Constant force spring applied to the brake for remote surgery

Minimally invasive medical technology is used to reduce the number of foreign tissues that may be damaged during diagnosis or surgery, so as to reduce the recovery time, discomfort and adverse side effects of patients. The surgeon can operate the controller on the console to indirectly operate the instrument connected to the remotely operated actuator. The instrument can be disassembled from the remotely controlled actuator, so that the instrument can be disinfected separately and selected to be used as the instrument required for surgery. Combine. Instruments may be changed during surgery.

  Using remote instruments for surgery brings new challenges. One problem is to provide a remotely operated motor mechanism that supports a remotely operated actuator that can be positioned relative to a patient. These features are quite heavy and may weigh between 12 and 24 kilograms. The mechanism must be moved over the patient and carefully positioned. Therefore, it is necessary to balance the surgical instrument, the associated actuator, and the support structure so that the surgical instrument can be safely and easily positioned.

The constant force spring is made of stainless steel strip, so that when it is rolled up relative to being stretched, the spring will relax in a low stress state. When it unfolds, the restoring force mainly comes from the part close to the loosened spring coil. Specifically, the force comes from the region that transitions from a circle to a plane. The force does not come from the part of the drum that is fully unfolded or still winding. The resultant force is almost constant because the geometry of this area remains almost constant when the spring is deployed.

  As shown in Figure 2, the constant force spring 400 is connected to the vertical column 300 at the lower end 402 of the constant force spring. The constant force spring 400 is wound around the drum 404 supported by the upper end of the extensible support assembly 110. The constant force spring resists the gravity acting on the structure it supports, including the vertical column 300 and the surgical instrument. The constant force spring 400 provides a basically constant balance force for the support column 300 and the attachment structure, but its support load is more constant and different than what can be achieved by using the constant force spring alone. It is necessary to provide a balance force that can be compensated.

  The constant force spring device comprises a bracket, a drum rotatably supported by the bracket, and a constant force spring wound on the drum. The motor is fixed on the bracket to provide compensation force for the drum. The motor can be located within the internal volume of the drum. The control module can be connected to the motor to control the compensation force. The position sensor can be coupled to the control module. The compensation force can respond to the signal from the position sensor. The constant force spring can support the load and balance the gravity of the load. When the load approaches the end of the range of motion, the compensation force can be adjusted.

  From the initial design stage to the production and final assembly of  constant force spring, Qianye-Präzision can save customers product development time and find optimization solutions that exceed your expectations. There are no manufacturability constraints in product design, and the best product quality and best support and service can meet customers’ needs.Qianye-Präzision sincerely recommend our customers to consult with our R&D engineers at the early stage of product introduction and development.We assist in product design, development, and prototyping according to customer needs, so that you can find the best solution for your product to meet your application needs.