Abstract: A quick-releasing linear actuator suitable for electric hospital beds includes a motor, a transmission device, a clutch device and a pulling arm device. With the pulling of the pulling arm of the pulling arm device, a clutch and a clutch base of the clutch device can be disengaged, such that the screw of the transmission device will not be impeded by the worm gear. When a force is exerted to the telescopic rod of the transmission device, the screw can rotate by itself to rapidly lower the telescopic rod, thereby to achieve the rapid releasing of the hospital beds.

Abstract: A photoelectric control structure for a linear transmission device, including a mount, a transmission gear mounted on the mount and coupled to a motor, a photoelectric circuit board mounted on the mount and having a phototransistor and an infrared light emitting diode which controls the phototransistor, a light chopper turned by the transmission gear to intermittently block light from the light emitting diode toward the phototransistor, and a chopper cover fastened to the mount and covering the light chopper and the photoelectric circuit board for protection, wherein when the motor is started, the transmission gear is driven to turn the light chopper, causing light to intermittently pass through to the phototransistor, and therefore the infrared light emitting diode intermittently drives the phototransistor to send a pulse wave signal to the signal input terminal of a satellite antenna allocator.

Abstract: A photo chopper circuit consisting of a photo chopper, an overvoltage detection/control device, a power switch, and a protective diode for connection to the power supply line, voltage detection line, and ground terminal of a satellite antenna allocator, wherein if the photo chopper is erroneously connected to the voltage line of the satellite antenna allocator for motor drive or the power supply line of the satellite antenna allocator, the overvoltage detection/control device is turned on to switch off the power switch or, the protective diode reverses flow of voltage to protect the photo chopper.

Abstract: A physical traction machine has two U-shaped brackets connected in parallel with a telescopic rod vertically attached thereto at the middle for carrying a traction device to pull a patient's neck or waist for relieving pressure from cervical vertebrae or lumbar vertebrae. An adjusting device is attached to the first U-shaped bracket for adjusting its width. Another adjusting device is attached to the second U-shaped bracket for adjusting its height.