SHAFT TO SHAFT SCREW-LESS COUPLING
Certain aspects relate to shaft-to-shaft D-to-polygon connectors. The connector can have an interior channel with a “D-shaped” cross section to form a friction fit with an output shaft of a motor having a corresponding outer D-shape. The outer shape of the connector can be hexagonal, square, triple square, 12-point, or D-shaped. As such, when the connector is fit within a correspondingly shaped channel of another shaft or mechanical body, the torque from the motor is transmitted to the other shaft or mechanical body without the need for set screws.
1 . A coupling for transmitting torque between two mechanical bodies, the coupling comprising:
a body comprising:
a first end face having a polygonal shape,
a second end face on an opposing side of the body from the first face, the second face having the polygonal shape, and
a prismatic exterior formed by a plurality of exterior faces connecting corresponding sides of the first end face and the second end face;
a channel extending at least partway through the body, the channel having a D-shaped cross-section; and
wherein the body includes no apertures for receiving set screws or pins.
2 . The coupling of claim 1 , wherein the D-shaped cross-section of the channel is sized and shaped to form a friction fit with a D-shaped shaft of a first of the two mechanical bodies.
3 . The coupling of claim 2 , wherein the polygonal shape is selected such that the prismatic exterior forms a friction fit with a corresponding channel in a second of the two mechanical bodies.
4 . The coupling of claim 3 , wherein the friction fit between the D-shaped cross-section and the D-shaped shaft transmits torque from the first of the two mechanical bodies to the connector, and wherein the friction fit between the prismatic exterior and the corresponding channel transmits the torque from the connector to the second of the two mechanical bodies.
5 . The coupling of claim 4 , wherein the first of the two mechanical bodies comprises a D-shaped motor output shaft and wherein the second of the two mechanical bodies comprises a rotatable hinge.
6 . The coupling of claim 1 , wherein the polygonal shape of the first and second end faces comprises a hexagon and the prismatic exterior comprises a hexagonal prism.
7 . The coupling of claim 1 , wherein the polygonal shape of the first and second end faces comprises a triple square or 12-point polygon.
8 . The coupling of claim 1 , wherein the channel extends along a length of the connector from the first end face to the second end face of the body.
9 . The coupling of claim 1 , wherein the channel extends from the first end face along a portion of a length of the connector between the first end face to the second end face of the connector.
10 . The coupling of claim 1 , wherein the prismatic exterior extends from the second end face along a portion of a length of the connector between the first end face to the second end face of the connector.
11 . A coupling for transmitting torque between two mechanical bodies, the connector comprising:
a first end face;
a second face opposing the first end face;
a body extending between the first end face and the second end face; and
a channel extending at least partly through the body, the channel having a D-shaped cross-section extending at least partly along a length of the channel, the D-shaped cross-section sized such that the channel forms a friction fit with a D-shaped shaft of a first of the two mechanical bodies; and
a polygonal feature shaped to form a friction-fit with a corresponding polygonal feature of a second of the two mechanical bodies.
12 . The coupling of claim 11 , wherein the first end face and the second end face are hexagonal.
13 . The coupling of claim 12 , further comprising a hexagonal prism exterior of the body including six exterior faces connecting corresponding sides of the hexagonal first and second faces, and wherein the polygonal feature comprises the hexagonal prism exterior.
14 . The coupling of claim 13 , wherein the corresponding hexagonal feature of the second of the two mechanical bodies comprises a hexagonal channel, and wherein a size of the hexagonal first and second faces is selected such that the hexagonal prism exterior forms the friction-fit with the hexagonal channel.
15 . The coupling of claim 11 , wherein the D-shaped cross-section extends along a first portion of the length of the channel, and wherein the polygonal feature comprises a polygonal cross-section extending along a second portion of the length of the channel.
16 . The coupling of claim 15 , wherein the corresponding polygonal feature of the second of the two mechanical bodies comprises a hexagonal shaft, the polygonal cross-section comprising a hexagonal cross-section, and wherein a size of the hexagonal cross-section is selected such that the second portion of the length of the channel forms the friction-fit with the hexagonal shaft.
17 . The coupling of claim 11 , wherein the coupling transmits the torque from the first of the two mechanical bodies to the second of the two mechanical bodies via the friction fit between the D-shaped cross-section of the channel and the D-shaped shaft and via the friction fit between the polygonal feature and the corresponding polygonal feature.
18 . The coupling of claim 11 , wherein the coupling transmits the torque from the first of the two mechanical bodies to the second of the two mechanical bodies without set screws.
19 . The coupling of claim 11 , wherein the first of the two mechanical bodies comprises a D-shaped motor output shaft and wherein the second of the two mechanical bodies comprises a rotatable hinge.
20 . The coupling of claim 11 , wherein the body comprises 3-D printed plastic.