Cam and lever assembly
A cam and lever system comprising a cam having a side perpendicular to an axis of rotation of the cam and a channel on the side of the cam, the channel having a bottom wherein the channel is at least partially defined by a first wall and a second wall that diverge as the distance from the bottom increases, a lever, having a pin extending into the channel and an axis of rotation that is generally parallel to the axis of rotation of the cam, and having a configuration sufficient to provide point contact with the walls of the channel.
1. An HVAC system for a vehicle comprising:
an air passage;
at least one air flow control member; and
a cam and lever system comprising:
a cam having a side perpendicular to an axis of rotation of the cam and a channel on the side of the cam, the channel having a bottom wherein the channel is at least partially defined by a first wall and a second wall that diverge as a distance from the bottom increases; and
a lever having a pin extending into the channel and an axis of rotation that is parallel to the axis of rotation of the cam, wherein the pin is configured to provide point contact at two points, a first point on the first wall of the channel and a second point on the second wall of the channel, without contacting the bottom of the channel, wherein the pin is conical with a cross section being formed by converging first and second lines, the first point being on the first line and the second point being on the second line,
wherein while the pin is in point contact with the first wall and the second wall of the channel, the pin cannot move tangentially without rotation of the cam, and
wherein the HVAC system is configured for use in a vehicle.
2. The HVAC system of claim 1 , wherein a ventilation door is mounted on the lever such that rotation of the cam causes the ventilation door to open or close.
3. The HVAC system of claim 1 , wherein an angle defined by a major axis of the pin and a surface of the pin is 0° to 30°.
4. The HVAC system of claim 1 , wherein an angle formed by the first wall and a line normal to the side of the cam is 7.5° to about 37.5°.
5. The HVAC system of claim 1 , wherein the channel is v-shaped.
6. The HVAC system of claim 1 , wherein an angle defined by a major axis of the pin and a surface of the pin is more acute than an angle formed by the first wall and a line normal to the side of the cam.
7. The HVAC system of claim 1 , wherein an angle defined by a major axis of the pin and a surface of the pin is less acute than an angle formed by the first wall and a line normal to the side of the cam.
8. The HVAC system of claim 1 , wherein the lever is positioned such that the pin is displaced by the cam, and a resulting mechanical stress on the lever is configured to bias the pin towards the bottom of the channel.
9. The HVAC system of claim 1 , wherein one of the cam and the lever is spring biased in order to bias the pin towards the bottom of the channel.
10. An HVAC system for a vehicle comprising:
an air passage;
at least one air flow control member; and
a cam and lever system comprising:
a cam having a side perpendicular to an axis of rotation of the cam and a channel on the side of the cam, the channel having a bottom wherein the channel is at least partially defined by a first wall and a second wall that diverge as a distance from the bottom increases; and
a lever having a pin extending into the channel and an axis of rotation that is parallel to the axis of rotation of the cam, wherein the pin is configured to provide point contact at two points, a first point on the first wall of the channel and a second point on the second wall of the channel, without contacting the bottom of the channel, and
wherein the pin is conical with a cross section being formed by converging first and second lines, the first point being on the first line and the second point being on the second line, and
wherein while the pin is in point contact with the first wall and the second wall of the channel, the pin cannot move tangentially without rotation of the cam.
11. The HVAC system of claim 10 , wherein an angle defined by a major axis of the pin and a surface of the pin is 0° to 30°.
12. The HVAC system of claim 10 , wherein an angle formed by the first wall and a line normal to the side of the cam is 7.5° to about 37.5°.
13. The HVAC system of claim 10 , wherein the channel is v-shaped.
14. The HVAC system of claim 10 , wherein an angle defined by a major axis of the pin and a surface of the pin is more acute than an angle formed by the first wall and a line normal to the side of the cam.
15. The HVAC system of claim 10 , wherein an angle defined by a major axis of the pin and a surface of the pin is less acute than an angle formed by the first wall and a line normal to the side of the cam.
16. The HVAC system of claim 10 , wherein the HVAC system is configured for use in a vehicle.
17. The HVAC system of claim 10 , wherein a ventilation door is mounted on the lever such that rotation of the cam causes the ventilation door to open or close.
18. The HVAC system of claim 10 , wherein the lever is positioned such that the pin is displaced by the cam, and a resulting mechanical stress on the lever is configured to bias the pin towards the bottom of the channel.
19. The HVAC system of claim 10 , wherein one of the cam and the lever is spring biased in order to bias the pin towards the bottom of the channel.