Abstract: Described are abrasive silica particles suitable for use in a dentifrice composition, the particles comprising particles of a first abrasive silica in an amount of at least 90 wt % relative to the total weight of the abrasive silica particles; and particles of a second abrasive silica in an amount of up to 10 wt % relative to the total weight of the abrasive silica particles, wherein the weight median particle diameter (d50) of the particles of the second abrasive silica is less than the weight median particle diameter (d50) of the particles of the first abrasive silica and from 15% to 70% of the d50 value of the particles of the first abrasive silica. Dentifrice compositions comprising such particles and methods of preparing such particles are also described.

Abstract: A locking mechanism for use in a quick hitch coupling device for coupling an attachment to a mechanical arm of, for example, an excavator. The invention is particularly but not exclusively concerned with a locking mechanism for a quick hitch coupling device comprising a safety system for automatically retaining the coupler in a locked arrangement.

Abstract: A control system for controlling the release of an accessory from any quick hitch coupler coupling the accessory to a hydraulically operable arm of a machine, operated by a pressurized hydraulic system. The control system can be used with a coupler for coupling an accessory to a dipper arm and a control system for such a coupler, such as a quick hitch coupler for coupling an accessory to a dipper arm of a back actor such as may be used by an earth working apparatus. The quick hitch coupler comprises a body member adapted for coupling to the dipper arm, a fixed engaging means mounted on the body member for engaging a first one of a pair of coupling pins mounted on the accessory, and a moveable engaging means mounted on the body member for engaging a second one of the pair of coupling pins of the accessory.

Abstract: A control system for controlling the release of an accessory from any quick hitch coupler coupling the accessory to a hydraulically operable arm of a machine, operated by a pressurized hydraulic system. The control system can be used with a coupler for coupling an accessory to a dipper arm and a control system for such a coupler, such as a quick hitch coupler for coupling an accessory to a dipper arm of a back actor such as may be used by an earth working apparatus. The quick hitch coupler comprises a body member adapted for coupling to the dipper arm, a fixed engaging means mounted on the body member for engaging a first one of a pair of coupling pins mounted on the accessory, and a moveable engaging means mounted on the body member for engaging a second one of the pair of coupling pins of the accessory.

Abstract: A coupler for coupling an accessory to a dipper arm and a control system for such a coupler. The invention concerns a quick hitch coupler for coupling an accessory to a dipper arm of a back actor such as may be used by an earth working apparatus. The quick hitch coupler comprises a body member adapted for coupling to the dipper arm, a fixed engaging means mounted on the body member for engaging a first one of a pair of coupling pins mounted on the accessory, and a moveable engaging means mounted on the body member for engaging a second one of the pair of coupling pins of the accessory. The invention also relates to a control system for controlling the release of an accessory from any quick hitch coupler coupling the accessory to a hydraulically operable arm of a machine, operated by a pressurized hydraulic system.

Abstract: A coupler for coupling an accessory to a dipper arm and a control system for such a coupler. The invention concerns a quick hitch coupler for coupling an accessory to a dipper arm of a back actor such as may be used by an earth working apparatus. The quick hitch coupler comprises a body member adapted for coupling to the dipper arm, a fixed engaging means mounted on the body member for engaging a first one of a pair of coupling pins mounted on the accessory, and a moveable engaging means mounted on the body member for engaging a second one of the pair of coupling pins of the accessory. The invention also relates to a control system for controlling the release of an accessory from any quick hitch coupler coupling the accessory to a hydraulically operable arm of a machine, operated by a pressurized hydraulic system.