초록 ▼

A driven seal assembly is provided for a shaft rotated by a motor disposed in a motor housing and having a seal housing adjacent to the motor housing through which the shaft extends. A first rotary seal is frictionally fit on the shaft adjacent the first stationary seal seat. A second rotary seal is

A driven seal assembly is provided for a shaft rotated by a motor disposed in a motor housing and having a seal housing adjacent to the motor housing through which the shaft extends. A first rotary seal is frictionally fit on the shaft adjacent the first stationary seal seat. A second rotary seal is frictionally fit on the shaft adjacent a second stationary seal seat. A spring surrounds the shaft and provides bi-directional axial forces on the first and second rotary seals against the first and second stationary seal seats. A positive drive mechanism is mounted on the shaft between the first and second rotary seals in a driving, mating relationship therewith and includes a first driving element in driving engagement with the first rotary seal and a second driving element in driving engagement with the second rotary seal.

대표청구항 ▼

What is claimed is: 1. In a driven seal assembly for a shaft rotated by a motor disposed in a motor housing and having a seal housing adjacent to the motor housing through which the shaft extends, there being a first stationary seal seat mounted on the shaft and secured in a bore of the seal housin

What is claimed is: 1. In a driven seal assembly for a shaft rotated by a motor disposed in a motor housing and having a seal housing adjacent to the motor housing through which the shaft extends, there being a first stationary seal seat mounted on the shaft and secured in a bore of the seal housing, a first rotary seal frictionally fit on the shaft adjacent the first stationary seal seat, a second stationary seal seat mounted on the shaft and secured in a bore of the motor housing, a second rotary seal frictionally fit on the shaft adjacent the second stationary seal seat, the improvement wherein: a positive drive mechanism is mounted on the shaft between the first and second rotary seals in a driving, mating relationship therewith and includes a first driving element in driving engagement with the first rotary seal and a second driving element in driving engagement with the second rotary seal; and a spring is placed in compression between the first and second driving elements to provide a bi-directional axial force on the first and second driving elements to press the first and second rotary seals against the first and second stationary seal seats, whereby the first and second driving elements are drivingly connected together independently of the spring for rotation with the shaft by a driving arrangement engaged by the first and second rotary seals. 2. The improvement of claim 1, wherein the positive drive mechanism includes a third driving element fixed to the shaft between the first and second driving elements and encircled by the spring. 3. The improvement of claim 2, wherein the third driving element is connected by pins to the first and second driving elements. 4. The improvement of claim 1, wherein the spring encircles axially extending portions of the first and second driving elements. 5. The improvement of claim 4, wherein the spring has opposite ends engaged against portions of the first and second driving elements extending radially from the axially extending portions. 6. The improvement of claim 1, wherein the first and second driving elements are formed with non-circular cavities for receiving mating non-circular portions of the first and second rotary seals. 7. The improvement of claim 6, wherein the shaft passes freely through the cavities of the first and second driving elements. 8. A driven seal assembly for a shaft rotated by a motor disposed in a motor housing and having a seal housing adjacent the motor through which the shaft extends, the driven seal assembly comprising: a first stationary seal seat mounted on the shaft and secured in a bore of the seal housing; a first rotary seal frictionally fit on the shaft adjacent the first stationary seal seat; a first rotor driver mounted on the shaft in mating relationship with the first rotary seal; a second stationary seal seat mounted on the shaft and secured in a bore.of the motor housing; a second rotary seal frictionally fit on the shaft adjacent the second stationary seal seat; a second rotor driver mounted on the shaft in mating relationship with the second rotary seal; a set collar attached to the shaft for rotation therewith between the first and second rotor drivers and drivingly connected thereto; and a spring of substantially constant diameter surrounding the set collar in spaced relationship therefrom and placed in compression between the first and second rotor drivers, whereby the set collar is drivingly connected to the first and second rotor drivers independently of the spring, whereby the spring exerts bi-directional forces causing the first and second rotary seals to engage the first and second stationary seal seats, and wherein the set collar, the first and second rotor drivers and the first and second rotary seals define a positive drive mechanism for urging the first and second rotary seals against the first and second stationary seal seats upon rotation of the shaft. 9. The driven seal assembly of claim 8, wherein the first and second stationary seal seats are press fit and non-rotatably mounted in the bores of the seal and motor housings, respectively. 10. The driven seal assembly of claim 8, wherein the first and second rotary seals are lined with rubber surfaces that seal against an outer periphery of the shaft. 11. The driven seal assembly of claim 8, wherein the first and second rotary seals include multi-sided bosses. 12. The driven seal assembly of claim 11, wherein the first and second rotor drivers have a multi-sided wall structure matingly engageable with the multi-sided bosses on the first and the second rotary seals. 13. The driven seal assembly of claim 8, wherein each of the first and second rotor drivers has a circular crown integrally formed with an annular neck having a diameter less than a diameter of the crown. 14. The driven seal assembly of claim 13, wherein the spring surrounds the necks of the first and second rotor drivers and has opposite ends engaged against inner faces of the circular crowns of the first and second rotor drivers. 15. The driven seal assembly of claim 8, wherein each rotor driver is formed with a pair of axially extending apertures spaced substantially 180 degrees apart. 16. The driven seal assembly of claim 15, wherein the set collar is provided with a pair of axially extending pins that are received in the rotor driver apertures. 17. The driven seal assembly of claim 8, wherein the set collar is attached to the shaft by at least one set screw. 18. A driven seal assembly for a shaft rotated by a motor, the driven seal assembly comprising: a first rotary seal frictionally fit on the shaft; a first rotor driver mounted on the shaft in mating relationship with the first rotary seal, the first rotor driver being freely movable along the length of the shaft; a second rotary seal frictionally fit on the shaft; a second rotor driver mounted on the shaft in a mating relationship with the second rotary seal, the second rotor driver being freely movable along the length of the shaft; a set collar attached to the shaft for rotation therewith, the set collar being positioned between the first and second rotor driver and drivingly connected thereto; and a spring of substantially constant diameter surrounding the set collar in spaced relationship therefrom and placed in compression between the first and second rotor drivers, whereby the spring exerts a bi-directional force on the first rotor driver and the second rotor driver into engagement with the first and second rotary seal, and whereby the set collar is drivingly connected to the first and second rotor drivers independently of the spring. 19. The driven seal assembly of claim 18 wherein the set collar is fixedly attached to the shaft by at least one set screw and includes a pair of axially extending pins that are received in the first and second rotor drivers. 20. The driven seal assembly of claim 19 wherein the first and second rotary seals include multi-sided bosses and the first and second rotor drivers each include a multi-sided wall structure matingly engageable with the multi-sided bosses on the first and second rotary seals.