixed on the movement 102;

an annular magnet 4 coaxial with the central shaft 3 is arranged on the pointer disc 2, and an angle sensor 5 is arranged at the position of the back surface of the dial plate 1 opposite to the annular magnet 4. The ring magnet 4 was magnetized radially with a rubidium magnet N35H, an outer diameter of 7MM, an inner diameter of 2MM, and a thickness of 1 MM. The angle sensor 5 is a custom Anisotropic Magnetoresistive (AMR) sensor, SOP8 look-and-feel package. The magnet center is aligned with the chip center at a distance of 1.5-3MM during mounting. The (AMR) sensor internal circuit schematic is shown in fig. 4: the principle is that two pairs of AMR Wheatstone bridges integrated in a chip can output two paths of sine and cosine analog voltage signals along with the direction change of an external magnetic field, the signals are amplified and filtered by an analog front-end circuit and then sent to a digital-to-analog converter (ADC), the amplified and digitized sine and cosine signals finally enter a Digital Signal Processor (DSP) to be compensated according to parameters of an EEPROM, and the calculation of calibration and angle solving is carried out.

As shown in fig. 5, a curve of an angle relationship between an output voltage of an AMR sensor and a magnetic field, which is solidified in an EEPROM when the curve is shipped from a factory, has a linear section and a nonlinear section, and a proportional curve becomes extremely flat or steep in the nonlinear section, which may cause a large error in an angle outputted by an operation.

In the whole machine assembling process, the center position of the magnetic field of the magnet and the center of the AMR sensor generate slight deviation due to part structure and machining assembling errors, and the deviation can cause errors of a measured angle. In a theoretical state, if the center of the magnetic force line of the magnet is aligned with the center of the sensor, the phase angle of the voltage output by the two bridges is different by 90 degrees. In practical cases, if the centers of the two are not aligned, the phase angle of the output voltage is not 90 degrees. In order to compensate the error, a calibration process is carried out after the assembly is finished, a group of data is collected under a certain angle, an absolute angle theta 1 and a phase difference eta 1 of two bridges are obtained through curve calculation, the magnet rotates to another angle, a group of data is collected, the absolute angle theta 2 and the phase difference eta 2 of the two bridges are obtained through curve calculation, the circle center difference angle and the difference distance between the two bridges can be calculated according to the angle difference delta theta 1 and the phase difference delta eta 2 of the absolute angles theta 1 and theta 2 and the bridge absolute value output under the two angles, the parameter is stored in an EEPROM after being calibrated, the parameter is read after the chip is powered on to operate, and the absolute angle calculation process is corrected, and the compensation operation process is carried out.

During the assembling process of the meters, the magnets are randomly installed, namely the absolute angle of the magnetic force line of each meter magnet is random under the same pressure. After the instrument is assembled, the absolute angle and the relative relationship between the pressure and the output voltage need to be established. The setup procedure is as follows, assuming that at two points of calibration, the first point pressure is assumed to be 0, the second point pressure is assumed to be full stroke, the first pressure point output voltage is assumed to be 0.5V, and the full stroke voltage is assumed to be 4.5V. Firstly, acquiring under the pressure of 0 to obtain an absolute angle 1, then acquiring under the full range pressure to obtain an absolute angle 2, and then writing the absolute angle 1, the absolute angle 2, the zero voltage 0.5 and the full range voltage 4.5 into the EEPROM. Then, the chip acquires, solves, compensates and calculates a real-time absolute angle 0 in real time when running, and outputs Vout (0.5 + (absolute angle 0-absolute angle 1) × (4.5-0.5)/(absolute angle 2-absolute angle 1) in real time. Meanwhile, a low-voltage clamp value Vmin, a high-voltage clamp value Vmax and a level turning point DP are arranged in the chip, so that when the absolute angle 0 is smaller than the absolute angle 1 or larger than the absolute angle 2, the output voltage is clamped at a certain voltage, and the wrong output voltage is prevented from occurring. This is the calibration output process.

And finally outputting the calculated output data by a digital-to-analog converter (DAC). The EEPROM in the chip can be communicated through OWI or SPI bus, the proportional relation data of the output voltage and the rotation angle of the DAC, the upper and lower limits of the output voltage of the DAC, the magnetic field angle of the initial pressure zero position, the plurality of rotation angles, the calibration information of the corresponding output voltage and other internal parameters can be modified, and the EEPROM is tested and calibrated after the product is assembled. The output analog voltage can be output by a post-stage circuit according to the needs of products, or the data of the angle can be directly read by the MCU through OWI or SPI bus and converted into field digital logic link (485, HART) and the like for transmission.

During the specific use process of the pressure sensing meter: the connector main body 101 is connected with pressure, such as air pressure, when sensing pressure change, the spring tube generates deformation and drives the central shaft to rotate through the fixed connecting arm, the connecting rod, the U-shaped connecting arm, the gear transmission arm and the gear, so that the annular magnet is driven to rotate, the angle sensor can generate corresponding electric signals after detecting the change of the magnetic field on the annular magnet, the change of the signals is consistent with the rotating angle of the pointer, the pointer of the pressure gauge does not need to be observed on site, the accurate pressure value on the site can be known in a long distance, and the integration level is high.

In order to realize the installation and fixation of the angle sensor, in this embodiment, optionally, a PCB board for installing the angle sensor 5 is attached to the back surface of the dial plate 1.

Furthermore, all electronic components of the pressure sensing meter are attached to the PCB through a chip packaging process.

Still further, the PCB is arranged below the dial 1 and stressed on the joint main body 101, so that the stability of the PCB is enhanced.

Still further, a signal processing circuit is disposed on the PCB for converting the rotation angle signal of the ring magnet 4 sensed by the angle sensor 5 into an electrical signal.

For better installation of the annular magnet 4, in the embodiment, the pointer plate 2 has a sinking platform for installing the annular magnet 4 on the end surface close to the dial plate 1.

In order to avoid welding missing, in this embodiment, the spring tube 103 is formed by a bent tube made of stainless steel, and the joint main body 101 and the seal 104 are formed by a cavity made of copper.

In order to ensure the consistency of pointer production, in this embodiment, optionally, the pointer disk 2 and the pointer are in an injection molding structure and are integrally molded through a combined mold.

In order to avoid welding leakage, in the present embodiment, optionally, the spring tube 103 and the joint main body 101, and the spring tube 103 and the seal 104 are seamlessly connected by silver brazing.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.