US4650259A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for tensioning ground engaging endless elastomeric belts
Assignee: Caterpillar Inc
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Filing: 1985-11-12
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Granted: 1987-03-17
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Expires: 2005-11-12
Abstract
Abstract Method and apparatus for selectively tensioning an endless, inextensible elastomeric belt entrained about a cooperating drive structure and idler structure having respective axes of rotation. A roller frame joined to a vehicular main frame supports the idler structure and constrains movement thereof to a longitudinal recoil path. The drive and idler structures are biasingly separated by a compression spring which exerts biasing force thereon in opposite longitudinal directions through a drive strut and an idler strut, respectively. The idler strut is connected to the idler structure longitudinally in front of the idler's axis. The length of one of the struts is adjustable to provide the desired tension in the spring and, thus, the entraining belt. Increases in tension are preferably provided by displacing one component member of the one strut relative to a second component member thereof-one of such members being reciprocatably receivable in the other and provided with a seal therebetween such that the two members cooperatively define a pressurizable chamber. Pressurized fluid, when transmitted into the pressurizable chamber, provides relative longitudinal displacement of the two members so as to decrease the spring and belt tension. A locking assembly threadably engaged with one of the members is rotated until it abuts the other member and permits the fluid pressure to be reduced while maintaining the length of such adjustable strut.
Inventors
- 👤 Phillip W. Alexander
- 👤 Michael S. Freberg
- 👤 Keith A. Howell
- 👤 James E. Johnston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:53
CPC Classifications
B; B62; B62D; B62D55/00; B62D55/08; B62D55/30
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
185 words
A belt laying work vehicle comprising: a main frame; a drive structure extending from a lateral side of said main frame and including a rotatable drive wheel having a drive axis of rotation; a roller frame disposed on a lateral side of and in rigid supporting relation to said main frame; an idler structure slidably mounted on said roller frame and including an idler shaft having an idler axis of rotation and a rotatable idler wheel mounted on said shaft; an endless, inextensible elastomeric belt entrained about said wheels; means for constraining and permitting relative movement between said idler structure and roller frame to a longitudinal recoil path during rotation of said idler structure; and means for adjustably biasing said belt into frictional driven engagement with said drive structure with a first force and for exerting a second compensating force on said drive structure which is equal in magnitude but opposite in direction to said first force, said biasing and force compensating means including apparatus for transmitting said first and compensating forces between said idler and drive structures independent of said main and roller frames.
Claim 2
Dependent Claim
185 words
A belt laying work vehicle comprising: a main frame; a drive structure extending from a lateral side of said main frame and including a rotatable drive wheel having a drive axis of rotation; a roller frame disposed on a lateral side of and in rigid supporting relation to said main frame; an idler structure slidably mounted on said roller frame and including an idler shaft having an idler axis of rotation and a rotatable idler wheel mounted on said shaft; an endless, inextensible elastomeric belt entrained about said wheels; means for constraining and permitting relative movement between said idler structure and roller frame to a longitudinal recoil path during rotation of said idler structure; and means for adjustably biasing said belt into frictional driven engagement with said drive structure with a first force and for exerting a second compensating force on said drive structure which is equal in magnitude but opposite in direction to said first force, said biasing and force compensating means including apparatus for transmitting said first and compensating forces between said idler and drive structures independent of said main and roller frames.
Claim 3
Dependent Claim
87 words
The belt laying work vehicle of claim 1 wherein said biasing and force compensating means comprises: a spring cooperatively associated with said roller frame; first means for connecting one end of said spring to said drive structure; second means for connecting the other end of said spring to said idler structure, wherein one of said connecting means includes a spring retainer engaged with an end of said spring; and means for adjusting the distance between said spring retainer and the structure connected by said one connecting means.
Claim 4
Dependent Claim
46 words
The belt laying work vehicle of claim 2, wherein said adjusting means comprises: a first member connected to one of said structures; a second member engaged with said spring retainer and disposed about said first member; and means for locking said first and second members together.
Claim 5
Dependent Claim
27 words
The belt laying work vehicle of claim 3, wherein said locking means comprises: means for threadably engaging said first member and for abuttably engaging said second member.
Claim 6
Dependent Claim
21 words
The belt laying work vehicle of claim 4, further comprising: means for fluidly separating said spring retainer and said first member.
Claim 7
Dependent Claim
70 words
The belt laying work vehicle of claim 5, wherein said fluid separating means comprises: said second member having an open and a closed end; said first member being reciprocatably receivable in said open end of said second member; means for fluidly sealing between said first and second members and, together with said first and second members, defining a variable volume chamber; and means for transmitting pressurized fluid into said chamber.
Claim 8
Dependent Claim
22 words
The belt laying work vehicle of claim 3, wherein said locking means comprises: means for threadably engaging said first and second members.
Claim 9
Dependent Claim
22 words
The belt laying work vehicle of claim 3, wherein said second member and said spring retainer are engaged at a spherical bearing.
Claim 10
Dependent Claim
41 words
The belt laying work vehicle of claim 2 wherein said first connecting means comprises: a bearing disposed about said drive structure; a bearing cage supportably disposed about said bearing; and a drive strut extending between said spring and said bearing cage.
Claim 11
Dependent Claim
52 words
The belt laying work vehicle of claim 2 wherein said constraining means comprises: one of said idler structure and said roller frame having a longitudinal slot; and a constraining element which resides in said slot includes a constraining axis and protrudes from the other of said idler structure and said roller frame.
Claim 12
Dependent Claim
40 words
The belt laying work vehicle of claim 10 wherein said second connecting means comprises: an idler strut biased by said spring; and a connecting pin which has a connection axis and which joins said idler strut to said idler structure.
Claim 13
Dependent Claim
22 words
The belt laying work vehicle of claim 11 wherein said constraining element constitutes one of said idler shaft and said connecting pin.
Claim 14
Dependent Claim
26 words
The belt laying work vehicle of claim 11 wherein said connection axis and said drive axis are disposed on opposite longitudinal sides of said idler axis.
Claim 15
Dependent Claim
19 words
The belt laying work vehicle of claim 13 wherein said idler and connection axes lie in a common plane.
Claim 16
Dependent Claim
19 words
The belt laying work vehicle of claim 10 wherein said constraining axis, idler axis, and drive axis are coplanar.
Claim 17
Dependent Claim
17 words
The belt laying work vehicle of claim 15 wherein said drive axis lies in said common plane.
Claim 18
Independent Claim
163 words
A method for adjusting the tension of an endless, inextensible ground engagement, vehicle propulsion belt entrained about a drive structure extending from a vehicle main frame, having a radially outwardly facing surface, and an axis of rotation and about an associated idler structure slidably supported on a roller frame which is rigidly connected to the main frame, said idler structure being connected to an idler strut and said drive structure being rotatably connected to a drive strut wherein said struts are engaged with opposite ends of a spring, said method comprising: lengthening one of said struts until said belt is frictionally coupled with and driven by said radially outwardly facing surface with a first force; transmitting a second, compensating force between said idler and drive structures independent of said main and roller frames; locking said strut in its lengthened configuration; and constraining relative movement of said idler structure and said roller frame to a longitudinal recoil path during rotation of said idler structure.
Claim 19
Independent Claim
163 words
A method for adjusting the tension of an endless, inextensible ground engagement, vehicle propulsion belt entrained about a drive structure extending from a vehicle main frame, having a radially outwardly facing surface, and an axis of rotation and about an associated idler structure slidably supported on a roller frame which is rigidly connected to the main frame, said idler structure being connected to an idler strut and said drive structure being rotatably connected to a drive strut wherein said struts are engaged with opposite ends of a spring, said method comprising: lengthening one of said struts until said belt is frictionally coupled with and driven by said radially outwardly facing surface with a first force; transmitting a second, compensating force between said idler and drive structures independent of said main and roller frames; locking said strut in its lengthened configuration; and constraining relative movement of said idler structure and said roller frame to a longitudinal recoil path during rotation of said idler structure.
Claim 20
Dependent Claim
190 words
A belt laying work vehicle comprising: a main frame; a drive structure including a drive wheel extending from a lateral side of said main frame and having a drive axis of rotation; a roller frame disposed on a lateral side of and in rigid supporting relation to said main frame; an idler structure longitudinally slidably mounted on said roller frame and including an idler shaft having an idler axis of rotation and a rotatable idler wheel mounted on said shaft, one of said idler structure and said roller frame having a longitudinal slot; an endless, inextensible elastomeric belt entrained about said wheels; a constraining element residing in said slot, protruding from the other of said idler structure and said roller frame having a constraining axis, and being displaceable in said slot during rotation of said idler wheel and longitudinal movement of said entraining belt; and means for adjustable biasing said wheels in opposite directions with a force to cause said belt to be in frictional driven engagement with said drive wheel, said biasing means including means for transmitting said force between said structures independent of said main and roller frames.
Claim 21
Dependent Claim
190 words
A belt laying work vehicle comprising: a main frame; a drive structure including a drive wheel extending from a lateral side of said main frame and having a drive axis of rotation; a roller frame disposed on a lateral side of and in rigid supporting relation to said main frame; an idler structure longitudinally slidably mounted on said roller frame and including an idler shaft having an idler axis of rotation and a rotatable idler wheel mounted on said shaft, one of said idler structure and said roller frame having a longitudinal slot; an endless, inextensible elastomeric belt entrained about said wheels; a constraining element residing in said slot, protruding from the other of said idler structure and said roller frame having a constraining axis, and being displaceable in said slot during rotation of said idler wheel and longitudinal movement of said entraining belt; and means for adjustable biasing said wheels in opposite directions with a force to cause said belt to be in frictional driven engagement with said drive wheel, said biasing means including means for transmitting said force between said structures independent of said main and roller frames.
Claim 22
Dependent Claim
63 words
The belt laying work vehicle of claim 18 wherein said adjustable biasing means includes: a spring cooperatively associated with said roller frame; an idler strut biased by said spring; and a connecting pin joining said idler strut to said idler structure and having a connection axis, said connection axis and said drive axis being disposed on opposite longitudinal sides of said idler axis.
Claim 23
Dependent Claim
176 words
A belt laying work vehicle comprising: a main frame; a drive structure including a rotatable drive wheel extending from a lateral side of said main frame and having a drive axis of rotation; a roller frame disposed on a lateral side of and in supporting relation to said main frame; an idler structure operationally slidably mounted on said roller frame and including an idler shaft having an idler axis of rotation and a rotatable idler wheel mounted on said shaft; an endless, inextensible elastomeric belt entrained about said wheels; means for constraining relative operational translational movement between said idler structure and said roller frame to a longitudinal recoil path; a spring having opposing ends cooperatively associated with said roller frame; an idler strut connecting one end of said spring to said idler structure about a connection axis, said connection axis and said drive axis being disposed on opposite longitudinal sides of said idler axis; and means for adjusting the distance between said spring ends and biasing said belt into frictional driven engagement with said drive wheel.
Claim 24
Dependent Claim
176 words
A belt laying work vehicle comprising: a main frame; a drive structure including a rotatable drive wheel extending from a lateral side of said main frame and having a drive axis of rotation; a roller frame disposed on a lateral side of and in supporting relation to said main frame; an idler structure operationally slidably mounted on said roller frame and including an idler shaft having an idler axis of rotation and a rotatable idler wheel mounted on said shaft; an endless, inextensible elastomeric belt entrained about said wheels; means for constraining relative operational translational movement between said idler structure and said roller frame to a longitudinal recoil path; a spring having opposing ends cooperatively associated with said roller frame; an idler strut connecting one end of said spring to said idler structure about a connection axis, said connection axis and said drive axis being disposed on opposite longitudinal sides of said idler axis; and means for adjusting the distance between said spring ends and biasing said belt into frictional driven engagement with said drive wheel.
Claim 25
Dependent Claim
19 words
The belt laying work vehicle of claim 20 wherein said idler and connection axes lie in a common plane.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-03-16 | 1990-09-15 | 1991-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-16 | 1994-09-15 | 1995-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-16 | 1998-09-15 | 1999-03-17 | $7700.00 | Window Closed / Lapsed |