IP Library Granted Patent US 7,520,378
Granted Patent B2
US 7,520,378 · App. 10/849,512 · Granted Apr 21, 2009

Chain driven conveyor having automatic tensioning street sweeping method and system

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Quick Facts
Patent No.
US 7,520,378
App. No.
10/849,512
Granted
Apr 21, 2009
Kind
B2
Abstract

Disclosed herein is a street sweeper having a vertical chain driven conveyor apparatus. The vertical chain driven conveyor apparatus is provided with a jointed shaft to compensate for chain wear over the life of the chains. The vertical chain driven conveyor apparatus is provided with an automatically adjusting chain tension adjustment system. The vertical chain driven conveyor apparatus is provided with locking adjustment mechanism to prevent the chains from losing tension when the sweeper is turned off. An initialization program is operable to restore chain tension when the street sweeper is started and prevent sweeping operations until a desired chain tension has been indicated.

Claims (34)

1. A chain conveyor comprising:

a first driving shaft, the first shaft comprising a at least one multi-directional rotatable joint and ends of the shaft rotate about a horizontal axis while a central extent of the shaft between the joints rotates about an axis oriented at an angle with respect to the horizontal axis;

a second shaft;

at least a pair of chains operatively connecting the first and second shafts and

a pressure responsive cylinder having an extendible shaft for providing and maintaining tension in the chains

and further comprising a locking adjustment mechanism for maintaining tension in the chains when the conveyor Is not energized.

2. The conveyor according to claim 1 , further comprising independent automatically adjusting chain tensioning mechanisms for maintaining tension in each of the chains.

3. The conveyor according to claim 2 , wherein the chain adjusting mechanisms comprise a length adjustable cylinder having an extendible shaft for providing and maintaining tension in the chains.

4. The conveyor according to claim 2 , wherein the chain adjusting mechanisms comprise a pressure responsive cylinder being resiliently attached to at least one of said shafts, and having an extendible shaft for providing and maintaining tension in the chains.

5. A vertical conveyor apparatus comprising:

an upper driving shaft;

a lower shaft;

at least a pair of chains operatively connecting the shafts;

independent automatically adjusting chain tensioning mechanisms for maintaining tension in each of the chains including a pressure responsive cylinder having an extendible shaft for providing and maintaining tension in the chains; and

a plurality of flights, each flight associated with each of the chains

and wherein the upper driving shaft includes at least one rotatable multi-directional joint and portions of the shaft are oriented along different axes of rotation.

6. The conveyor apparatus according to claim 5 , wherein the chain adjusting mechanisms comprise a hydraulic cylinder having an extendible shaft for providing and maintaining tension in the chains.

7. The conveyor apparatus according to claim 5 , wherein the chain adjusting mechanisms comprise a pneumatic cylinder having an extendible shaft for providing and maintaining tension in the chains.

8. The conveyor apparatus of claim 5 , wherein the at least one rotatable multi-directional joint further comprises two rotatable multi-directional joints and ends of the shaft are oriented along a horizontal axis and a central extent of the shaft between the joints is oriented at an angle with respect to the horizontal axis.

9. The conveyor apparatus of claim 5 , further comprising a locking adjustment mechanism for maintaining tension in the chains.

10. A vertical conveyor apparatus comprising:

an upper driving wheel;

a lower driven wheel;

at least a pair of drive bands operatively connecting the wheels;

independent automatically adjusting band tensioning mechanisms for maintaining tension in each of the bands including a pressure responsive cylinder having an extendible shaft for providing and maintaining tension in the chains; and

a plurality of flights, each flight associated with each of the bands

wherein the upper driving wheel is operatively connected to a shaft including at least one rotatable multi-directional joint and portions of the shaft are orientable along different axes of rotation when band tension is adjusted.

11. The conveyor apparatus according to claim 10 , wherein the band adjusting mechanisms comprise a hydraulic cylinder having an extendible shaft for providing and maintaining tension in the bands.

12. The conveyor apparatus according to claim 10 , wherein the band adjusting mechanisms comprise a pneumatic cylinder having an extendible shaft for providing and maintaining tension in the bands.

13. The conveyor apparatus of claim 10 , wherein the at least one rotatable multi-directional joint further comprises two rotatable multi-directional joints and ends of the shaft are oriented along a horizontal axis and a central extent of the shaft between the joints is orientable at an angle with respect to the horizontal axis when band tension is adjusted.

14. The conveyor apparatus of claim 10 , further comprising a locking adjustment mechanism for maintaining tension in the bands.

15. The conveyor apparatus according to claim 10 , wherein the band adjusting mechanisms comprise a remotely adjustable mechanism for providing and maintaining tension in the bands.

16. The conveyor apparatus according to claim 10 , wherein the band adjusting mechanisms comprise a manual mechanical adjustment mechanism for providing and maintaining tension in the bands.

17. The conveyor apparatus according to claim 10 wherein the lower driven wheel is operatively connected to a shaft orientable along a horizontal axis of rotation when band tension is adjusted.

Assignments (4)
SECURITY INTEREST Recorded Apr 4, 2017
From: TENNANT COMPANY
To: JPMORGAN CHASE BANK, N.A., AS ADMINISTRATIVE AGENT
Reel/Frame 042188/0659 →
RELEASE OF SECURITY INTEREST Recorded Jan 28, 2015
From: JPMORGAN CHASE BANK, NATIONAL ASSOCIATION
To: TENNANT COMPANY
Reel/Frame 034837/0525 →
SECURITY AGREEMENT Recorded Mar 18, 2009
From: TENNANT COMPANY
To: JPMORGAN CHASE BANK, NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 022408/0546 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 17, 2004
From: HANSEN, KARL ROBERT; BLOCK, CRAIG DANIEL
To: TENNANT COMPANY
Reel/Frame 015359/0887 →