Surgical power tool and actuation assembly therefor

A surgical power tool, comprising

• a housing;
• an actuation assembly mounted on the housing comprising:
• a force sensor configured to sense an actuation force;
• a sensor capsule mounted in an opening in the housing and holding the force sensor, the sensor capsule having a first cover section which is arranged proximal of the force sensor in a direction of force application and is coupled thereto in a force-transmitting manner;
• a mechanical damping member which is arranged outside of the first cover section in the direction of force application;
• a spring plate disposed between the mechanical damping member and the first cover section, wherein the spring plate is spaced apart from the first cover section in an undeflected state, and wherein application of the actuation force to the mechanical damping member deflects the spring plate toward the first cover section;
• and
• wherein the spring plate has an upper surface and a lower surface and a switching contact surface, both the upper and lower surfaces are coated with an electrically insulating material, with the switching contact surface free of the insulating material.

A surgical power tool, comprising:

• an elongated housing, having a first end and a second end, wherein a coupling for a tool element is provided at the first end of the housing and a battery pack is provided at the second end of the housing;
• an electric motor provided in an interior of the housing for an actuation of the tool element;
• a motor control circuit provided in the interior of the housing, wherein the motor control circuit is electrically connected to the electric motor and to the battery pack;
• at least one actuation assembly for an actuation-force-dependent control of the operation of the surgical power tool, the at least one actuation assembly being electrically connected to the motor control circuit and being arranged in an opening of the housing, the at least one actuation assembly comprising a sensor capsule and a force sensor arranged in the sensor capsule, the sensor capsule comprises a wall section, a cap base, and a cover section made of metal, wherein the force sensor is mounted on the metal cover section and is configured to detect a deformation of the metal cover section, and wherein the force sensor is hermetically sealed against sterilization media;
• a mechanical damping member which is arranged on the outside of the metal cover section in a direction of force application;
• a metal spring plate engaging a surface of the mechanical damping member, wherein the metal spring plate is located between the metal cover section and the mechanical clamping member and, in an undeflected state, is spaced apart from the cover section in the direction of force application;
• wherein the housing further comprises a collar, which is arranged around the opening to laterally surround the sensor capsule;
• and
• wherein the spring plate has an upper surface and a lower surface and a switching contact surface, both the upper and lower surfaces are coated with an electrically insulating material, with the switching contact surface free of the insulating material.

An actuation assembly for an actuation-force-dependent control of the operation of a surgical power tool, comprising:

• a force sensor capsule capable of being mounted in an opening of a housing of the power tool;
• a force sensor arranged in the force sensor capsule configured to sense the actuation force;
• the force sensor capsule having a metal first cover section which is arranged proximal of the force sensor in a direction of force application and is coupled thereto in a force-transmitting manner, wherein the force sensor is configured to detect a deformation of the metal first cover section and wherein the force sensor is hermetically sealed against sterilization media;
• a mechanical damping member which is arranged on an outer surface of the metal first cover section in the direction of force application, the mechanical damping member formed of an elastic material;
• a spring plate disposed between the mechanical damping member and the first cover section, wherein the spring plate is spaced apart from the first cover section in an undeflected state, and wherein application of the actuation force to the mechanical damping member deflects the spring plate toward the first cover section;
• wherein the spring plate comprises a switching contact, wherein application of the actuation force deflects the switching contact into electrical contact with the metal first cover section, and wherein the electrical contact of the switching contact with the metal first cover section switches an electric switching circuit;
• and
• wherein the spring plate has an upper surface and a lower surface and a switching contact surface, both the upper and lower surfaces are coated with an electrically insulating material, with the switching contact surface free of the insulating material.