GB2029931A - Rollers - Google Patents

Abstract

A roller for a belt conveyor has a spacer member 12 which is formed of two halves 15, 16 of semi-circular cross- section and press-fitted into a tube 10 in order to prevent corrosive gases and air from entering the space between the bearings 13 due to temperature changes. The bearings 13 and seals 14 are housed in the spacer member halves 15, 16 which are joined by a rubber or foamed plastics packing 17. If desired, the spacer member 12 may taper from the middle towards each end and the tube 10 deformed to follow the tapers. <IMAGE>

Description

SPECIFICATION A roller for a belt conveyor This invention concerns a roller for a belt conveyor.

With conventional rollers, comprising a tube mounted by bearings for rotation about a shaft, there is a large internal free space between the bearings. Thermal variations inside the roller between when it is running and stationary result in expansion and contraction of the enclosed air. This can suck in humid and corrosive gases and air causing rust which can penetrate into the bearings.

Also lubricant will leave the bearings and collect in the free space if special seals are not provided inboard of the bearings.

The invention provides a roller for a belt conveyor which roller comprises a tube, a shaft extending co-axially through the tube, a spacer member pushfitted in the bore of the tube and encircling the shaft, bearings spaced apart by and fixed in recesses in the spacer member, and seals for the bearings located adjacent to the bearings, which bearings are fixed between the spacer member and shaft and support the spacer member and tube for rotation about the shaft, the spacer member extending around the bearings and seals and comprising two longitudinally extending halves of semi-circular cross-section.

The spacer member may extend on both axial sides of each bearing and have a smaller internal diameter outboard of each bearing than the external diameter of the bearing.

A resiliently deformable material may be disposed between the longitudinally extending facing planar surfaces of the two halves of the spacer member.

At least one end of the spacer member may decrease in external diameter in the direction from the middle of the spacer member to that end.

An embodiment of the invention will now be described by way of example, reference being made to the accompanying drawings, of which Figure 1 is part of a longitudinal section of a roller; and Figure 2 is a cross-section of a spacer member on a larger scale.

Referring to Figure 1,the roller shown comprises a tube 10 with a shaft 11 extending co-axially through it. A spacer member 12 is push-fitted in the bore of the tube 10 and encircles the shaft 11. Bearings 13 (of which only one is shown) are spaced apart by and fixed in recesses in the spacer member 12. There are at least two and preferably more bearings 13 and they are depicted as ball-bearings. A seal 14 for the bearing 13 is located adjacent to the bearing. The bearings 13 are fixed between the shaft 11 and spacer member 12 and support the spacer member and tube 10 for rotation about the shaft. The spacer member 12 extends around the bearings 13 between the tube 10 and shaft 11 and also on both axial sides, and has a smaller internal diameter inboard and outboard of the bearing than the external diameter of the bearing.

The spacer member 12 comprises two longitudinally extending halves 15 and 16 each of semi-circular cross-section which substantially fill the available space in the roller.

Referring in particular to Figure 2, a soft resiliently deformable material 17 for example, rubber or foamed plastics, is disposed between the longitudin ally extending facing and planer surfaces of the two halves 15 and 16 of the spacer member 12. This facilitates assembly of the roller in which the mate rial 17 is compressed when the two halves 15 and 16 and the seals 14 and bearings 13 are fitted into the tube 10.

As a further aid in assembling the roller, at least one end of the spacer member 12 decreases in external diameter in the direction from the middle of the spacer member to that end. If both ends of the spacer member 12 taper inwardly towards the end, and the tube 10 is bent to follow the taper of the spacer member when it is fitted in the bore of the tube, then relative axial movement between the tube and the spacer member is prevented.

The spacer member 12 need not extend outboard i.e. on the outer axial side of the bearing 13, and may extend inboard i.e. on the inner axial side of the bearing, and around the bearing.

1. Arollerfora beltconveyorwhich roller comprises a tube, a shaft extending co-axially through the tube, a spacer member push-fitted in the bore of the tube and encircling the shaft, bearings spaced apart by and fixed in recesses in the spacer member, and seals for the bearings located adjacent to the bearings, which bearings are fixed between the spacer member and shaft and support the spacer member and tube for rotation about the shaft, the spacer member extending around the bearings and seals and comprising two longitudinally extending halves of semi-circular cross-section.

2. A roller as claimed in claim 1, wherein the spacer member extended on both axial sides of each bearing and has a smaller internal diameter out board of each bearing than the external diameter of the bearing.

3. A roller as claimed in claim 1 or 2, wherein a resiliently deformable material is disposed between the longitudinally extending facing planar surfaces of the two halves of the spacer member.

4. A roller as claimed in claim 1,2 or 3, wherein at least one end of the spacer member decreases in external diameter in the direction from the middle of the spacer member to that end.

5. A roller for a belt conveyor substantially as herein described with reference to and as shown in the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (5)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A roller for a belt conveyor This invention concerns a roller for a belt conveyor. With conventional rollers, comprising a tube mounted by bearings for rotation about a shaft, there is a large internal free space between the bearings. Thermal variations inside the roller between when it is running and stationary result in expansion and contraction of the enclosed air. This can suck in humid and corrosive gases and air causing rust which can penetrate into the bearings. Also lubricant will leave the bearings and collect in the free space if special seals are not provided inboard of the bearings. The invention provides a roller for a belt conveyor which roller comprises a tube, a shaft extending co-axially through the tube, a spacer member pushfitted in the bore of the tube and encircling the shaft, bearings spaced apart by and fixed in recesses in the spacer member, and seals for the bearings located adjacent to the bearings, which bearings are fixed between the spacer member and shaft and support the spacer member and tube for rotation about the shaft, the spacer member extending around the bearings and seals and comprising two longitudinally extending halves of semi-circular cross-section. The spacer member may extend on both axial sides of each bearing and have a smaller internal diameter outboard of each bearing than the external diameter of the bearing. A resiliently deformable material may be disposed between the longitudinally extending facing planar surfaces of the two halves of the spacer member. At least one end of the spacer member may decrease in external diameter in the direction from the middle of the spacer member to that end. An embodiment of the invention will now be described by way of example, reference being made to the accompanying drawings, of which Figure 1 is part of a longitudinal section of a roller; and Figure 2 is a cross-section of a spacer member on a larger scale. Referring to Figure 1,the roller shown comprises a tube 10 with a shaft 11 extending co-axially through it. A spacer member 12 is push-fitted in the bore of the tube 10 and encircles the shaft 11. Bearings 13 (of which only one is shown) are spaced apart by and fixed in recesses in the spacer member 12. There are at least two and preferably more bearings 13 and they are depicted as ball-bearings. A seal 14 for the bearing 13 is located adjacent to the bearing. The bearings 13 are fixed between the shaft 11 and spacer member 12 and support the spacer member and tube 10 for rotation about the shaft. The spacer member 12 extends around the bearings 13 between the tube 10 and shaft 11 and also on both axial sides, and has a smaller internal diameter inboard and outboard of the bearing than the external diameter of the bearing. The spacer member 12 comprises two longitudinally extending halves 15 and 16 each of semi-circular cross-section which substantially fill the available space in the roller. Referring in particular to Figure 2, a soft resiliently deformable material 17 for example, rubber or foamed plastics, is disposed between the longitudin ally extending facing and planer surfaces of the two halves 15 and 16 of the spacer member 12. This facilitates assembly of the roller in which the mate rial 17 is compressed when the two halves 15 and 16 and the seals 14 and bearings 13 are fitted into the tube 10. As a further aid in assembling the roller, at least one end of the spacer member 12 decreases in external diameter in the direction from the middle of the spacer member to that end. If both ends of the spacer member 12 taper inwardly towards the end, and the tube 10 is bent to follow the taper of the spacer member when it is fitted in the bore of the tube, then relative axial movement between the tube and the spacer member is prevented. The spacer member 12 need not extend outboard i.e. on the outer axial side of the bearing 13, and may extend inboard i.e. on the inner axial side of the bearing, and around the bearing. CLAIMS

1. Arollerfora beltconveyorwhich roller comprises a tube, a shaft extending co-axially through the tube, a spacer member push-fitted in the bore of the tube and encircling the shaft, bearings spaced apart by and fixed in recesses in the spacer member, and seals for the bearings located adjacent to the bearings, which bearings are fixed between the spacer member and shaft and support the spacer member and tube for rotation about the shaft, the spacer member extending around the bearings and seals and comprising two longitudinally extending halves of semi-circular cross-section.

2. A roller as claimed in claim 1, wherein the spacer member extended on both axial sides of each bearing and has a smaller internal diameter out board of each bearing than the external diameter of the bearing.

3. A roller as claimed in claim 1 or 2, wherein a resiliently deformable material is disposed between the longitudinally extending facing planar surfaces of the two halves of the spacer member.

4. A roller as claimed in claim 1,2 or 3, wherein at least one end of the spacer member decreases in external diameter in the direction from the middle of the spacer member to that end.

5. A roller for a belt conveyor substantially as herein described with reference to and as shown in the accompanying drawings.