摘要:
The invention relates to an electrical circuit comprising a half-bridge (HB) having at least two transistors (T1, T2), a central connection (M) and a voltage supply, with which circuit an output voltage (U A ) which is switchable between at least two voltage levels can be set to a reference potential (U 0 ) by suitable switching of the at least two transistors (T1, T2). The electrical circuit has an auxiliary circuit (HS), which is connected to the central connection (M) of the half-bridge (HB) and has, for its part, at least two inductances (L2, L3), at least two transistors (T3, T4), at least two diodes (D1-D4) and at least two capacitances (C1-C6). The auxiliary circuit (HS) is in this case configured for the purpose of reducing power losses in the half-bridge (HB) in such a way that a current flow is generated by coordinated switching of at least one transistor (T3, T4) in the auxiliary circuit (HS) with switching operations of the transistors (T1, T2), said current flow enabling virtually current-free switching-off of the transistors (T1, T2) in the half-bridge (HB) and/or virtually voltage-free switching-on of the transistors (T1, T2) in the half-bridge (HB). The circuit is designed to bring about quick demagnetization of one of the at least two inductances (L2, L3) during operation of said circuit by virtue of the energy stored in the inductance (L2, L3) being transmitted into the voltage supply by opening of one of the transistors (T3, T4) in the auxiliary circuit (HS).
摘要:
The invention relates to a device and method for measuring the periphery of a body. To this end, the device comprises at least the following elements: A wire which has a known longitudinal section with a length LD; a position sensor (4) which is in active contact with the wire (5) such that a signal S is emitted as soon as the wire (5) exerts at least one predetermined tractive force Z on said position sensor (4); a drive device (6, 7) for tensioning the longitudinal section of the length LD of the wire (5) along the periphery (2) of the body (3). The drive device (6, 7) is connected to the position sensor (4) in such a way that the wire (5) is no longer tensioned when the signal S is emitted. The inventive device also comprises a path-measuring sensor which is in active contact with the drive device (6, 7) and which is provided for measuring the path WD over which the wire (5) travels when tensioned along the periphery (2) of the body (3) by said drive device (6, 7) so that the periphery (2) of the body (3) can be determined (150) from the length LD, from the path WD and from a device-dependent geometry factor G.
摘要:
An external force measurement unit 4 for measuring an external force fe applied to a spindle 10 includes a load cell 5 with a support ring 61, wherein a first flap 62 and a second flap 65 are arranged on the support ring 61, wherein the second flap 65 is arranged opposite to the first flap 62 on the support ring 61, wherein each flap is arranged in a radial direction towards the outside of the support ring 61, a first strain gauge 64, which is arranged on the first flap 62, and a second strain gauge 67, which is arranged on the second flap 65, an evaluation unit 14 for measuring the resistance of the first strain gauge 64 and the resistance of the second strain gauge 67, wherein the resistance of the first strain gauge 64 is measured separately from the resistance of the second strain gauge 67, a first bearing support 6 for taking up a first bearing 7 in a first bearing seat 68, wherein the first bearing 7 is adapted to take up a rotating spindle 10, wherein the evaluation unit 14 is configured to determine the external force fe based on the resistance of the first strain gauge 64 and the resistance of the second strain gauge 67.