Resistance device for exercise machine

Abstract

A resistance device for an exercise machine may include a resistance element such as a fan or impeller that rotates within a cavity of a housing to produce resistance to a user's input. The resistance levels can be adjusted by a user by adjusting a movable baffle. The movable baffle may include an adjustment mechanism comprising a contoured guide surface that interacts with a protrusion on an adjacent component to move a portion of an outer region of the movable baffle outward to allow additional air into the cavity of the housing to adjust the resistance of the resistance device.

What is claimed: 
     
         1 . A resistance device for an exercise machine comprising:
 a housing comprising a first sidewall, a second sidewall opposite the first sidewall, and a third sidewall connecting the first sidewall and the second sidewall, an inner cavity defined by the first sidewall, the second sidewall, and the third sidewall, a first opening located in the third sidewall, and   the second sidewall comprising a recess that has a flange spaced below and away from an outer surface of the second sidewall and a second opening extending through the flange into the inner cavity, wherein the first opening defines an air exhaust and the second opening defines an air inlet;   a resistance element located within the housing, wherein the resistance element rotates within the housing to create resistance for a user;   the flange comprising a protrusion extending outward from an outward facing surface;   a fixed baffle connected to the housing, wherein the fixed baffle comprises a first plurality of openings, wherein the first plurality of openings allow an amount of air into the inner cavity;   a movable baffle that is rotationally connected to the second sidewall, the movable baffle comprising an inner member that includes a plurality of fins and a second plurality of openings;   the inner member includes an outer flange located outboard of the plurality of fins, wherein the inner member comprises a guide surface; and   wherein the protrusion contacts the guide surface to create a gap between the inner member and the flange to adjust an amount of air allowed to enter the inner cavity and adjust the resistance for the user.   
     
     
         2 . The resistance device of  claim 1 , wherein the protrusion comprises an upper surface and a transition surface between the outward facing surface and the upper surface. 
     
     
         3 . The resistance device of  claim 1 , wherein the protrusion comprises a plurality of protrusions positioned along the outward facing surface of the flange. 
     
     
         4 . The resistance device of  claim 3 , wherein the plurality of protrusions comprises three protrusions evenly spaced along the outward facing surface of the flange. 
     
     
         5 . The resistance device of  claim 1 , wherein the guide surface is formed on a guide member that is received in a pocket located on an inward facing surface of the outer flange. 
     
     
         6 . The resistance device of  claim 1 , wherein the guide surface has a first region with a first thickness and a second region with a second thickness, wherein the second thickness is greater than the first thickness. 
     
     
         7 . The resistance device of  claim 6 , wherein a ramped surface extends between the first region and the second region. 
     
     
         8 . An exercise machine comprising:
 a frame;   a resistance device connected to the frame and operatively connected to a user input mechanism, the resistance device comprising:   a housing defining an inner cavity with an air inlet on a sidewall, wherein the sidewall comprises a protrusion;   a resistance element rotatably mounted within the inner cavity, wherein resistance of the resistance device is dependent upon airflow through the air inlet; and   a component movably connected to the sidewall, wherein the component comprises a guide surface, wherein interaction between the protrusion and the guide surface creates a variable air gap between the sidewall and the component to adjust the resistance of the resistance device.   
     
     
         9 . The exercise machine of  claim 8 , wherein the user input mechanism may comprise a handle connected to the resistance element through a cable. 
     
     
         10 . The exercise machine of  claim 8 , wherein the exercise machine is a rowing machine, an exercise bike, a skiing exercise machine, a climbing exercise machine, a stair-climbing machine, an elliptical exercise machine, a squat exercise machine, or a bench press exercise machine. 
     
     
         11 . The exercise machine of  claim 8 , wherein the movable component comprises a movable baffle with fins that selectively cover openings on the sidewall to control airflow. 
     
     
         12 . The exercise machine of  claim 8 , wherein the variable air gap has a width within a range of 0.1 mm and 4 mm. 
     
     
         13 . The exercise machine of  claim 8 , wherein the guide surface has a second region that is positioned a first distance from an inward facing surface of the component to a second outward facing surface of the second region, and a first region that is positioned a second distance from the inward facing surface of the component and a first outward facing surface of the first region, wherein the first distance is less than the second distance. 
     
     
         14 . The exercise machine of  claim 13 , wherein a ramped surface extends between the first region and the second region. 
     
     
         15 . A resistance device for an exercise machine comprising:
 a housing comprising a first sidewall, a second sidewall opposite the first sidewall, and a third sidewall connecting the first sidewall and the second sidewall, an inner cavity defined by the first sidewall, the second sidewall, and the third sidewall, a first opening located in the third sidewall, wherein the first opening is an air exhaust,   the second sidewall comprising a second opening extending into the inner cavity that defines an air inlet;   a resistance element rotatably mounted within the inner cavity;   a plurality of protrusions extending from an outward facing surface of the second sidewall; and   a movable baffle for controlling airflow into the inner cavity connected to the housing, wherein the movable baffle comprising a plurality of guide surfaces; and   wherein a first guide surface of the plurality of guide surfaces is positioned to interact with a first protrusion of the plurality of protrusions to create an air gap between the movable baffle and the second sidewall.   
     
     
         16 . The resistance device of  claim 15 , wherein the first guide surface is located on a first guide member that is received in a pocket located on an inward facing surface of the movable baffle. 
     
     
         17 . The resistance device of  claim 16 , wherein the first guide member has a varying thickness along its length such that interaction between the first protrusion and the first guide surface such that the air gap between the movable baffle and the second sidewall is a variable air gap. 
     
     
         18 . The resistance device of  claim 17 , wherein the first guide member comprises a first region having a first thickness, a second region having a second thickness greater than the first thickness, and a ramped surface between the first region and the second region. 
     
     
         19 . The resistance device of  claim 15 , the first guide surface has a second region that is positioned a first distance from an inward facing surface of the movable baffle to a second outward facing surface of the second region, and a first region that is positioned a second distance from the inward facing surface of the movable baffle and a first outward facing surface of the first region, wherein the first distance is less than the second distance. 
     
     
         20 . The resistance device of  claim 19 , wherein a ramped surface extends between the first region and the second region.