Belt and belt drive assembly

Claim 2

A flexible power transmission belt used in conjunction with toothed and grooved pulleys of a belt drive assembly, said belt capable of driving from opposite portions thereof to transmit power between pulleys, said belt comprising: A. a first layer of flexible resilient material extending longitudinally of the belt to define one driving portion thereof and including a plurality of uniformly spaced teeth disposed to extend generally transversely thereof and adapted to mesh without change of pitch with teeth of the toothed pulleys; B. a second layer of flexible material spaced from and substantially parallel to said first layer to define the other driving portion of the belt facing in the opposite direction to that of the first mentioned driving portion, said second layer including a plurality of substantially V-shaped ribs disposed in parallel relation to each other across at least substantially the entire width of the belt and extending generally longitudinally thereof with at least the major portion of each rib engaging the grooves of the grooved pulleys having contours corresponding at least substantially thereto; and C. a tension section embedded therein including a tension member of high modulus essentially inextensible material disposed between said first and second layers substantially on the dedendum line of the teeth of said first layer, the first layer, second layer and tension section being bonded together to form an integral structure.

Claim 3

The belt as claimed in claim 1 wherein said second mentioned driving portion has an arc of contact with at least one of the grooved pulleys of less than 120*.

Claim 4

The belt as claimed in claim 2 wherein said second mentioned driving portion has an arc of contact with at least one of the grooved pulleys of from about 40* to about 60*.

Claim 5

The belt as claimed in claim 2 wherein each of the V-shaped ribs has a greater angle than the angle of the V-shaped groove of the pulley with which it is in engagement so that said ribs do not mate compleTely with the V-shaped pulley grooves but are adapted to wear to a more desired or correct profile during operation of the belt.

Claim 6

The belt as claimed in claim 4 wherein each V-shaped rib has an angle of from about 49* to about 55* and the angle of each V-shaped groove of the pulley is about 40* and about one-third of each rib extending from its base is in initial engagement therewith.

Claim 7

The belt as claimed in claim 2 wherein the V-shaped ribs are of a truncated transverse cross section.

Claim 8

The belt as claimed in claim 2 wherein said second layer is of a flexible polymeric material and at least the pulley contacting surface of the ribs has a relatively low coefficient of friction to allow for slippage of the belt during periods of high stress.

Claim 9

The belt as claimed in claim 7 wherein the ribs of said second layer are formed from a fiber-loaded elastomeric material.

Claim 10

The belt as claimed in claim 7 wherein the ribs of said second layer include a facing of textile fabric material.

Claim 11

In a belt drive assembly including the combination of toothed and grooved pulleys and a power transmission belt trained around said pulleys to transmit power therebetween with one side of the belt engaging the toothed pulleys and the opposite side engaging the grooved pulleys, the improvement wherein said belt comprises: A. a first layer of flexible resilient material extending longitudinally of the belt to define one driving portion thereof and including a plurality of uniformly spaced teeth disposed to extend generally transversely thereof and adapted to mesh without change of pitch with teeth of the toothed pulleys; B. a second layer of flexible material spaced from and substantially parallel to said first layer to define the other driving portion of the belt, said second layer including a plurality of substantially V-shaped ribs disposed in parallel relation to each other across at least substantially the entire width of the belt and extending generally longitudinally thereof and facing in the opposite direction to that of the teeth of the first layer with at least the major portion of each rib engaging the grooves of the grooved pulleys having contours corresponding at least substantially thereto; and C. a tension section embedded therein including a tension member of high modulus essentially inextensible material disposed between said first and second layers substantially on the dedendum line of the teeth thereof, the first layer, second layer and tension section being bonded together to form an integral structure.

Claim 12

In a belt drive assembly including the combination of toothed and grooved pulleys and a power transmission belt trained around said pulleys to transmit power therebetween with one side of the belt engaging the toothed pulleys and the opposite side engaging the grooved pulleys, the improvement wherein said belt comprises: A. a first layer of flexible resilient material extending longitudinally of the belt to define one driving portion thereof and including a plurality of uniformly spaced teeth disposed to extend generally transversely thereof and adapted to mesh without change of pitch with teeth of the toothed pulleys; B. a second layer of flexible material spaced from and substantially parallel to said first layer to define the other driving portion of the belt, said second layer including a plurality of substantially V-shaped ribs disposed in parallel relation to each other across at least substantially the entire width of the belt and extending generally longitudinally thereof and facing in the opposite direction to that of the teeth of the first layer with at least the major portion of each rib engaging the grooves of the grooved pulleys having contours corresponding at least substantially thereto; and C. a tension section embedded therein including a tension member of high modulus essentially inextensible material disposed between said first and second layers substantially on the dedendum line of the teeth thereof, the first layer, second layer and tension section being bonded together to form an integral structure.

Claim 13

A belt drive assembly comprising a plurality of rigid pulleys, at least one of which is a toothed pulley having a plurality of radial teeth disposed around the circumference thereof and at least one of which is a grooved pulley having a plurality of substantially V-shaped continuous annular grooves extending circumferentially in the face thereof, driving means for effecting the rotation of one of said pulleys, and an endless power transmission belt having one portion engaging the toothed pulley and the opposite portion engaging the grooved pulley, said belt comprising: A. a first layer of flexible resilient material extending longitudinally of the belt to define one driving portion thereof and including a plurality of uniformly spaced teeth disposed to extend generally transversely thereof and adapted to mesh without change of pitch with teeth of the toothed pulleys; B. a second layer of flexible material spaced from and substantially parallel to said first layer to define the other driving portion of the belt, said second layer including a plurality of substantially V-shaped ribs disposed in parallel relation to each other across at least substantially the entire width of the belt and extending generally longitudinally thereof with at least the major portion of each rib engaging the grooves of the grooved pulleys having contours corresponding at least substantially therEto; and C. a tension section embedded therein including a tension member of high modulus essentially inextensible material disposed between said first and second layers substantially on the dedendum line of the teeth thereof, the first layer, second layer and tension section being bonded together to form an integral structure.

Claim 14

A belt drive assembly comprising a plurality of rigid pulleys, at least one of which is a toothed pulley having a plurality of radial teeth disposed around the circumference thereof and at least one of which is a grooved pulley having a plurality of substantially V-shaped continuous annular grooves extending circumferentially in the face thereof, driving means for effecting the rotation of one of said pulleys, and an endless power transmission belt having one portion engaging the toothed pulley and the opposite portion engaging the grooved pulley, said belt comprising: A. a first layer of flexible resilient material extending longitudinally of the belt to define one driving portion thereof and including a plurality of uniformly spaced teeth disposed to extend generally transversely thereof and adapted to mesh without change of pitch with teeth of the toothed pulleys; B. a second layer of flexible material spaced from and substantially parallel to said first layer to define the other driving portion of the belt, said second layer including a plurality of substantially V-shaped ribs disposed in parallel relation to each other across at least substantially the entire width of the belt and extending generally longitudinally thereof with at least the major portion of each rib engaging the grooves of the grooved pulleys having contours corresponding at least substantially therEto; and C. a tension section embedded therein including a tension member of high modulus essentially inextensible material disposed between said first and second layers substantially on the dedendum line of the teeth thereof, the first layer, second layer and tension section being bonded together to form an integral structure.

Claim 15

The belt as claimed in claim 11 wherein said second-mentioned driving portion has an arc of contact with at least one of the grooved pulleys of less than 120* .

Claim 16

The belt as claimed in claim 12 wherein said second-mentioned driving portion has an arc of contact with at least one of the grooved pulleys of from about 40* to about 60*.

Claim 17

The belt as claimed in claim 12 wherein each of the V-shaped ribs has a greater angle than the angle of the V-shaped groove of the pulley with which it is in engagement so that said ribs do not mate completely with the V-shaped pulley grooves but are adapted to wear to the correct profile during operation of the belt.

Claim 18

The belt as claimed in claim 14 wherein the V-shaped rib has an angle of from about 49* to about 55* and the angle of each V-shaped groove of the pulley is about 40* and about one-third of each rib extending from its base is in initial engagement therewith.

Claim 19

A flexible power transmission belt of integral construction used in conjunction with pulleys of a belt drive assembly at least one of which is a grooved pulley, said belt capable of driving from opposite portions thereof to transmit power between pulleys from a power source, said belt comprising: A. a first layer of flexible material extending longitudinally of the belt to define one driving portion thereof; B. a second layer of flexible material spaced from and substantially parallel to said first layer to define the other driving portion of the belt facing in the opposite direction to that of the first-mentioned driving portion, said second layer including a plurality of substantially V-shaped ribs disposed generally longitudinal thereof and the major portion of each rib engages grooves of grooved pulleys having corresponding contours thereto with each of the ribs having a greater angle than the angle of the V-shaped groove of the pulley with which it is in engagement so that the ribs do not mate completely with the V-shaped pulley grooves but are adapted to wear to the correct profile during operation of the belt, and said second mentioned driving portion having an arc of contact with at least one of the grooved pulleys of less than 120* with the pulley contacting surface of the ribs having a relatively low coefficient of friction to allow for slippage of the belt during periods of high stress; and C. a tension section therein to provide longitudinal strength and stability.

Claim 20

A flexible power transmission belt of integral construction used in conjunction with pulleys of a belt drive assembly at least one of which is a grooved pulley, said belt capable of driving from opposite portions thereof to transmit power between pulleys from a power source, said belt comprising: A. a first layer of flexible material extending longitudinally of the belt to define one driving portion thereof; B. a second layer of flexible material spaced from and substantially parallel to said first layer to define the other driving portion of the belt facing in the opposite direction to that of the first-mentioned driving portion, said second layer including a plurality of substantially V-shaped ribs disposed generally longitudinal thereof and the major portion of each rib engages grooves of grooved pulleys having corresponding contours thereto with each of the ribs having a greater angle than the angle of the V-shaped groove of the pulley with which it is in engagement so that the ribs do not mate completely with the V-shaped pulley grooves but are adapted to wear to the correct profile during operation of the belt, and said second mentioned driving portion having an arc of contact with at least one of the grooved pulleys of less than 120* with the pulley contacting surface of the ribs having a relatively low coefficient of friction to allow for slippage of the belt during periods of high stress; and C. a tension section therein to provide longitudinal strength and stability.

Claim 21

The belt as claimed in claim 16 wherein said first layer is of a flexible polymeric material and includes a plurality of uniformly spaced teeth disposed generally transversely thereof and adapted to mesh without change of pitch with teeth of a toothed pulley of the belt drive assembly and said tension section includes a tensile member of high modulus essentially inextensible material disposed between said first and second layers substantially on the dedendum line of the teeth of said first layer.

Claim 22

The belt as claimed in claim 16 wherein said second-mentioned driving portion has an arc or contact with at least one of the grooved pulleys of from about 40* to about 60*.

Claim 23

The belt as claimed in claim 16 wherein the V-shaped rib has an angle of from about 49* to about 55* and the angle of the V-shaped groove of the pulley is about 40* and about one-third of each rib extending from its base is in initial engagement therewith.

Claim 24

The belt is claimed in claim 16 wherein the V-shaped ribs are of a truncated transverse cross section.

Claim 25

The belt as claimed in claim 16 wHerein the ribs of the second layer are formed from a fiber-loaded elastomeric material.

Claim 26

The belt as claimed in claim 16 wherein the ribs of said second layer include a facing of textile fabric material.