Rotary atomisers

A rotary atomiser spindle arrangement comprising a rotary atomiser spindle having a shaft which is journaled for rotation in a main body of the rotary atomiser spindle and a bell cup releasably mounted on the shaft, the bell cup having a bell portion for spraying media during rotation in use and a mounting portion via which the bell cup is mounted on the shaft, the shaft and mounting portion of the bell cup comprising respective complimentary taper portions which form an interference fit with each other when the bell cup is mounted on the shaft so locating in the bell cup in relation to the shaft, the mounting portion further comprising an elongate portion provided with at least one retention engaging portion at a distal end of the mounting portion,

• wherein the rotary atomiser spindle arrangement comprises a bell cup retention arrangement having retention biasing means for urging the complimentary taper portions against one another when the bell cup and shaft are at a first relative rotational position with respect to one another whilst the bell cup retention arrangement allows at least demounting of the bell cup from the shaft when the bell cup and shaft are at a second relative rotational position with respect to one another, and the bell cup retention arrangement comprises latching means for latching the bell cup and shaft in the first relative rotational position,
• wherein the latching means comprises a latch member and a latch biasing means for biasing the latch member towards a latching position, the latch member having at least one detent portion for engaging with a respective complimentary latch engaging portion when the latch member is in the latching position for resisting relative rotation of the shaft and bell cup away from the first relative rotational position,
• wherein the bell cup retention arrangement comprises a retention assembly carried on one of the shaft and the bell cup, and comprising the retention biasing means as well as a sleeve having at least one first engaging portion for acting on the other of the shaft and the bell cup under action of the retention biasing means for urging the complimentary taper portions against one another,
• wherein the at least one first engaging portion is provided on an axially facing surface at an end of the sleeve distal from the bell portion of the bell cup and in which the latch member comprises the sleeve, the detent portion is provided on said distal axially facing surface of the sleeve and the complimentary latch engaging portion is provided on said other of the shaft and the bell cup, the sleeve further comprising an internal bore through the length of the sleeve,
• wherein the elongate portion of the mounting position passes through said bore during mounting such that the at least one retention engaging portion engages with the first engaging portion,
• wherein the sleeve comprises a camming surface on said distal axially facing surface of the sleeve, the camming surface leading to the at least one detent portion, and
• wherein as the bell cup is rotated relative to the shaft towards and away from the first relative rotational position, the complimentary latch engaging portion rides over the camming surface towards and away, respectively, from the detent portion, the camming surface being inclined such that when the bell cup is rotated from the second relative position to the first relative position the latch engaging portion rides over the camming surface towards the detent portion such that the bell cup is drawn towards the shaft until the complimentary taper portions are in contact, further rotation drives the sleeve towards the bell cup against the action of the retention biasing means, thus enabling the latching position to be reached.

A rotary atomiser spindle arrangement comprising a rotary atomiser spindle having a shaft which is journaled for rotation in a main body of the rotary atomiser spindle and a bell cup releasably mounted on the shaft, the bell cup having a bell portion for spraying media during rotation in use and a mounting portion via which the bell cup is mounted on the shaft, the shaft and mounting portion of the bell cup comprising respective complimentary taper portions which form an interference fit with each other when the bell cup is mounted on the shaft so locating in the bell cup in relation to the shaft,

• wherein the rotary atomiser spindle arrangement comprises a bell cup retention arrangement having retention biasing means for urging the complimentary taper portions against one another when the bell cup and shaft are at a first relative rotational position with respect to one another whilst the bell cup retention arrangement allows at least demounting of the bell cup from the shaft when the bell cup and shaft are at a second relative rotational position with respect to one another, and the bell cup retention arrangement comprises latching means for latching the bell cup and shaft in the first relative rotational position,
• wherein the latching means comprises a latch member and a latch biasing means for biasing the latch member towards a latching position, the latch member having at least one detent portion for engaging with a respective complimentary latch engaging portion when the latch member is in the latching position for resisting relative rotation of the shaft and bell cup away from the first relative rotational position,
• wherein the bell cup retention arrangement comprises a retention assembly carried on one of the shaft and the bell cup, and comprising the retention biasing means as well as a sleeve having at least one first engaging portion for acting on the other of the shaft and the bell cup under action of the retention biasing means for urging the complimentary taper portions against one another and in which the latch member comprises the sleeve, the detent portion is provided on the sleeve and the complimentary latch engaging portion is provided on said other of the shaft and the bell cup, and
• wherein the retention biasing means and sleeve are positioned inside the shaft.

A rotary atomiser spindle arrangement comprising a rotary atomiser spindle having a shaft which is journaled for rotation in a main body of the rotary atomiser spindle and a bell cup releasably mounted on the shaft, the bell cup having a bell portion for spraying media during rotation in use and a mounting portion via which the bell cup is mounted on the shaft, the shaft and mounting portion of the bell cup comprising respective complimentary taper portions which form an interference fit with each other when the bell cup is mounted on the shaft so locating the bell cup in relation to the shaft, the mounting portion further comprising a latch engaging portion,

• wherein the rotary atomiser spindle arrangement comprises a bell cup retention arrangement having retention biasing means for urging the complimentary taper portions against one another when the bell cup and shaft are at a first relative rotational position with respect to one another whilst the bell cup retention arrangement allows at least demounting of the bell cup from the shaft when the bell cup and shaft are at a second relative rotational position with respect to one another,
• wherein the bell cup retention arrangement comprises a retention assembly carried on one of the shaft and the bell cup comprising the retention biasing means and a sleeve having a camming surface on an axially facing surface, said axially facing surface being distal from the bell portion of the bell cup, the camming surface leading to at least one detent portion, and
• wherein as the bell cup is rotated relative to the shaft towards and away from the first relative rotational position, the latch engaging portion rides over the camming surface towards and away, respectively, from the detent portion, the camming surface being inclined such that when the bell cup is rotated from the second relative position to the first relative position the latch engaging portion rides over the camming surface towards the detent portion such that the bell cup is drawn towards the shaft until the complimentary taper portions are in contact and further rotation drives the sleeve towards the bell cup against the action of the retention biasing means, thus enabling a latch position to be reached.