Abstract: The subject brake test apparatus operates in conjunction with a vehicle having a source of power, a traction motor controllably connected to the power source and to at least one vehicle wheel, and a vehicle brake associated with at least one vehicle wheel. An actuator controllably engages and disengages the vehicle brake in response to receiving respective brake control signals, and a transducer produces wheel rotation signals in response to rotation of at least one of the vehicle wheels. A processor controllably delivers a brake engaging signal to the actuator and engages the vehicle brake. A predetermined amount of power from the power source is delivered to the traction motor for a predetermined period of time.
Abstract: Information related to the rotary angular position of a steerable wheel portion of an electric vehicle is required for proper control of the vehicle and especially for differential control of the driven wheels of the vehicle. Available rotary position encoders are expensive, prone to damage in an industrial environment, and sensitive to misalignment between the encoder components. The instant apparatus provides a simple and durable rotary position encoder having a plurality of sensors positioned on a first mounting member and a plurality of sensible members positioned on a second mounting member. The apparatus is digital in design and the particular location and arrangement of the sensors and sensible members advantageously compensates for overtravel and misalignment of the encoder components.
February 21, 1984
Date of Patent:
January 28, 1986
Wayne T. Wiblin, Grant C. Melocik, Edward V. Leskovec, William Pickering
Abstract: Controlling arrangements of the type used for aligning a load engaging assembly with a load to be lifted tend to be bulky, costly, unable to accurately position the load engaging assembly with the load to be lifted, and unable to accommodate different types of load supporting structures. A controlling arrangement having a signal assembly having first and second spaced apart portions is provided. The first portion is adapted to deliver a first signal and receive a reflection of the first signal and the second portion is adapted to deliver a second signal and to receive a reflection of the first signal. A single sensing device is adapted to receive the reflected signals and a selecting device controls the operation of the first and second signal assembly portions. Therefore, the problems of bulk, cost, inaccuracy and flexibility are eliminated. The controlling arrangement is particularly suited for use on a material handling vehicle.
Abstract: Single pedal vehicle speed and direction controls are advantageously applied in industrial vehicles. Available pedals are prone to damage in an industrial environment and require multiple discrete pedal portions for various pedal functions. The instant apparatus provides a simple and durable foot pedal having a unitary pad including first and second integral moveable members and respective sealed switchable members. The pad is advantageously of one piece molded rubber construction and includes first and second resilient portions, each having a curvilinear connecting portion and an intermittent substantially solid connecting portion. The switchable members include respective sealed membrane switches, each having first and second spaced apart electrically conductive contact surfaces.
Abstract: Power assisted steering systems are commonly used on industrial vehicles such as industrial lift trucks. Advantageously, the output of such systems should be responsive to vehicle speed and the systems should be energy efficient. The subject power steering control system includes processor means for receiving a steering demand signal and a speed control signal, producing a high fluid flow rate signal in response to receiving the steering demand signal and to the speed control signal representing a vehicle speed less than or equal to a predetermined vehicle speed, producing a low fluid flow rate signal in response to receiving the steering demand signal and to the speed control signal representing a vehicle speed greater than the predetermined speed, and producing an idle fluid flow rate signal in response to failing to receive the steering demand signal.
Abstract: Apparatus is provided for controlling increases in the speed of a motor, including a transducer coupled to an accelerator pedal, that generates digital numbers representing motor speed commands, a data processor for receiving the speed commands, generating motor speed limit signals in response to the digital numbers and delivering the limit signals to a controllable circuit for supplying power to the motor. The limit signals are delivered in response to time and the magnitude of the speed commands.
Abstract: The mast assembly for a standard lift truck includes a lift system having a centrally-disposed hydraulic cylinder and a pair of chains mounted on the cylinder to selectively raise and lower a movable upright assembly on a fixed upright assembly and a carriage on the movable upright assembly. This arrangement impairs the forward field of vision of the operator. The mast assembly (11) of this invention overcomes this problem by securing opposite ends of a chain (17) to laterally space uprights (13,14) of a fixed upright assembly (12), entraining the chain (17) under at least one chain guide (20) mounted on a lower end of a movable upright assembly (15), and engaging the chain with a hydraulic cylinder (22) to selectively raise and lower the movable upright assembly (15) on the fixed upright assembly (12).
Abstract: A control system (28) is provided for controlling the supply of power to a motor (12) having an armature (34) and a plugging diode (38) connected across the armature (34), including a circuit (14) for producing direction command signals, a circuit (98) for generating digital motor power command signals, a circuit (16) for sensing a plugging condition and generating a plug signal, a microprocessor (46) for generating one of a plurality of pulse trains during typical plugging conditions and for automatically overriding the generation of the one pulse train and generating other of the plurality of pulse trains during special plugging conditions. By automatically providing the override feature during the special plugging conditions, the disadvantage of manual override in prior control systems is obviated.
Abstract: A retention assembly is disclosed for use with an elongated flexible member (22) such as the lift chain used in a lift truck (10). This assembly consists of a first member (30) affixed to the carriage (28) and having an irregular surface (32) corresponding to the irregular surface (26) of the chain. A second clamping member (34) also has an irregular surface (36) for gripping the lift chain (32) with the first member (30). Fastening members (42 and 44) fix the second member (34) to the first member (30) with the lift chain (22) therebetween.
Abstract: Container handlers comprise a plurality of double-acting hydraulic cylinders to effect the various side shift, twist lock, tilt, height adjustment, and spread modes of operation. Separate control valves and hoses, entrained over the mast assembly having the attachment thereon, are required to effect such functions selectively. This invention is directed to a programmed electro-hydraulic control circuit when reduces the required number of hoses to two and provides a non-complex system which can be operated expeditiously.
Abstract: This invention relates to a suspended seat assembly (10) which eliminates the problems of excessive elevational movement and limited field of use, harsh ride, inability to accommodate a broad range of occupant weights, bulkiness, wear and premature failure, and difficult adjustment. The suspended seat assembly has a seat frame (12), a support frame (14), a connecting apparatus (42) which pivotally connects the seat frame (12) to the support frame (14) and permits movement of the seat frame (12) between a first position (38) above the support frame (14), past the support frame (14), to a second position (40) below the support frame (14), a tie apparatus (66) which maintains the seat frame (12) at a preselected attitude relative to the support frame (14), and a biasing arrangement (74) for biasing the connecting apparatus (42) and urging the seat frame (12) to the first position (38).
January 10, 1983
Date of Patent:
June 4, 1985
Lawrence A. Liljequist, John E. Wible, Richard A. Schwehr
Abstract: The invention pertains to an apparatus (10) for diagnosing and displaying the condition of various components in an electro-mechanical vehicle or other system. The apparatus (10) includes command signal producing devices (12), control signal receiving devices (14), and means (16) for delivering control signals to the receiving devices (14) in response to receiving the produced command signals. The means (16) includes means (128) for receiving diagnostic command signals and displaying a predetermined diagnostic code in response to receiving a predetermined command signal. Both in-service and out-of-service diagnostics are provided for and a minimum of equipment external to the apparatus (10) is required, thus making the system both efficient and low in cost.
Abstract: The invention pertains to a control system (46) for controlling the supply of power to a motor (12) to produce plugging electrical braking and current limit control, including a circuit (60) for controlling the direction of energization of the motor (12), a circuit (88) for generating digital numbers representing command motor speeds, a circuit (14) for generating a data signal representing a plugging condition, a programmable data processor (18) for generating pulse trains in dependence on the plugging condition, and a power transistor element (40) for coupling power to the motor (12) in response to the pulse trains. By using state-of-the-art digital, integrated circuit and software technology, prior, essentially linear or discrete component technology, which is relatively unreliable, expensive and slow, need not be used.
Abstract: Apparatus (10) is provided for controlling current through a motor (12), including a circuit (14) for generating motor speed command data, a circuit (26) for generating a control signal in response to a maximum value of current through the motor (12), a programmable data processor (72) for generating pulse trains in response to the command data, and a controllable supplying circuit (18) for coupling and decoupling power to the motor (12) in response to the pulse trains and for decoupling power to the motor (12) in response to the control signal independent of the pulse trains. By decoupling power from the motor (12) independent of the control produced by the data processor (72), the current limit is achieved even if the data processor (72) malfunctions, contrary to prior apparatus.
Abstract: Apparatus (10) for monitors and protects a plurality of contactor coils (14A-E) and coil drivers (16A-E) from damage owing to short circuits, and prevents the concurrent energization of more than a preselected number of the coils (14A-E). Included is a monitor (84) for sensing the total current flowing through the plurality of coils (14A-E) and supplying a variable current signal in response to a magnitude of the sensed total current, and a control (85) for receiving the variable current signal and controlling the energization of the coils (14A-E) in response to the magnitude of the current signal. By monitoring and controlling the energization of the plurality of coils (14A-E) damage due to excessive current flow through the coils (14A-E) is avoided and the number of concurrently energized coils (14A-E) is limited to the preselected number.
Abstract: This invention relates to a pump arrangement (54) for use in a linear fluid operated device having a reciprocating piston (14) separating a first active fluid chamber (30) and a second chamber (32) which eliminates the problem associated with fluid leakage buildup developing in the second chamber. The pump arrangement (54) is connected to the reciprocating piston (14) and pumps leakage fluid present in the second chamber (32) from the second chamber (32) and into the first chamber (30) in response to a force of a preselected minimum magnitude being applied to the pump arrangement (54). Thus, the problems of inefficient linear fluid operated device operation, reduced piston stroke length, external fluid leakage, and erratic piston travel speed are eliminated. The pump arrangement (54) is particularly suited for use in a single acting linear hydraulic jack (12) such as used on a material handling vehicle.
Abstract: An apparatus (10) for controlling the supply of power from a power source (12) to a motor (14,14'). The apparatus (10) has a controllable switch (20,20') for coupling power to the motor (14,14') responsive to a pulse train, a circuit (22,22') for converting the voltage applied to the motor (14,14') to a logic signal, a line contactor (26) for connecting and disconnecting the power source (12) to and from the motor (14,14'), and a microprocessor (60) for generating the pulse train and controlling the line contactor (26) to disconnect and connect the power source (12) from and to the motor (14,14') in response to the presence and absence of the logic signal, respectively. By sensing short circuits and discontinuing the supply of power in response to the short circuit, a runaway motor speed condition can be avoided, and by using a microprocessor, the present invention is highly reliable, fast, durable, and cost-effective.
Abstract: A hood (18) and a control device (38) mounted on a vehicle (10) adjacent the hood (18) obstructs access to a source of motive power (24) of the vehicle (10), interferes with removal of the source of motive power (24) resulting in damage to the control device (38) and hood (18), and requires additional steps be taken to prepare the vehicle (10) for servicing. A pivotal hood arrangement (16) having a hood (18) and a control device (38) mounted on the hood (18) is provided. The control device (38) is movable with the hood into an opening (48) in the vehicle (10) to permit maximum movement of the hood (18) to an uncovering position (28). A closing device (52) is provided for closing the opening (48) and a retainer (74) is provided for holding the closing device (52) at a closed position (59). Thus, the problems of access, interference, damage and additional steps are eliminated. The pivotal hood arrangement (16) is particularly suited for use in a lift truck (10).
Abstract: Special attachments mounted on a carriage assembly of a lift truck normally require one or more hydraulic cylinders to effect the various work tasks. A plurality of flexible hoses are normally routed over a mast assembly of the lift truck and are suitably connected to the cylinders to communicate pressurized hydraulic fluid. Such routing arrangements normally impair the forward visibility of the operator and do not always provide for a compact and protected disposition of the hoses on the mast assembly. The routing arrangement (24) of this invention includes a plurality of sheaves (28) and brackets (33) for mounting and guiding loop portions (25) of flexible hoses (21) on a movable upright assembly (14) in vertically spaced and closely compacted relationship to permit vertical movements of the movable upright assembly (14) relative to the hoses (21).
Abstract: A lift mast for industrial trucks includes a stationary upright having a movable upright mounted thereon and a lift jack interconnected between the uprights. A bracket member is secured to a cylinder of the lift jack and is further secured to the stationary upright along with at least one elastomeric bushing that will allow the cylinder to move slightly relative to the stationary upright.