Detection probe and fetal monitor

Abstract

The present invention provides a detection probe and fetal monitor. The detection probe includes a probe body and a mounting structure detachably mounted to the probe body. The mounting structure is provided with a heart rate sensor for heart rate detection, a socket for data transmission, and lead wires connecting the heart rate sensor and the socket. This design allows a single detection device to perform multiple functions, achieving a high degree of integration. Furthermore, if the heart rate sensor malfunctions or ages, the mounting structure allows it to be separated from the probe body, requiring only repair and replacement of the corresponding components. This facilitates maintenance and reduces costs. The mounting structure also provides a degree of protection for the probe body, enhancing the detection probe's drop resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of medical equipment, and in particular to a detection probe and a fetal monitor. Background Art

[0002] Fetal heart rate is acquired using the ultrasonic Doppler effect. Ultrasonic waves are transmitted when they encounter tissue with varying density. Reflected by moving objects, they cause frequency shifts. These frequency shifts can be demodulated to represent tissue motion. By calculating the frequency of these movements, the heart's associated motion frequency can be determined, and thus the heart rate. Current technology demodulates and calculates all echoes within the probe's illumination range, making it very likely that blood vessels in the mother's abdomen will be measured. This can easily misidentify the mother's heart rate as the fetal heart rate when the mother's heart rate is high, leading to misdiagnosis.

[0003] In order to reduce the risk of this problem, fetal monitors have always measured the mother's heart rate while measuring the fetal heart rate, and compared the fetal heart rate with the mother's heart rate to determine whether the source of the fetal heart rate is correct.

[0004] Common methods for measuring a mother's heart rate include blood oxygen sensors (O2) or electrocardiogram (ECG). Both require sensors. O2 sensors typically use clip-on, ear clip-on, or forehead patch methods, while ECG sensors typically use lead wires attached to electrodes. Both methods require cables, which are not particularly comfortable to use and can interfere with the mother's movements.

[0005] For this reason, some blood oxygen technology solutions integrate a blood oxygen sensor into a uterine contraction probe. When in use, the sensor is placed against the pregnant woman's skin and, using blood oxygen technology, measures the blood oxygen signal in the tiny blood vessels in her abdomen and calculates her heart rate. This approach solves the cable issues associated with traditional solutions. However, since the sensor is integrated into the probe, the LED used in the blood oxygen sensor is subject to light decay, has a short lifespan, and is easily damaged. Integrating the sensor inside the probe makes maintenance difficult, requiring the entire probe to be replaced, resulting in additional repair costs for the user. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to overcome the defects in the prior art that the heart rate sensor integrated in other probe bodies is easily damaged, not conducive to maintenance, and requires the entire probe to be replaced, which brings additional maintenance costs to the user, thereby providing a detection probe and a fetal monitor.

[0007] The present invention provides a detection probe, comprising a probe body and a mounting structure detachably mounted on the probe body, wherein the mounting structure is provided with a heart rate sensor for heart rate detection, a socket for data transmission, and a lead wire connecting the heart rate sensor and the socket.

[0008] Optionally, the mounting structure is a shell structure that fits with the outer shell of the probe body and is detachably fastened to the probe body.

[0009] Optionally, the shell structure includes an active surface that fits the probe body and a connecting portion connected to the active surface, the connecting portion is wrapped around the outer peripheral edge of the probe body, the active surface fits the user during detection, and the heart rate sensor is arranged on the active surface.

[0010] Optionally, the heart rate sensor is an electrocardiogram electrode arranged on the active surface.

[0011] Optionally, the ECG electrodes include a left arm main electrode and a right arm main electrode for acquiring ECG signals of the left arm and the right arm respectively.

[0012] Optionally, it also includes at least one left arm secondary electrode set at a set distance from the left arm main electrode for obtaining electrocardiogram signals in the left arm area, and at least one right arm secondary electrode set at a set distance from the right arm main electrode for obtaining electrocardiogram signals in the right arm area.

[0013] Optionally, two of the left arm sub-electrodes and two of the right arm sub-electrodes are provided, namely a first left arm sub-electrode and a second left arm sub-electrode, and a first right arm sub-electrode and a second right arm sub-electrode.

[0014] Optionally, a lead axis formed by the left arm main electrode and the second right arm auxiliary electrode is perpendicular to a lead axis formed by the right arm main electrode and the second left arm auxiliary electrode.

[0015] Optionally, a right leg drive electrode is included to improve the system's common-mode rejection capability.

[0016] Optionally, the lead wire is arranged between the active surface and the probe body, and the shell structure is provided with a through hole allowing the heart rate sensor to pass through.

[0017] Optionally, the lead wire is a flexible FPC wire, or a conductive structure printed on a side of the shell structure facing the probe body.

[0018] Optionally, the heart rate sensor is a blood oxygen photoplethysmography sensor.

[0019] Optionally, the probe body is an external uterine contraction pressure probe, a fetal heart rate probe or an internal monitoring probe.

[0020] The present invention also provides a fetal monitor, comprising any one of the above detection probes.

[0021] The technical solution of the present invention has the following advantages:

[0022] 1. The present invention provides a detection probe comprising a probe body and a mounting structure detachably mounted on the probe body. The mounting structure is provided with a heart rate sensor for heart rate detection, a socket for data transmission, and a lead wire connecting the heart rate sensor and the socket. This design allows a single detection probe to achieve multiple functions, resulting in a high degree of integration. Furthermore, if the heart rate sensor malfunctions or ages, it can be separated from the probe body via the mounting structure, requiring only repair and replacement of the corresponding parts, thus facilitating maintenance and saving costs. Furthermore, the mounting structure also provides a certain degree of protection for the probe body, enhancing the detection probe's ability to resist falling.

[0023] 2. The present invention provides a detection probe, wherein the mounting structure is a shell structure that fits with the outer shell of the probe body and can be detachably snapped onto the probe body. Such a design not only enables detachable installation with the probe body, but also protects the probe body and improves the probe body's ability to resist falling.

[0024] 3. The present invention provides a detection probe, whose ECG electrodes include 7 ECG electrodes arranged around the center on the active surface. By combining two of them, signals at different angles to the ECG axis can be obtained to cover the standard ECG axis range, thereby reducing user operation actions; the optimal signal channel can be automatically adjusted through software and algorithms, and the probe placement can be automatically adjusted to the optimal ECG conduction direction to ensure the maximum and optimal signal, ensure the stability and reliability of the entire monitoring process, and reduce the impact of human operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is a schematic structural diagram of a detection probe provided in a first embodiment of the present invention;

[0027] Figure 2 for Figure 1 The schematic diagram of the mounting structure and ECG electrodes shown;

[0028] Figure 3 for Figure 1 The schematic diagram of the mounting structure, lead wire and socket shown;

[0029] Figure 4 for Figure 2 Working circuit diagram of the central electrode;

[0030] Figure 5 This is a schematic diagram of common lead directions in the frontal and horizontal planes of the human body;

[0031] Figure 6 This is a schematic structural diagram of an installation structure and ECG electrodes in a detection probe provided in a second embodiment of the present invention;

[0032] Figure 7 This is a flow chart of an embodiment of a heart rate acquisition method provided by the present invention.

[0033] Description of reference numerals:

[0034] 1-Mounting structure, 2-Probe body, 3-Active surface, 4-Socket, 5-Lead wire.

[0035] 101 - first differential amplifier, 102 - second differential amplifier, 103 - third differential amplifier, 104 - fourth differential amplifier, 105 - fifth differential amplifier, 106 - sixth differential amplifier, 107 - processing unit.

[0036] LA: left arm main electrode, LA1: first left arm secondary electrode, LA2: second left arm secondary electrode;

[0037] RA: right arm main electrode, RA1: first right arm auxiliary electrode, RA2: second right arm auxiliary electrode;

[0038] RL: right leg drive electrode. DETAILED DESCRIPTION

[0039] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0040] Figures 1 to 4 An embodiment of a detection probe provided by the present invention is shown.

[0041] The detection probe includes a probe body 2, a mounting structure 1, and a heart rate sensor. In this embodiment, the probe body 2 is an external uterine contraction pressure probe for detecting uterine contraction pressure. However, the probe body 2 is not limited to an external uterine contraction pressure probe and can be a probe for measuring other parameters of adults or fetuses, such as a fetal heart rate probe or an internal monitoring probe, and is not limited to a wired or wireless probe.

[0042] The probe body 2 includes an inner side surface that faces the user, an outer side surface opposite the inner side surface, and an outer peripheral surface connecting the inner and outer sides. The inner side surface includes a detection area that fits against the user to enable the detection function of the probe body 2. The outer side surface is provided with a strap buckle for the user to strap the detection probe to the abdomen.

[0043] The mounting structure 1 is a shell structure that fits with the outer shell of the probe body 2. The shell structure can be directly put on the outside of the probe body 2 and combined with the probe body 2 into one body, and can be freely disassembled from the probe body 2 and separated from the probe body 2. Specifically, the shell structure includes an active surface 3 that fits with the inner side surface of the probe body 2 and a connecting portion connected to the edge of the active surface 3. The active surface 3 is hollowed out corresponding to the detection area of ​​the inner side surface so that the probe body 2 can realize the detection function. The connecting portion is wrapped around the outer peripheral surface of the probe body 2, and the end has a snap-fit ​​portion that extends a set distance toward the center position of the probe body 2. The snap-fit ​​portion is used for the snap-fit ​​connection between the shell structure and the probe body 2. When the shell structure is installed on the probe body 2, it naturally becomes a protective shell of the probe body 2, further protecting the probe body 2 and improving the anti-drop ability of the detection probe.

[0044] To facilitate assembly and disassembly of the housing structure and the probe body 2, the housing structure is made of a deformable elastic material, such as plastic or silicone, though the housing material is not limited to these two materials. The thickness of the housing structure should be appropriate so as not to excessively increase the overall size of the detection probe and affect the user experience. This thickness can be determined based on the size of the probe body 2 and the design dimensions of the detection probe. In this embodiment, the thickness is 1 mm.

[0045] The active surface 3 is in contact with the user during testing, and the heart rate sensor is located on the active surface 3. The active surface 3 is provided with a through-hole for the heart rate sensor to pass through, and a hollow area corresponding to the detection area of ​​the probe body 2. In this embodiment, the hollow area is a circular structure, and the through-hole is provided on the outer periphery of the hollow area.

[0046] The heart rate sensor is an ECG electrode disposed on the active surface 3. The ECG electrode is made of a conductive material, including but not limited to copper, gold, stainless steel, and carbon. The shape can be square, flat, or circular, and the shape of the through hole corresponds to the shape of the ECG electrode.

[0047] like Figure 2As shown, in this embodiment, the ECG electrodes include seven electrodes arranged around the center of the active surface 3, forming an angle relative to the adult heart. These seven electrodes are the left arm main electrode LA, the first left arm secondary electrode LA1, the second left arm secondary electrode LA2, the right leg drive electrode RL, the second right arm secondary electrode RA2, the first right arm secondary electrode RA1, and the right arm main electrode RA. Due to differences between human bodies, the spacing and angles between the ECG electrodes can be freely set without specific restrictions.

[0048] The left arm main electrode LA and the right arm main electrode RA are fixed electrodes, which are used to obtain the ECG signals of the left arm and right arm of an adult, respectively.

[0049] The first and second left-arm secondary electrodes LA1 and LA2 are spaced a certain distance from the left-arm main electrode LA and serve as regional electrodes for acquiring ECG signals from the left arm of adults. The differential between the first left-arm secondary electrode LA1 and the right-arm main electrode RA, and the differential between the second left-arm secondary electrode LA2 and the right-arm main electrode RA, can acquire signals that differ from the differential between the left-arm main electrode LA and the right-arm main electrode RA, allowing for signals at different angles relative to the cardiac axis.

[0050] The first and second right-arm secondary electrodes RA1, RA2, are spaced a certain distance from the right-arm main electrode RA and serve as regional electrodes for acquiring ECG signals from the right arm of adults. The differential signals between the left-arm main electrode LA and the first right-arm secondary electrode RA1, as well as the differential signals between the left-arm main electrode LA and the second right-arm secondary electrode RA2, can acquire signals that differ from the differential signals between the left-arm main electrode LA and the right-arm main electrode RA, and can also acquire signals at different angles relative to the ECG axis.

[0051] Each cardiac cycle of the human heart is accompanied by the depolarization and repolarization process of myocardial cells. This bioelectric change is reflected to the body surface through the conductive tissues and body fluids around the heart, causing regular electrical changes in various parts of the body in each cardiac cycle. Electrodes are placed at appropriate positions on the limbs or torso to detect the electrical signals of different parts of the body, amplify and record the electrical activity of the heart, and obtain an electrocardiogram (ECG).

[0052] The size of the ECG waveform picked up by the ECG electrodes depends on the length of the projection of the ECG axis (average QRS vector) on the lead axis. Figure 5 In adults, a normal cardiac axis in three dimensions is oriented leftward and downward in the frontal plane, between leads I and aVF. In the horizontal plane, it is oriented posteriorly, between V6 and negative V2. The normal range of the frontal axis distribution in China is 0°-90°.

[0053] Please refer to Figure 2The lead axis formed by the left arm main electrode LA and the second right arm auxiliary electrode RA2 is perpendicular to the lead axis formed by the right arm main electrode RA and the second left arm auxiliary electrode LA2, so that the detection angle of the combination of the left arm main electrode LA and the second right arm auxiliary electrode RA2 and the combination of the second left arm auxiliary electrode LA2 and the right arm main electrode RA is 90°, which can cover the standard ECG axis range.

[0054] The right leg driving electrode RL is used to improve the common-mode interference of the system. The common-mode voltage on the human body surface is obtained through the right leg driving electrode RL, and then inputted back to the human body through negative feedback amplification, thereby offsetting the common-mode interference and fundamentally suppressing the common-mode voltage.

[0055] The housing structure is provided with a socket 4 and a lead wire 5. Figure 3 Socket 4 is used to transmit physiological data, using metal pin contacts or other methods to achieve signal connection. Lead wire 5, a flexible FPC cable, connects the ECG electrodes to socket 4 to transmit relevant physiological signals. Lead wire 5 is connected to the ECG electrodes using welding or conductive adhesive. Lead wire 5 is placed between the probe body 2 and the housing structure, which protects it. Lead wire 5 can also be manufactured using processes such as cable production and silver paste printing.

[0056] As can be seen from the above description, the detection probe provided by the present invention can achieve multiple functions through a single detection probe, with a high degree of integration, thus improving the user experience. Moreover, when the heart rate sensor malfunctions or ages, the mounting structure can be separated from the probe body, requiring only the corresponding parts to be replaced for repair. This overcomes the disadvantages of the prior art, such as the difficulty in maintenance, the need to replace the entire detection probe, and the resulting additional repair costs for the user, thereby facilitating maintenance and saving costs.

[0057] Figure 4 The diagram shows the working circuit of the central electrode of the detection probe provided by the present invention. In particular, the left arm main electrode LA, the first left arm auxiliary electrode LA1, the second left arm auxiliary electrode LA2, the right arm main electrode RA, the first right arm auxiliary electrode RA1 and the second right arm auxiliary electrode RA2 are respectively connected to corresponding buffer amplifiers.

[0058] Due to the different skin contact resistance and the weak ECG signal, if the ECG signal from the ECG electrode is directly amplified, the amplifier must have an extremely high input impedance, which is difficult to achieve in hardware with existing technology. By setting up a buffer amplifier, the signal and the differential amplifier input end are impedance matched, ensuring that the ECG signal is not distorted or interfered with.

[0059] The left arm main electrode LA and the right arm main electrode RA are respectively connected to the two input ends of the first differential amplifier 101 through corresponding buffer amplifiers (Buffer), and the output end of the first differential amplifier 101 is connected to the processing unit 107, forming a differential circuit of the left arm main electrode LA and the right arm main electrode RA to realize ECG signal differentiation, amplification and signal sampling.

[0060] The left arm main electrode LA and the first right arm auxiliary electrode RA1 are respectively connected to the two input ends of the second differential amplifier 102 through corresponding buffer amplifiers (Buffer), and the output end of the second differential amplifier 102 is connected to the processing unit 107, forming a differential circuit of the left arm main electrode LA and the first right arm auxiliary electrode RA1 to realize ECG signal differentiation, amplification and signal sampling.

[0061] The left arm main electrode LA and the second right arm auxiliary electrode RA2 are respectively connected to the two input ends of the third differential amplifier 103 through corresponding buffer amplifiers (Buffer). The output end of the third differential amplifier 103 is connected to the processing unit 107, forming a differential circuit of the left arm main electrode LA and the second right arm auxiliary electrode RA2 to realize ECG signal differentiation, amplification and signal sampling.

[0062] The first left arm auxiliary electrode LA1 and the right arm main electrode RA are respectively connected to the two input ends of the fourth differential amplifier 104 through corresponding buffer amplifiers (Buffer), and the output end of the fourth differential amplifier 104 is connected to the processing unit 107, forming a differential circuit of the first left arm auxiliary electrode LA1 and the right arm main electrode RA to realize ECG signal differentiation, amplification and signal sampling.

[0063] The second left arm auxiliary electrode LA2 and the right arm main electrode RA are respectively connected to the two input ends of the fifth differential amplifier 105 through corresponding buffer amplifiers (Buffer), and the output end of the fifth differential amplifier 105 is connected to the processing unit 107, forming a differential circuit of the second left arm auxiliary electrode LA2 and the right arm main electrode RA to realize ECG signal differentiation, amplification and signal sampling.

[0064] The left-arm main electrode LA and the right-arm main electrode RA are each connected to a sixth differential amplifier 106 via a corresponding buffer amplifier. The output of the sixth differential amplifier 106 is connected to the right-leg drive electrode RL, forming a right-leg drive circuit. The right-leg drive circuit obtains the common-mode voltage on the human body surface through the right-leg drive electrode RL and then transmits it back to the body through negative feedback amplification, thereby offsetting common-mode interference and fundamentally suppressing the common-mode voltage.

[0065] A differential amplifier consists of two inputs and one output. It amplifies the voltage difference between the two inputs at a fixed gain, thereby increasing the output power of the signal. It draws energy from a power supply to control the output signal's waveform to match the input signal, but with a larger amplitude.

[0066] The processing unit is used to determine the actual quality of the collected signals of each channel and decide to use the channel data with the best signal quality for relevant calculations.

[0067] The above circuit can achieve differential, amplification, and sampling of ECG signals from different electrode combinations. By combining two electrodes, signals at different angles to the ECG axis can be acquired to cover the standard ECG axis range, thus reducing user input. Signal quality is then assessed and the electrode combination with the best signal quality is used for relevant calculations. This automatically adjusts to the optimal ECG conduction direction, ensuring the maximum and optimal signal, ensuring stability and reliability throughout the monitoring process, and minimizing the impact of human interaction.

[0068] As another embodiment, the heart rate sensor can be replaced with a blood oxygen photoplethysmography sensor, which calculates the user's heart rate by detecting reflected light caused by the user's abdominal blood vessels. The heart rate sensor in the present invention can also be a variety of heart rate sensors used simultaneously, and the heart rate sensor type is not limited to ECG, blood oxygen, etc.

[0069] As another embodiment, Figure 6 As shown, the ECG electrodes include three electrodes arranged around the center of the active surface 3. These three electrodes are the left arm main electrode LA, the right leg drive electrode RL, and the right arm main electrode RA. The left arm main electrode LA and the right arm main electrode RA are fixed electrodes used to obtain ECG signals from the left and right arms of an adult, respectively.

[0070] As can be seen from this, the detection probe provided by the present invention can retain only fixed electrodes and acquire the user's heart rate by collecting the ECG signal from the fixed electrodes. During use, the detection probe can slightly adjust the probe electrode system based on the ECG signal amplitude, so that the angle between the lead axis and the ECG axis in three-dimensional space is small, thereby acquiring a positive, relatively large ECG signal. Obviously, in order to reduce user operation actions, avoid the impact of user operations on the monitoring structure, and to obtain a better signal, the preferred solution is to adopt the multi-electrode design scheme described in the above embodiment.

[0071] As another embodiment, the right leg drive electrode RL is used to improve the system's common-mode rejection capability and may be omitted in certain embodiments. For example, the ECG electrodes include six electrodes arranged around the center of the active surface 3, forming an angle with respect to the adult heart. The six ECG electrodes are the left arm main electrode LA, the first left arm secondary electrode LA1, the second left arm secondary electrode LA2, the second right arm secondary electrode RA2, the first right arm secondary electrode RA1, and the right arm main electrode RA.

[0072] In another embodiment, the ECG electrodes include five electrodes arranged around the center of the active surface 3, forming an angle with respect to the adult heart. These five electrodes are the left arm main electrode LA, the first left arm secondary electrode LA1, the right leg drive electrode RL, the first right arm secondary electrode RA1, and the right arm main electrode RA. The left and right arm secondary electrodes are referred to as regional electrodes. The number of regional electrodes can be varied based on practical needs and is not limited to two on each side. It can be one on each side, or multiple electrodes can be provided correspondingly on the left and right sides.

[0073] The present invention also provides an embodiment of a fetal monitor, which includes the detection probe in the above embodiment.

[0074] Embodiments of the present invention also provide a heart rate acquisition method, which is applied to a detection probe comprising a left-arm main electrode LA, a right-arm main electrode RA, and left-arm secondary electrodes and right-arm secondary electrodes. In this heart rate acquisition method, the specific number of left-arm secondary electrodes and right-arm secondary electrodes is not specifically limited and can be varied based on actual conditions.

[0075] like Figure 7 As shown, the heart rate acquisition method mainly includes:

[0076] Step S1: Acquire ECG data of each ECG electrode;

[0077] The acquisition of ECG data from each ECG electrode can be achieved by using an acquisition circuit in the prior art, or by using a method such as Figure 4 The working circuit shown is obtained.

[0078] Step S2: pairing the left arm main electrode LA and the left arm sub-electrode with the right arm main electrode RA and the right arm sub-electrode to form a plurality of electrode combinations, and performing differential processing on the plurality of electrode combinations to obtain differential signals.

[0079] The difference between the left arm auxiliary electrode and the right arm main electrode RA can obtain a signal different from the difference signal between the left arm main electrode LA and the right arm main electrode RA, and can obtain a signal at a different angle to the electrocardiographic axis.

[0080] Similarly, the difference between the left arm main electrode LA and the right arm secondary electrode can obtain a signal different from the difference signal between the left arm main electrode LA and the right arm main electrode RA, and can obtain a signal with a different angle to the electrocardiographic axis.

[0081] Therefore, by pairing the left arm main electrode LA and the left arm auxiliary electrode with the right arm main electrode RA and the right arm auxiliary electrode respectively, multiple electrode combinations with different angles between the lead axis and the ECG axis can be formed, thereby covering different ECG axis ranges to obtain more optional ECG signals.

[0082] Step S3: comparing differential signals of multiple electrode combinations;

[0083] Generally, the smaller the angle between the lead axis and the ECG axis in three-dimensional space, the more positive and relatively larger the ECG signal. Therefore, by comparing the signal quality, such as the strength and / or amplitude of each differential signal, the angle between the lead axis and the ECG axis in three-dimensional space for this electrode combination can be determined based on the signal quality.

[0084] Step S4: Process the electrode combination with the best signal quality to obtain the heart rate.

[0085] After comparison in step S3, the electrode combination with the best signal quality is obtained. The angle between the lead axis and the cardiac axis in three-dimensional space is minimized. Because the size of the ECG waveform picked up by the electrodes depends on the length of the projection of the average QRS vector (QRS cardiac axis) onto the lead axis, the best heart rate result is obtained using the electrode combination with the best signal quality.

[0086] How to design it? According to the placement of ECG electrodes, signals at different angles to the ECG axis can be obtained through paired comparison, and automatically adjusted to the optimal direction of ECG conduction to ensure the best signal, ensure the stability and reliability of the entire monitoring process, and reduce the impact of human operation.

[0087] Optionally, in some embodiments of the present invention, in order to improve the common mode rejection (CMR) performance of the system, the ECG electrodes further include a right leg driving electrode RL.

[0088] While ECG electrodes acquire ECG signals from the human body's surface, they also introduce environmental electrical signals, such as those from AC power, security systems, and radio frequency interference (RFI), to amplify and display the ECG signals. However, common-mode voltage does not provide any useful information about the heart and may actually affect measurement accuracy. Heart rate acquisition must be able to reject common-mode interference while responding to the target signal—the differential-mode ECG voltage. The ability to reject large common-mode signals in the presence of small differential signals is considered the system's common-mode rejection (CMR) performance.

[0089] The working principle of the right leg drive is to obtain the common-mode voltage on the human body surface through the right leg drive electrode RL, and then input it back to the human body through negative feedback amplification, thereby offsetting the common-mode interference and fundamentally suppressing the common-mode voltage.

[0090] Therefore, in order to improve the common mode rejection capability of the system, the heart rate acquisition method in this embodiment further includes:

[0091] The common mode voltage is obtained by driving the electrode RL of the right leg;

[0092] A suppression voltage matching the common mode voltage is delivered to the left-arm main electrode LA and the right-arm main electrode RA.

[0093] In some embodiments, the right leg drive electrode RL may be omitted.

[0094] For a detection probe including seven ECG electrodes, step S2 corresponds to an implementation method for seven ECG electrodes, including:

[0095] The left arm main electrode LA and the right arm main electrode RA are differentially processed to obtain a differential signal;

[0096] The left arm main electrode LA and the first right arm auxiliary electrode RA1 are differentially processed to obtain a differential signal;

[0097] The left arm main electrode LA and the second right arm auxiliary electrode RA2 are differentially processed to obtain a differential signal;

[0098] The first left arm auxiliary electrode LA1 and the right arm main electrode RA are differentially processed to obtain a differential signal;

[0099] The second left-arm auxiliary electrode LA2 and the right-arm main electrode RA are differentially processed to obtain a differential signal.

[0100] With this design, the first left arm auxiliary electrode LA1 is differentially connected to the right arm main electrode RA, and the second left arm auxiliary electrode LA2 is differentially connected to the right arm main electrode RA, so that a signal different from the differential signal between the left arm main electrode LA and the right arm main electrode RA can be obtained, and a signal with a different angle to the electrocardiographic axis can be obtained.

[0101] The difference between the left arm main electrode LA and the first right arm auxiliary electrode RA1 and the difference between the left arm main electrode LA and the second right arm auxiliary electrode RA2 can obtain a signal different from the difference signal between the left arm main electrode LA and the right arm main electrode RA, and can obtain a signal at a different angle to the electrocardiographic axis.

[0102] The lead axis formed by the left-arm main electrode LA and the second right-arm auxiliary electrode RA2 is perpendicular to the lead axis formed by the right-arm main electrode RA and the second left-arm auxiliary electrode LA2. This ensures that the detection angles for the combination of the left-arm main electrode LA and the second right-arm auxiliary electrode RA2, and the combination of the second left-arm auxiliary electrode LA2 and the right-arm main electrode RA, are 90°, covering the standard ECG axis range.

[0103] In this solution, the number of regional electrodes can be one on each side, or multiple. The corresponding heart rate acquisition method can be adaptively changed according to the above solution. The pairing processing method is the same as the above solution and will not be repeated in this article.

[0104] Optionally, in some embodiments of the present invention, acquiring the ECG signal of each ECG electrode further includes:

[0105] ECG data is pre-processed using filters to remove baseline drift, power frequency interference, and myoelectric interference, while also highlighting the QRS complex. The high-pass filter cutoff frequency is appropriately increased to suppress higher-frequency baseline drift, which is more likely to be introduced by this device.

[0106] The bottom line of the R-wave detection threshold is adjusted according to the signal amplitude information so that R-waves with small amplitudes can be detected smoothly.

[0107] Detect the heartbeat position to obtain the RR interval, and judge whether the ECG data is valid based on the RR interval.

[0108] Optionally, in some embodiments of the present invention, processing the electrode combination with the best signal quality to obtain the heart rate includes:

[0109] Identify possible motion artifact interference based on signal peak information;

[0110] In the interference segment, the peak interval detection method is used to select a more accurate R wave position based on the current heart rate baseline. The interference identification results are combined to correct the false detection caused by the peak detection in the interference segment.

[0111] An embodiment of the present invention further provides a heart rate acquisition device, comprising:

[0112] An acquisition module, used to acquire ECG data of each ECG electrode;

[0113] A differential module is used to pair the left arm main electrode and the left arm auxiliary electrode with the right arm main electrode and the right arm auxiliary electrode to form multiple electrode combinations, and perform differential processing on the multiple electrode combinations to obtain differential signals;

[0114] A comparison module for comparing differential signals of multiple electrode combinations;

[0115] The processing module processes the electrode combination with the best signal quality to obtain the heart rate.

[0116] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A detection probe, characterized in that: The invention comprises a probe body (2) and a mounting structure (1) detachably mounted on the probe body (2); the probe body (2) is an external uterine contraction pressure probe; the mounting structure (1) is a shell structure that can be directly sleeved on the outside of the probe body (2) and combined with the probe body (2) to form an integral body, and can be freely disassembled from the probe body (2) and separated from the probe body (2); the mounting structure (1) is provided with a heart rate sensor for heart rate detection, a socket (4) for data transmission, and a lead wire (5) connecting the heart rate sensor and the socket (4); The probe body (2) includes an inner side surface close to the user, the inner side surface includes a detection area that fits the user to realize the detection function of the probe body (2), the shell structure includes an active surface (3) that fits the probe body (2), the active surface (3) fits the user during detection, the heart rate sensor is arranged on the active surface (3), and the active surface (3) is provided with a through hole allowing the heart rate sensor to pass through and a hollow area corresponding to the detection area.

2. The detection probe according to claim 1, characterized in that: The mounting structure (1) is a shell structure that fits with the outer shell of the probe body (2).

3. The detection probe according to claim 2, characterized in that: The shell structure further comprises a connecting portion connected to the active surface (3), and the connecting portion is wrapped around the outer peripheral edge of the probe body (2).

4. The detection probe according to claim 3, characterized in that: The heart rate sensor is an electrocardiogram electrode arranged on the action surface (3).

5. The detection probe according to claim 4, characterized in that: The ECG electrodes include a left arm main electrode (LA) and a right arm main electrode (RA) for acquiring ECG signals of the left arm and the right arm respectively.

6. The detection probe according to claim 5, characterized in that: It also includes at least one left arm auxiliary electrode set at a set distance from the left arm main electrode (LA) for obtaining electrocardiographic signals in the left arm region, and at least one right arm auxiliary electrode set at a set distance from the right arm main electrode (RA) for obtaining electrocardiographic signals in the right arm region.

7. The detection probe according to claim 6, characterized in that: There are two left arm auxiliary electrodes and two right arm auxiliary electrodes, namely a first left arm auxiliary electrode (LA1) and a second left arm auxiliary electrode (LA2), and a first right arm auxiliary electrode (RA1) and a second right arm auxiliary electrode (RA2).

8. The detection probe according to claim 7, characterized in that: The lead axis formed by the left arm main electrode (LA) and the second right arm auxiliary electrode (RA2) is perpendicular to the lead axis formed by the right arm main electrode (RA) and the second left arm auxiliary electrode (LA2).

9. The detection probe according to any one of claims 4 to 8, characterized in that: Also included is a right leg drive electrode (RL) to improve the system's common-mode rejection.

10. The detection probe according to claim 3, characterized in that: The lead wire (5) is arranged between the active surface (3) and the probe body (2).

11. The detection probe according to claim 10, characterized in that: The lead wire (5) is a flexible FPC wire, or a conductive structure printed on the side of the housing structure facing the probe body (2).

12. The detection probe according to claim 1, characterized in that: The heart rate sensor is a blood oxygen photoplethysmography sensor.

13. A fetal monitor, characterized in that: The invention comprises the detection probe according to any one of claims 1 to 12.

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