An electric table and its anti-pinch detection sensor

Abstract

This utility model relates to an electric tabletop and its anti-pinch detection sensor, including a capacitance-to-digital conversion circuit, a processing module, and a detection device. The detection device is equipped with at least one anti-pinch electrode, which is located on the body and / or side of the linkage mechanism of the electric tabletop. The at least one anti-pinch electrode forms a capacitance sensor for detecting when a human body approaches or contacts the swing area of ​​the linkage. The capacitance-to-digital conversion circuit is coupled to the anti-pinch electrode to collect capacitance values. The processing module is coupled to the capacitance-to-digital conversion circuit to output an anti-pinch detection signal based on the capacitance values. The structure of this utility model can detect when a human body approaches or contacts the swing area of ​​the linkage, achieving a rapid response and exhibiting good reliability and detection sensitivity.

Description

Technical Field

[0001] This utility model relates to a folding table, and more particularly to an electric table and its anti-pinch detection sensor. Background Technology

[0002] Electrically adjustable tables are typically installed on the backrests of seats in vehicles, airplanes, high-speed trains, or high-end conference rooms, used for work or dining by people in the back rows. The core function of an electric table includes electric extension and retraction; a linkage mechanism transmits the driving force of an electric actuator through multiple joints, causing the table to retract or extend. Electric tables pose a risk of accidental pinching and require safety designs to prevent users (especially children) from being injured during table movement.

[0003] The search revealed that current anti-pinch mechanisms for electric tabletops primarily rely on detecting the motor's current or speed, such as:

[0004] CN222040307U proposes an electric table for the back of a car seat. A motor drives a pair of hinged rods to rotate the table relative to the back of the car seat. During the process, the anti-pinch detection function is achieved by detecting the motor's operating current and Hall effect value.

[0005] CN108859899B proposes a vehicle-mounted table control method, which includes analyzing the Hall signal of the drive motor during the process of folding or unfolding the small table, obtaining the motor speed information to determine whether it has touched an obstacle, thereby achieving anti-pinch detection.

[0006] This type of technology detects sudden changes in motor current or a decrease in speed. Protection is only triggered when the change reaches a threshold. There is a mechanical-electrical delay from clamping to stopping, which results in hysteresis. Utility Model Content

[0007] To address the shortcomings of existing technologies, an anti-pinch detection sensor for electric tabletops is proposed.

[0008] The electric tabletop anti-pinch detection sensor of this utility model includes a capacitance-to-digital conversion circuit, a processing module, and a detection device. The detection device is provided with at least one anti-pinch electrode, which is located on the body and / or side of the linkage mechanism of the electric tabletop. The at least one anti-pinch electrode forms a capacitance sensor for detecting when a human body approaches or contacts the swing area of ​​the linkage. The capacitance-to-digital conversion circuit is coupled to the anti-pinch electrode to collect the capacitance value. The processing module is coupled to the capacitance-to-digital conversion circuit and is used to output an anti-pinch detection signal based on the capacitance value.

[0009] The anti-pinch detection sensor of this utility model also includes the following auxiliary technical solutions:

[0010] The anti-pinch electrode is located on the table body of the electric table and is adjacent to the linkage mechanism.

[0011] The linkage mechanism has a first link for guiding the movement trajectory of the tabletop and a second link for driving the tabletop to move. Anti-pinch electrodes are arranged on the side wall of the first link facing the second link and / or the side wall of the second link facing the first link.

[0012] The corresponding connecting rod has a groove on its side wall, and the anti-pinch electrode is placed inside the groove.

[0013] The linkage mechanism is made of rigid insulating material; or the linkage mechanism is a metal conductor coupled to the ground, and the anti-pinch electrode is wrapped with an insulating layer.

[0014] Among them, the linkage mechanism is a metal conductor that is disconnected from the ground, and the conductor is reused as an anti-pinch electrode.

[0015] Among them, the anti-pinch electrode is a continuous strip electrode or discrete electrode segments arranged along the strip direction.

[0016] Wherein, the anti-pinch electrode is a self-capacitance electrode; and / or, there are at least two anti-pinch electrodes, and each anti-pinch electrode forms a mutual capacitance electrode pair.

[0017] The detection device is equipped with auxiliary electrodes, which are arranged along the edge of the electric table body to form fully enclosed or semi-enclosed electrodes. The capacitor-to-digital conversion circuit is coupled to the auxiliary electrodes.

[0018] Among them, the surface of the electric table is provided with load sensing electrodes for the status of the table being loaded, and the capacitor digital conversion circuit is coupled to the load sensing electrodes.

[0019] The load sensing electrode has several components, and the load sensing electrodes are arranged to form a discrete electrode array.

[0020] An electric table is also provided, including a table body, a linkage mechanism, and an electric actuator. The electric actuator drives the linkage mechanism to swing, thereby causing the table body to switch between a retracted position and an unfolded position. It also includes the aforementioned anti-pinch detection sensor.

[0021] The anti-pinch detection sensor structure of this utility model for electric tabletop, by means of the design of anti-pinch electrodes and the collection of capacitance by CDC, can achieve the following: detect the approach or contact of a human body with the swing area of ​​the linkage, achieving a response time much faster than that of current detection, avoiding lag problems; capacitive detection avoids the influence of motor efficiency fluctuations and mechanical dependence on the detection current, improving reliability; and combined with CDC to filter out stray capacitance, improving detection sensitivity. Attached Figure Description

[0022] Figure 1 A 3D structural diagram of the electric tabletop is provided.

[0023] Figure 2aA schematic diagram of a desktop arrangement of a single continuous self-electrode is given. Figure 2b A schematic diagram of a desktop arrangement for a single discrete electrode is given.

[0024] Figure 3a A schematic diagram of a desktop arrangement of two continuous electrodes forming a mutual capacitance electrode pair is given. Figure 3b A schematic diagram of the desktop arrangement of two discrete electrodes is given.

[0025] Figure 4a A schematic diagram of the arrangement of the anti-pinch electrodes on the relative motion surface of the first link is given. Figure 4b A schematic diagram of the anti-pinch electrode arrangement on the relative motion surface of the second link is given. Figure 4c A schematic diagram showing the arrangement of the anti-pinch electrodes on other surfaces of the first connecting rod is provided. Figure 4d A schematic diagram of the anti-pinch electrode arrangement on other surfaces of the second link is given.

[0026] Figure 5 A schematic diagram of the load sensing electrode arrangement is provided. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0028] See Figure 1 The electric table is placed on the back of a seat in a car, airplane, high-speed train or high-end conference room. It consists of a table body 1, a linkage mechanism 2 and an electric actuator (not shown). Its core is to drive the linkage mechanism 2 to swing through the electric actuator, so that the table body 1 switches between a folded (folded) position and an unfolded (used) position.

[0029] To achieve safety, the electric tabletop is equipped with an anti-pinch detection sensor. This sensor comprises a detection device and a circuit board. The circuit board houses a capacitance-to-digital converter (CDC) circuit, a processing module, and a switch array. These components are integrated into a single chip for miniaturization. The CDC circuit uses Δ-Σ modulation to directly convert the measured capacitance value into a digital value by repeatedly charging and discharging the capacitor and comparing it with a reference capacitance (see US Patent Number: 5,134,401), thus improving the measurement sensitivity to the 1ff level.

[0030] See Figure 2a , 3aAlternatively, in 4a, the detection device includes at least one anti-pinch electrode 3, located on the body and / or side of the linkage mechanism 2 of the electric tabletop. At least one anti-pinch electrode 3 forms a capacitive sensor for detecting when a human body approaches or contacts the swing area of ​​the linkage. A capacitance-to-digital conversion circuit is coupled to the anti-pinch electrode 3 via a switch array, and a processing module is coupled to the capacitance-to-digital conversion circuit. Due to the complexity of its motion, mechanical characteristics, and concealment, the linkage mechanism 2 is prone to dynamic clamping points. The mechanical gain amplifies the motor output force, resulting in a clamping force far exceeding the edge of the tabletop, posing a higher risk. The anti-pinch electrode 3 is located on the body and / or side of the linkage mechanism 2. When a human body approaches, the capacitance value of the anti-pinch electrode 3 changes. This change is linearly related to distance, thus identifying the human body's proximity to the swing area of ​​the linkage. A sudden change in capacitance occurs when the human body first contacts the anti-pinch electrode 3, which can be identified as a contact sensation. The processing module distinguishes between approach and contact based on the capacitance change of the anti-pinch electrode 3 and outputs an anti-pinch detection signal.

[0031] By utilizing the anti-pinch electrode design and the capacitance acquisition by the CDC, it is possible to: detect the approach or contact of a human body with the swing area of ​​the linkage, achieving a response time much faster than current detection and avoiding lag issues; capacitive detection avoids the influence of motor efficiency fluctuations and mechanical dependence on the detection current, improving reliability; and combined with CDC filtering to remove stray capacitance, improving detection sensitivity.

[0032] See Figure 2a , 2b In one exemplary embodiment, the anti-pinch electrode 3 is arranged on the table body 1 of the electric table and adjacent to the linkage mechanism 2. The table body 1 is a fixed or low-movement component, which ensures stable electrode wiring and eliminates the risk of frequent bending. At the same time, it monitors the capacitance change of the gap between the linkage and the table, and can cover the potential pinch area regardless of the swing phase of the linkage, thus avoiding blind spots.

[0033] See Figures 4a to 4d In another exemplary embodiment, the linkage mechanism 2 has a first link 21 for guiding the movement trajectory of the tabletop and a second link 22 for driving the tabletop movement. Electrodes are directly integrated into the surfaces of the first link 21 and / or the second link 22, enabling targeted monitoring of high-risk areas such as hinges or intersections to accurately locate pinch points, while simultaneously detecting human contact at close range, suitable for scenarios with extremely stringent anti-pinch response speed requirements. Preferably, see... Figure 4a , 4b Furthermore, the anti-pinch electrode 3 can be arranged on the side wall of the first link 21 facing the second link 22 and / or the side wall of the second link 22 facing the first link 21, that is, the surface where the two links move relative to each other. Compared with other side wall surfaces, it can accurately cover the area of ​​the most dangerous pinch point, monitor the capacitance change of the dynamic closed area in real time, and ensure that the anti-pinch is triggered before the finger or object enters the pinch point.

[0034] As a further improvement plan, see Figures 4a to 4d A groove is made on the side wall of the corresponding link, and the anti-pinch electrode 3 is placed inside the groove to provide physical protection for the electrode. The link mechanism 2 is made of rigid insulating material to enhance proximity detection capability; or the link mechanism 2 is made of a metal conductor coupled to the ground, and the anti-pinch electrode 3 is wrapped with an insulating layer. The metal conductor serves as a grounding shield electrode to optimize the electric field distribution of the anti-pinch electrode 3.

[0035] In another exemplary embodiment, the linkage mechanism 2 is configured as a metal conductor disconnected from the ground. This conductor is reused as an anti-pinch electrode 3, eliminating the need for electrode arrangement. While maintaining the original structural strength, the metal linkage participates in capacitance detection, thereby enhancing the detection coverage.

[0036] In this invention, the anti-pinch electrode 3 can be configured as a continuous strip electrode, such as... Figure 2a , 3a Single electrodes can be mounted or embedded in grooves in a single step, reducing assembly steps. Alternatively, the anti-pinch electrode 3 can also be configured as discrete electrode segments arranged along a strip direction, such as... Figure 2b , 3b This further differentiates between proximity and / or speed, while enhancing fault tolerance.

[0037] Figure 2a In this configuration, the anti-pinch electrode 3 serves as a self-capacitance electrode. The CDC includes an excitation signal line port (AEC), a mutual capacitance input signal line port (ACC), and a self-capacitance signal line port (SCA). When the anti-pinch electrode 3 functions as a self-capacitance electrode, it is selected to the SCA via a switch array to extend the detection distance. And / or, see [link to relevant documentation]. Figure 2b , 3a 3b, At least two anti-pinch electrodes 3 are provided, and each anti-pinch electrode 3 forms a mutual capacitance electrode pair. When the two pairs form a mutual capacitance electrode pair, one of them is selected to AEC through a switch array, and the other is selected to ACC, thereby enhancing the environmental anti-interference capability.

[0038] In another exemplary embodiment, the detection device is provided with an auxiliary electrode, which is arranged along the edge of the table body 1 of the electric table to form a fully enclosed or semi-enclosed electrode. For example, an electric wire is used to wrap around the edge of the table body. The capacitor digital conversion circuit is coupled with the auxiliary electrode to increase the anti-pinch detection of low-risk areas of the table, forming a redundant safety design with dual protection.

[0039] In another exemplary embodiment, see Figure 5The electric tabletop body 1 has load sensing electrodes 4 arranged on its surface. A capacitor-to-digital converter circuit is coupled to the load sensing electrodes 4 to detect the presence of objects on the tabletop. Furthermore, the load sensing electrodes 4 are arranged in a discrete electrode array to detect the position, distribution, and even shape of objects, achieving high-precision load sensing.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit the scope of protection of this utility model. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the essence and scope of the technical solutions of this utility model.

Claims

1. An anti-pinch detection sensor for an electric tabletop, characterized in that: Includes a capacitor-to-digital converter circuit, a processing module, and a detection device; The detection device is equipped with at least one anti-pinch electrode, which is located on the body and / or side of the linkage mechanism of the electric table. The at least one anti-pinch electrode forms a capacitive sensor for detecting when a human body approaches or contacts the swing area of ​​the linkage. The capacitance-to-digital conversion circuit is coupled with an anti-pinch electrode to acquire capacitance values; The processing module is coupled with a capacitor-to-digital converter circuit, which is used to output an anti-pinch detection signal based on the capacitance value.

2. The anti-pinch detection sensor according to claim 1, characterized in that: The anti-pinch electrode is arranged on the table body of the electric table and adjacent to the linkage mechanism.

3. The anti-pinch detection sensor according to claim 1, characterized in that: The linkage mechanism has a first link for guiding the movement trajectory of the tabletop and a second link for driving the tabletop to move. Anti-pinch electrodes are arranged on the side wall of the first link facing the second link, and / or the side wall of the second link facing the first link.

4. The anti-pinch detection sensor of claim 3, wherein: A groove is made on the side wall of the corresponding connecting rod, and the anti-pinch electrode is placed inside the groove.

5. The anti-pinch detection sensor according to claim 3 or 4, characterized in that: The linkage mechanism is made of rigid insulating material; or The linkage mechanism is a metal conductor coupled to the ground, and the anti-pinch electrode is wrapped with an insulating layer.

6. The anti-pinch detection sensor of claim 1, wherein: The linkage mechanism is a metal conductor that is disconnected from the ground, and the conductor is reused as the anti-pinch electrode.

7. The anti-pinch detection sensor of claim 1, wherein: The anti-pinch electrode is a continuous strip electrode or discrete electrode segments arranged along the strip direction.

8. The anti-pinch detection sensor according to claim 1, characterized in that: The anti-pinch electrode serves as a self-capacitance electrode. And / or, the anti-pinch electrode has at least two, and each anti-pinch electrode forms a mutual capacitance electrode pair.

9. The anti-pinch detection sensor according to claim 1, characterized in that: The detection device is equipped with an auxiliary electrode, which is arranged along the edge of the table body of the electric table to form a fully enclosed or semi-enclosed electrode. The capacitor-to-digital conversion circuit is coupled to the auxiliary electrode.

10. The anti-pinch detection sensor according to claim 1, characterized in that: The electric tabletop has load sensing electrodes arranged on its surface to indicate whether the tabletop is loaded with objects. A capacitor-to-digital converter circuit is coupled to the load sensing electrodes.

11. The anti-pinch detection sensor of claim 10, wherein: There are several load sensing electrodes, and the load sensing electrodes are arranged to form a discrete electrode array.

12. An electric tabletop, comprising a tabletop body, a linkage mechanism, and an electric actuator, wherein the electric actuator drives the linkage mechanism to swing, thereby causing the tabletop body to switch between a retracted position and an unfolded position, characterized in that: It also includes the anti-pinch detection sensor as described in any one of claims 1-11.

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