Curtis Instruments Inc.

Yale Materials Handling Corporation

Eugene P Finger

Bernard W Jalbert

Thomas A Penkalski

Edward M Marwell

Eugene A Sands

In one preferred embodiment of the invention, a method of restoring charge to a battery operating with a predetermined terminal voltage, including: determining an expected rate of degradation of a plate or plates of a battery in terms of decrease of capacity per unit time and temperature of operation of the battery to determine a degree of degradation of capacity of the battery; and providing sufficient charge to the battery to restore a predetermined degree of the capacity of the battery. In another preferred embodiment of the invention, a method of diagnosing state of health of a battery, including: restoring a theoretical amount of charge to a partially depleted battery; and examining how the battery responded to the step of restoring a theoretical amount of charge to the partially depleted battery to determine the state of health of the battery.

Method of diagnosing the state of health of a battery

In a preferred embodiment, a method of condition monitoring of an opportunity charged battery, including: determining length of time the battery has been off-line; determining whether charging of the battery has occurred during the length of time; if step (b) results in a determination that the charging of the battery has occurred, determining degree of charging of the battery occurring during the length of time; and if step (b) results in a determination that charging of the battery has occurred, resetting a condition monitor associated with the battery to reflect the degree of charging of the battery.

Condition monitoring of opportunity charged batteries

Method of battery charge restoration based on estimated battery plate deterioration and/or based on battery state of health

In a preferred embodiment, a system of physical measurement and display of a parameter, including: accepting an input signal representative of a value of the parameter, the input signal having an arbitrary shape and amplitude; and displaying the value of the parameter in an arbitrary shape; including the use of analog and digital circuitry and nonvolatile memory.

Compact, low-cost semiconductor device for receiving arbitrary input parameters and driving selected display devices, and methods

In a preferred embodiment, a sequential high-rate battery charger for charging a battery having a plurality of cell units, the battery charger including a current source; an apparatus to selectively sequentially connect each of the plurality of cell units to the high current source; and an apparatus to sequentially provide high current from the high current source to each of the plurality of cell units for a first selected period of time.

Sequential high-rate charging of battery cells

In a preferred embodiment, a metering system for measuring and indicating the state of charge of an electrical storage battery, including: apparatus for storing a numerical value indicative of the state of charge of the battery and for providing an output voltage signal representative thereof; apparatus for detecting the terminal voltage of the battery, coupled to the apparatus for storing, and being operable to generate a function of the battery terminal voltage which is a substantially proportional fraction of the terminal voltage and to provide an input to the apparatus for storing if the function is below a threshold variable reference voltage signal; apparatus for receiving the output voltage signal and for generating the variable reference voltage signal therefrom, the variable reference voltage signal being lowered as a function of the output voltage signal as the output voltage signal indicates progressively lower states of charge; and apparatus for measuring the level of current drawn from the battery and adjusting the apparatus for receiving and generating, in proportion to the current level, such that the variable reference voltage signal will be greater or lesser depending on the current level.

Method and means for adjusting battery monitor based on rate of current

A method and apparatus for measuring operations data which uses a commercially available digital multimeter (DMM) as the data receiving and display device. In one preferred embodiment, for example, basic operations data is transduced to digital form and then coded with a width modulator. The width modulated data may represent, for example, total elapsed time or total counts of a measured operation. The full-scale range of the data is encoded as frequency. A technician reads the frequency of the data signal with the DMM to determine the full-scale range of the data and then reads percent-of-range with the DMM as duty cycle. For multiple operations data, peak voltage is used as a parameter identifier. Alternatively, the value of the parameter being measured, the full-scale range, and the parameter identifier may be encoded as any combination of frequency, peak voltage, or duty cycle. In a further aspect, one parameter, preferably frequency, may be encoded with additional information, such as data site and data channel. In another aspect, the data stream is amplitude modulated to indicate selected alarm levels.

Data encodement and reading method and apparatus

A proximity switch including an inductor having an actuator rod movable in proximity thereto to affect the inductance thereof. An electrical pulse of relatively short duration is applied to the inductor and the current from the inductor is measured at a selected time interval after the initiation of the pulse. When a selected value of the current is exceeded, the switch is triggered. A plurality of inductors may be sequentially interrogated by one electronic circuit, thus requiring low power and affording smooth operation. Calibration of the trigger point is accomplished electronically after mechanical installation, thus inherently compensating for mechanical tolerances and proximity effects.

Inductive proximity switch means and method

A motion sensor which includes, in a basic embodiment, two sensing elements of any type disposed so as to detect the relative passing thereby of perturbations. The sensing elements are disposed so that they are offset with respect to the perturbations, such that the sensing elements cannot both be activated simultaneously. When one sensing element is activated, thus indicating motion, timing means starts counting and, if the other sensing element is activated within a predetermined length of time, the sensor infers that purposeful motion has been detected and may, for example, activate a power steering assist unit. The spacing of the perturbations determines the minimum degree of motion required for the motion sensor to provide an output and the timing mechanism determines how rapidly that degree of motion must occur for the motion sensor to provide the output. Thus, the spacing and time parameters may be set so that purposeful motion may be discriminated from random motion such as vibration. The sensing elements may be photodetectors, microswitches, pressure sensors, reed switches, or conductive, inductive, or capacitive proximity sensors, or of any other type. The corresponding perturbations may be arrayed on either a rotating or a linearly moving member.

Motion sensor useful for power assisted steering systems

A reader device, preferably implemented in solid-state form, is provided as a separate element for connecting to a so-called cumulative operations measurement system. Such a system is, for example, concerned with the measurement of elapsed time, especially in determining how long a particular piece of apparatus may have been functioning; or, on the other hand, measuring events such as the number of times a particular piece of apparatus has been turned on without regard to the elapsed time. The reader device is preferably provided with its own source of power, or it can rely on the power source contained within the operations measurement system. The reader device is designed on a conservative basis such that it carefully monitors the frequency involved in the measurement system, and determines whether the measurement system is operating at the correct frequency; furthermore, whether there are low-voltage battery conditions present in the system; a special filter arrangement is provided such that a very low data rate can be employed.

Solid-state reader device for a cumulative operations measurement system

The monitor is a circuit including an integrator for storing a state-of-charge measurement and a charge signal channel and a separate discharge signal channel both arranged for connection to receive a battery terminal voltage signal. The charge signal channel is operable in response to a battery terminal voltage signal above a charge threshold function voltage to produce a charge output signal to change the integrated measurement in the integrator in a first direction to indicate an increased charge. The discharge signal channel is operable in response to a battery terminal voltage signal below a discharge threshold function voltage to produce a discharge output signal to change the integrated measurement in the integrator in a second direction to indicate a decreased charge. Both the charge and discharge threshold function voltages are functions of the stored integrator state-of-charge measurement.

Bidirectional battery state-of-charge monitor

The indicator is especially useful for an industrial truck with a steerable wheel which can be turned through a steering arc of as much as one hundred eighty degrees. The indicator includes a potentiometer mechanically coupled to be rotated in synchronism with the steering rotation of the steerable wheel, and a multiple voltage threshold detector circuit connected to receive the variable voltage from the potentiometer and operable to provide one out of N discrete output signals in response to potentiometer voltages which have predetermined voltage level relationships to the respective voltage thresholds. At least N discrete indicator lamps are arranged in an array for indicating steerable wheel direction, and the indicator lamps are connected to receive the discrete output signals from the multiple voltage threshold detection circuit for indicating travel direction.

Steerable wheel direction indicator

The system includes a battery state-of-charge monitoring circuit which is operable to produce a signal change when there is a change in the battery charge from an acceptable charge to a substantially reduced charge. The signal change from the monitor is connected to control a lock-out relay to disable a control circuit for a load controller for battery powered equipment which is to be locked out. A current detecting device is connected to detect the presence of current in the control circuit of the controller and is connected to hold off the lock-out operation of the lock-out relay while current is flowing in the control circuit to thereby assure that the lock-out of the load occurs after a normal interruption of the load control circuit.

Synchronous load lock-out control system for battery powered equipment

The system accurately measures a summation of the operations when an operating voltage is present. The system includes a capacitor charged by a supply voltage and a volatile memory register connected to receive the operating voltage signals to be measured and operable to store those signals as a measure of operations. A nonvolatile memory register is provided having stages corresponding to the stages of the volatile memory register. A store sequencing means is connected to be powered by the energy stored in the capacitor when the supply voltage is removed to transfer the count stored in the volatile memory register into the nonvolatile memory register. A means is provided for detecting when the supply voltage is applied, with a recall sequencing means operable in response thereto to transfer the count stored in the nonvolatile memory register into the volatile memory register.

Solid-state cumulative operations measurement system

The system includes a digital integrator having a plurality of digital stages operable to store a numerical value in binary digital form which is indicative of state of charge. A switching circuit is provided for generating a series of voltage pulses on a single output line with each pulse corresponding in length to the binary digital value stored in the integrator to provide a time based resultant indication of the stored binary digital value. A filtering means is included to provide a substantially smooth analog output voltage having an amplitude corresponding to the summation of the pulses. The system preferably includes a delayed high voltage reset feature to set the integrator to a full charge state in response to voltage levels accompanying charging of the battery.

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Brewster, NY, United States of America

Eugene P Finger