Tachometer and rotor identification apparatus for centrifuges
AssigneeBeckman Instruments, Inc.
InventorDennis Durbin
Life of this patent
Estimating the term…
Abstract
An apparatus for determining the actual speed and maximum safe speed of a centrifuge rotor. A single circular array of equally spaced coding elements of two clearly distinguishable types is attached to the rotor. A single detector responsive to the coding elements produces an output signal that varies in accordance with both the number and type of the coding elements. A first circuit network is responsive to the number of coding elements encountered per unit time, without regard to type, to produce an actual speed or tachometer signal. A second circuit network is responsive to the number of coding elements of each type encountered during each revolution of the rotor, without regard to the speed thereof, to produce a rotor identification signal that is indicative of the maximum safe speed of the rotor.
Claims29
An apparatus for determining the actual speed and the maximum safe speed of a centrifuge rotor, comprising:
- (a) a plurality of coding elements of first and second types attached to the rotor, the number of coding elements of each type defining a code which indicates the maximum safe speed of the rotor,
- (b) a detector responsive to said coding elements for generating an output signal that varies in accordance with the number and type of said coding elements,
- (c) first signal processing means responsive to the number of coding elements for generating a signal indicative of the actual speed of the rotor, and
- (d) second signal processing means responsive to the types of the coding elements for generating a signal indicative of the maximum safe speed of the rotor.
An apparatus for determining the actual speed and the maximum safe speed of a centrifugal rotor, comprising:
- (a) a circular array of magnets attached to the rotor, the north south orientations of the magnets in said array defining a code indicative of the maximum safe speed of the rotor,
- (b) a magnetic detector responsive to said magnets for generating an output signal which is indicative of the magnetic orientations of said magnets,
- (c) signal generating means responsive to said output signal for generating an actual speed signal indicative of the actual speed of the rotor, and
- (d) decoding means responsive to said output signal for decoding said code to determine the maximum safe speed of the rotor.
An apparatus for determining the actual speed and the maximum safe speed of a centrifuge rotor, comprising:
- (a) a circular array of magnets attached to the rotor, the north south orientations of the magnets in said array defining a code indicative of the maximum safe speed of the rotor,
- (b) a magnetic detector responsive to said magnets for generating an output signal which is indicative of the magnetic orientations of the magnets.
- (c) first means for separating the output signal into a north signal indicating the detection of north oriented magnets and a south signal indicating the detection of south oriented magnets,
- (d) second means connected to said first means for generating an actual speed signal that varies in accordance with the detection of north or south oriented magnets.
- (e) north counting means connected to receive the north signal for counting the number of north oriented magnets in the array,
- (f) south counting means connected to receive the south signal for counting the number of such oriented magnets in the array, and
- (g) programmable control means connected to the north and sourth counting means for determining the maximum safe speed of the rotor from the number of north and south oriented magnets.
Dependencies are inferred from the claim text.