Abstract: A steering mechanism includes a handle with a tiller arm coupled to the handle via a flexible joint allowing relative movement of the handle about the tiller arm. A handle centering mechanism forming part of the steering mechanism includes a first end fixedly secured to the handle and a second end extending into a channel of the tiller arm. The second end compresses bumpers disposed on opposing sides of the second end. The bumpers urge the handle toward a neutral position wherein when a force is applied to move the handle away from a home position relative to the tiller arm, one of the compressed bumpers of the pair of compressed bumpers is further compressed. When the force is removed, the handle is returned to the home position by action of the pair of compressed bumpers. Preferably, the steering mechanism includes a torque sensing arrangement having a sensor and a magnet.

Abstract: A power steering assist system for a hand-steered pallet truck includes a joint assembly having a pivot joint, handle biasing mechanism, and a torque sensing arrangement. The pivot joint includes a pair of needle bearings and pivot pin disposed within a pivot block that provides a flexible connection between a handle and a tiller arm. The handle biasing mechanism includes a cantilevered beam spring and two cam rollers that resists an operator steering force applied to the handle and further, centers the handle with respect to the tiller arm after the force is released. The torque sensing arrangement includes a magnet and a non-contact magnetoresistive (MR) sensor that measures movement of the handle relative to the tiller arm which is used to determine operator steering intent, i.e., the amount of steering force applied to the handle. The MR sensor provides accurate torque measurements regardless of the angle of the tiller arm.

Abstract: A power steering assist system for a hand-steered pallet truck includes a joint assembly having a pivot joint, handle biasing mechanism, and a torque sensing arrangement. The pivot joint includes a pair of needle bearings and pivot pin disposed within a pivot block that provides a flexible connection between a handle and a tiller arm. The handle biasing mechanism includes a cantilevered beam spring and two cam rollers that resists an operator steering force applied to the handle and further, centers the handle with respect to the tiller arm after the force is released. The torque sensing arrangement includes a magnet and a non-contact magnetoresistive (MR) sensor that measures movement of the handle relative to the tiller arm which is used to determine operator steering intent, i.e., the amount of steering force applied to the handle. The MR sensor provides accurate torque measurements regardless of the angle of the tiller arm.

Abstract: A steering mechanism includes a handle with a tiller arm coupled to the handle via a flexible joint allowing relative movement of the handle about the tiller arm. A handle centering mechanism forming part of the steering mechanism includes a first end fixedly secured to the handle and a second end extending into a channel of the tiller arm. The second end compresses bumpers disposed on opposing sides of the second end. The bumpers urge the handle toward a neutral position wherein when a force is applied to move the handle away from a home position relative to the tiller arm, one of the compressed bumpers of the pair of compressed bumpers is further compressed. When the force is removed, the handle is returned to the home position by action of the pair of compressed bumpers. Preferably, the steering mechanism includes a torque sensing arrangement having a sensor and a magnet.