38results about How to "Significant change in resistance" patented technology

The invention provides a flexible piezoresistive touch sensor array and a preparation method thereof. The sensor array comprises N*N separated piezoresistive layers and a coplanar electrode layer. The piezoresistive layers are arranged on the coplanar electrode layer. Each piezoresistive layer comprises an upper finger pressing layer, a middle sensitive layer and a bottom sensitive layer, wherein the three layers are each provided with a micro pyramid; the coplanar electrode layer comprises a polymer electrode substrate and N*N gold electrode pairs located on the polymer electrode substrate. The piezoresistive layers adopt polymer films with the micro pyramid, and due to the three-layer structure, the sensitivity of the sensor at the low-voltage region can be greatly improved. In addition, in order to overcome the defect that a traditional touch sensor is large in crosstalk due to a sandwiched structure, the coplanar electrode layer is adopted, all electrodes are located on the same plane, each piezoresistive layer is attached to the corresponding electrode pair, the piezoresistive units are completely separated, and the sensitivity and anti-interference capacity of the sensor are effectively improved.

The invention provides a knee presser foot lifting device of a sewing machine, which belongs to the technical field of garment manufacturing equipment. The utility model solves the technical problems such as the easy damage of the existing knee presser foot lifting device. The sewing machine includes a pressing rod and a small presser foot arranged at the lower end of the pressing rod. A pressing spring is sleeved on the pressing rod. The presser foot lifting device includes a lifting front lever and a lifting rod which drives the swinging of the lifting rod. The end is connected with a lifting rear lever, and the presser foot lifting device also includes an electromagnet, a knee control hinge shaft and a knee rest plate. A varistor is connected, a limit frame is also connected to the knee control hinge shaft, and a jacking assembly is arranged between the limit frame and the lifting lever; the end of the jacking assembly is connected with the end of the lifting lever. The knee presser foot lifting device in the present invention is more labor-saving and less prone to damage.

The invention discloses a microwave detection element, which is composed of a sheet-like pinning layer, an insulating layer, a free layer and a heavy metal layer which are stacked in sequence. The upper magnetic pinning layer is annular, and the free layer, the insulating layer and the heavy metal layer The shape of the layer is set to circle. Among them: Dzyaloshinskii–Moriya interaction can be generated between the heavy metal layer material and the free layer material, the magnetic moment in the pinned layer is arranged in the vertical direction, and due to the Dzyaloshinskii–Moriya interaction, the magnetic moment in the free layer is arranged as a magnetic moment. skyrmion state. In the microwave detection element of the present invention, when a microwave current signal is input, the size of the magnetic skyrmions will change periodically. Due to the existence of the tunnel magnetoresistance effect, the resistance value of the element will also change periodically, which is different from the input signal. The microwave current coupling produces a DC signal, enabling microwave detection. The present invention can greatly improve the sensitivity value.

The invention belongs to the field of functional polymer hydrogels, and particularly relates to a stretchable, compressible and antifreeze organic hydrogel electrolyte, a preparation method and applications. The organic hydrogel electrolyte provided by the present invention is formed from methacryloylethylsulfobetaine, acrylamide, and dimethyl sulfoxide and water as solvents through radical initiation polymerization, and the cross-linked network is doped with soybean protein. The organic hydrogel electrolyte provided by the invention has a maximum fracture strain of up to 762.5%, can still recover to the original state after repeated 500% tensile or 80% compressive strain, and has excellent mechanical properties; the room temperature conductivity can reach 37.5mS ·cm ‑1 , at ‑20°C, the charge-discharge time is still 13s, so it has good low-temperature electrical properties, and can achieve the technical effect of using hydrogel electrolyte as a supercapacitor electrolyte; it has strain sensitivity, and can realize hydrogel electrolyte as a stable The technical effect of the sensor material.

The invention relates to flexible intelligent wearable equipment. The equipment comprises a humidity sensing module, a measuring module, a processing module and a display module, the moisture sensingmodule is composed of blended yarn, the blended yarn is mainly composed of stainless steel fiber and fiber A, and the fiber A is polyester fiber, cotton fiber or polyester-cotton blended fiber; the humidity sensing module is used for resistance change in response to humidity change, and is a 1+1 rib stitch or a weft plain stitch or a interlock stitch which is formed by weaving the blended yarn through a flat knitting machine with the device number of E10-16 and contains stainless steel fiber; the content of the stainless steel fiber in the humidity sensing module is 10-50 g / m<2>; the measuringmodule is used for measuring the resistance of the humidity sensing module; the processing module is used for processing the resistance of the humidity sensing module to obtain the humidity; the display module is used for displaying the humidity. The humidity sensing module in the flexible intelligent wearable equipment is small in size, soft in texture, convenient to wear and excellent in wearability; the precision is high when the humidity is measured; the measurement process saves time and labor.

The invention discloses an overvoltage warning device and method based on a pressure sensor and an electrochromic device. The overvoltage warning device comprises a control circuit, a signal input line, a trigger pressure adjustment knob, a voltage display area, a delay adjustment knob, a delay trigger switch, an output line and an electrochromic device, wherein the control circuit is provided with a pressure sensor, a first slide rheostat, a voltmeter, an NPN triode, a second slide rheostat and a switch; the signal input line is extracted from two ends of the pressure sensor; the trigger pressure adjustment knob is connected with the first slide rheostat; the voltage display area is connected with the voltmeter; the delay adjustment knob is connected with the second slide rheostat; the delay trigger switch is connected with the switch; the output line is extracted from an output end; and the electrochromic device is connected with two ends of the output line. When the overvoltage warning device is triggered by pressure, the output voltage is immediately reversed, and the electrochromic device is enabled to change in color; and when the pressure is below a trigger value, the outputvoltage is enabled to be reversed again, and the electrochromic device is enabled to return back to be original color. The overvoltage warning device is simpler and more stable in control circuit, less in consumed electric energy, safer and more environment-friendly and has a good warning effect.

The invention discloses a piezoresistive type flexible tactile sensor with double-layer fastener type micro-bosses. The sensor is formed by stacking a semi-spherical protrusion, an upper-layer micro-boss array, a stretchable electrode array, a flexible pressure-sensitive array and a lower-layer micro-boss array structure which are arranged sequentially from top to bottom, wherein the flexible pressure-sensitive array is composed of a linear graphene pattern array and a flexible thin-film substrate; and the stretchable electrode array is composed of row and column strip-shaped electrodes and circular insulating barriers between the row and column strip-shaped electrodes. The stretchable electrode array is tightly attached to the flexible pressure-sensitive array; and square pins are arranged on the two sides of each linear graphene pattern, and are connected with the row and column strip-shaped electrodes respectively to form a closed loop. The double-layer fastener type micro-bosses are adopted to convert an external force effect on the tactile sensor into tensile deformation of the linear graphene patterns in the flexible pressure-sensitive array, so that the resistance change ofthe pressure-sensitive array is more obvious, and the sensitivity of the tactile sensor is improved; and meanwhile, the flexible design of the tactile sensor is realized by adopting a conductive composite material.