GB2161572A - An improved coupling drive unit - Google Patents

Abstract

A coupling unit for transmitting rotary movement from a drive member 1, 4 outside a containment 3 to a driven member 2, 7 within the containment 3. The members 1, 2 are rotatably journalled in a housing 6, 9 with a link bar 10, supported by a gimbal ring 14, extending between diametrically opposed positions on the members 1, 2. A flexible diaphragm 13 which is clamped between first and second parts of the link bar 10 extends across the housing 6, 9 to isolate the driving member 1 from the driven member 2. <IMAGE>

Description

SPECIFICATION An improved coupling drive unit The present invention concerns a coupling unit for imparting positive rotary movement between driving and driven members.

When working with dangerous and toxic materials it is necessary to locate such materials in a sealed enclosure such as a glove box. It is frequently required to provide rotating worktools within the enclosure and this can be achieved by positioning a drive unit either inside or outside the enclosure. When the drive unit is located within the enclosure it will become contaminated by the atmosphere within the enclosure and this can create problems for maintenance. When the drive unit is located outside the enclosure it is necessary to provide a seal about the transmission passing through the wall of the enclosure. Problems can arise, especially under dry and dusty conditions, in providing an adequate seal about the transmission.

According to the present invention a coupling unit for imparting rotary movement comprises coaxial driving and driven members rotatably journalled in a housing, a link bar extending between diametrically opposed positions on the members, a gimbal within the housing to support the link bar and a flexible sealing diaphragm extending across the housing to isolate the driving member from the driven member, the diaphragm being clamped between first and second parts of the link bar.

During transmission between the driving and driven members the diaphragm flexes and changes shape but it is not subjected to rotary movement.

The invention will be described further, by way of example, with reference to the accompanying drawing which is a part cross-sectional view of an embodiment of a coupling unit according to the invention.

A coupling unit comprises a driving member 1 and a driven member 2 which are mounted in an opening in a wall 3, such as the wall of a glove box. The driving member 1, having an input drive shaft 4, is journalled by bearings 5 for rotation in a housing 6 and likewise the driven member 2, having an output drive shaft 7, is journalled by bearings 8 for rotation in a housing 9. The driving and driven members are connected by a link bar 10 which locates across a diameter, that is the end of the link bar at the driving member 1 is diametrically opposed to the end of the link bar at the driven member 2. Each end of the link bar terminates in a ball or sphere 11 which is located in a socket 1 2 in the respective driving and driven members. Rotation of the driving or driven member results in rotation of the other member due to the link bar 10 acting as a crank.

The link bar 10 is formed in two parts such that a flexible diaphragm 1 3 can be clamped therebetween with the periphery of the diaphragm being clamped between the housings 6 and 9. Normally, rotation of the driving and driven members causes the link bar 10 to rotate about its longitudinal axis. This rotation of the link bar is prevented by use of a gimbal support 14. As a result the diaphragm flexes or undulates during operation of the coupling unit and is not itself subjected to rotary movement.

1. A coupling unit for imparting rotary movement comprising coaxial driving and driven members rotatably journalled in a housing, a link bar extending between diametrically opposed positions on the members, a gimbal within the housing to support the link bar and a flexible sealing diaphragm extending across the housing to isolate the driving member from the driven member, the diaphragm being clamped between first and second parts of the link bar.

2. A coupling unit for imparting rotary movement substantially as herein described with reference to and as illustrated in the accompanying drawing.

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

Claims (2)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION An improved coupling drive unit The present invention concerns a coupling unit for imparting positive rotary movement between driving and driven members. When working with dangerous and toxic materials it is necessary to locate such materials in a sealed enclosure such as a glove box. It is frequently required to provide rotating worktools within the enclosure and this can be achieved by positioning a drive unit either inside or outside the enclosure. When the drive unit is located within the enclosure it will become contaminated by the atmosphere within the enclosure and this can create problems for maintenance. When the drive unit is located outside the enclosure it is necessary to provide a seal about the transmission passing through the wall of the enclosure. Problems can arise, especially under dry and dusty conditions, in providing an adequate seal about the transmission. According to the present invention a coupling unit for imparting rotary movement comprises coaxial driving and driven members rotatably journalled in a housing, a link bar extending between diametrically opposed positions on the members, a gimbal within the housing to support the link bar and a flexible sealing diaphragm extending across the housing to isolate the driving member from the driven member, the diaphragm being clamped between first and second parts of the link bar. During transmission between the driving and driven members the diaphragm flexes and changes shape but it is not subjected to rotary movement. The invention will be described further, by way of example, with reference to the accompanying drawing which is a part cross-sectional view of an embodiment of a coupling unit according to the invention. A coupling unit comprises a driving member 1 and a driven member 2 which are mounted in an opening in a wall 3, such as the wall of a glove box. The driving member 1, having an input drive shaft 4, is journalled by bearings 5 for rotation in a housing 6 and likewise the driven member 2, having an output drive shaft 7, is journalled by bearings 8 for rotation in a housing 9. The driving and driven members are connected by a link bar 10 which locates across a diameter, that is the end of the link bar at the driving member 1 is diametrically opposed to the end of the link bar at the driven member 2. Each end of the link bar terminates in a ball or sphere 11 which is located in a socket 1 2 in the respective driving and driven members. Rotation of the driving or driven member results in rotation of the other member due to the link bar 10 acting as a crank. The link bar 10 is formed in two parts such that a flexible diaphragm 1 3 can be clamped therebetween with the periphery of the diaphragm being clamped between the housings 6 and 9. Normally, rotation of the driving and driven members causes the link bar 10 to rotate about its longitudinal axis. This rotation of the link bar is prevented by use of a gimbal support 14. As a result the diaphragm flexes or undulates during operation of the coupling unit and is not itself subjected to rotary movement. CLAIMS

1. A coupling unit for imparting rotary movement comprising coaxial driving and driven members rotatably journalled in a housing, a link bar extending between diametrically opposed positions on the members, a gimbal within the housing to support the link bar and a flexible sealing diaphragm extending across the housing to isolate the driving member from the driven member, the diaphragm being clamped between first and second parts of the link bar.

2. A coupling unit for imparting rotary movement substantially as herein described with reference to and as illustrated in the accompanying drawing.