PLATE-LOADED CHEST PRESS EXERCISE MACHINE AND METHOD OF EXERCISE

Abstract: A user support (11) and a primary hinge (30) are mounted to a frame (10). A secondary hinge (32, 34) is mounted to the primary hinge (30). An arm (60) mounted to the secondary hinge has a handle (61) adapted to be grasped by the user. The two hinges permit the user to displace the handle in either or both the longitudinal and lateral directions. A means for resisting the displacement of the handle, preferably in both the lateral and longitudinal directions, is provided. The resistance means may include a post (62) attached to the arm for mounting weight plates. The arms may be connected such that both handles move the same longitudinal and/or lateral distance. To use the exercise machine (1), a user selects a weight for exercise, lies on the user support, grasps the handle and pushes upward from his shoulders, moving the handle longitudinally and laterally as he so chooses, overcoming the resistance.

Description: PLATE-LOADED CHEST PRESS EXERCISE MACHINE AND METHOD OF EXERCISE This is a continuation-in-part of an application filed March 1, 1995 assigned to the assignee of the present invention, entitled, "Rear Deltoid and Rowing Exercise Machine and Method of Exercising," Roy Simonson, inventor. This application is also related to an application filed concurrently herewith and assigned to the assignee of the present invention entitled "Plate-Loaded Shoulder Press Exercise Machine and Method of Exercising," Roy Simonson, inventor. Field of the Invention The invention relates generally to the field of exercise and physical rehabilitation equipment and, in particular, to an apparatus and method for exercising the upper torso. Background of the Invention It is often necessary or desirable for a person to exercise a particular muscle or group of muscles. For example, when a muscle is damaged, such as through injury or surgery, it is important to exercise the muscle to prevent atrophy and to strengthen the muscle for normal use. Further, people exercise healthy muscles to increase strength and to maintain an active and healthy lifestyle, as well as to improve their appearance. Various routines have been developed to exercise different muscle groups by forcing the muscles to contract and extend under a load, such as by moving a free weight against the force of gravity or by moving a handle whose movement is resisted by an exercise machine. The muscles of the chest, for example, may be exercised by an exercise known as the chest press. The chest press may be performed on either a flat, inclined or declined bench. The use of such different benches affects the region of the chest, e.g., middle, upper, lower, that is most optimally exercised. To perform the chest press with a barbell, an exerciser lies on his back, extends his arms substantially vertically and grasps a barbell that is typically supported by a frame above the exerciser's head. The exerciser lowers the barbell to his chest, then pushes the barbell upwardly, extending his arms. This exercise can be dangerous as the exerciser may not be able to control the downward motion of the barbell or may not be able to push the barbell off his chest. For this reason, the exerciser should have a partner to spot him. When using free weights, the resistance provided by gravity is constant while the strength of the muscles varies over the range of motion. Consequently, the muscles are not fully loaded at each point over the range of motion. During a chest press, the hands seek to follow a curved path inwardly as the arms are extended upwardly. This path cannot be followed when using a barbell because the hands are maintained at a fixed distance. This deficiency may be overcome by performing the exercise with dumbells. To overcome these difficulties, machines have been developed that simulate the exercise movements of a chest press. In U.S. patent no. 5,044,631, a decline chest press machine is disclosed in which two independently maneuverable levers are pivotally connected to a frame above a declined seat. Arms extend downwardly and rearwardly from the levers and angled handles are connected to the bottoms of the arms. Each handle is adapted to be grasped by a user supported on the seat and then pressed forwardly and upwardly in an arcuate path along a vertical plane that is described to converge inwardly with respect to the front of the declined seat. Resistance to handle movement is provided by weight plates mounted to the levers. The converging path is achieved by disposing hinges for the levers at an angle of 20° from the perpendicular to a central vertical midplane. As such, the user's hands must follow a preset rate of convergence and divergence during the exercise stroke, regardless of his anatomy. This apparatus does not permit the exerciser to select his own path of motion for the press exercise. Rather, the motion is dictated by the angle of the hinges. An upper extremity exercise apparatus is disclosed in U.S. patent no. 4,603,856. In this device, a bench is provided for an user to exercise in a prone or supine position. A shaft extends from a ball and socket joint mounted to the side of the bench, and a handle is slidably mounted to the shaft. Frictional resistance is provided both at the ball and socket joint and at the sliding connection between the handle and the shaft. The user exercises by moving the handle against one or both of these resistances. While providing multiple paths of motion through the range of the ball and socket joint, this machine provides for exercising only one arm at a time, cannot coordinate the motion of two arms, and has the disadvantages associated with frictional resistance such as changing resistance due to heat buildup, and wear. Further, this machine only provides concentric action (i.e., where the muscles contract against a load) . No eccentric action (i.e., where muscles extend under a load) is possible with this machine. Summary of the Invention It is therefore an object of this invention to provide an apparatus and method for performing a chest press exercise in which the user can vary the distance between his hands while performing the exercise. It is another object of the present invention to provide an apparatus and method for performing a chest press exercise in which a user can select the path of hand motion best suited for his particular anatomy. It is another object of the present invention to provide an apparatus and method for performing a chest press exercise in which a resistance is provided against the lateral movement of a user's hands. It is another object of the current invention to provide an apparatus and method for exercising the chest of a user which apparatus allows use of free weights to provide resistance. These and other objects of the invention will be clear from the following description of the invention. In accord with one aspect of the invention, an apparatus is provided for performing a chest press to exercise the muscles of a user. A primary hinge is mounted to a frame. A secondary hinge is mounted to the primary hinge. An arm is mounted to the secondary hinge. A handle is mounted to the arm distal to the secondary hinge. The handle is adapted to be grasped and displaced by the user. A resistance means such as a weight is attached to the arm at a point offset laterally outward from the handle. Due to the orientation of the two hinges, the handle may be displaced in both a longitudinal direction (upward) and a lateral direction (outward to the sides) , as selected by the user. Due to the offset of the resistance means, combined with the orientation of the two hinges, displacement is resisted in both the lateral and longitudinal directions. The resistance means may include a post attached to the arm for mounting free weight plates. A second handle, arm and secondary hinge may be provided for the other hand so that the user may exercise both halves of his body. The arms may be connected such that both handles move the same longitudinal and/or lateral distance. In accord with another aspect of the invention, a method is provided for performing a chest press exercise with an apparatus having an arm pivotally mounted to a frame. A user loads a weight plate on a post mounted to the arm and lies on a user support. The user grasps a handle mounted to the arm and pushes the handle upward longitudinally from about chest level, moving the handle longitudinally and laterally as he so chooses. The user overcomes resistance to the lateral movement of the handle and resistance to the longitudinal movement of the handle. The user may grasp a second handle with his other hand to exercise both halves of his body. The handles may be connected such that both handles move the same longitudinal and/or lateral distance. Brief Description of the Drawings FIG. 1 is a perspective view of an embodiment of a chest press exercise machine of the present invention in a static rest position; FIG. 2 is a partial perspective view of the hinge portion of the exercise machine of FIG. 1, with the arms partially cut away; FIGS. 3A-3C are schematic views of hinge mechanisms for use in the exercise machine of FIG. 1, in a plane IA-IA shown in FIG. 6; FIG. 4 is a side elevation view of the exercise machine of FIG. 1 with the arms in a rest position; FIG. 5 is a side elevation view of the exercise machine of FIG. 1 with the arms raised; FIG. 6 is plan view of the exercise machine of FIG. 1; FIG. 7 is front elevation view of the exercise machine of FIG. l, with the arms in the static rest position; FIG. 8 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having hinge plates; FIG. 9 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having a slider link; FIG. 10 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having a cam link; FIG. 11 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having variable length links with resistance; FIG. 12 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having a spring pulley linkage; FIG. 13A is a front elevational view of a weight stack of an embodiment of the invention; FIG. 13B is a side elevational view of the weight stack of FIG. 13A; FIG. 14 is a partial schematic view of the hinge mechanism, arms and handles of an embodiment of the invention having incrementally adjustable handle resistance; FIG. 14A is a partial schematic view of the hinge mechanism, arms and handles of an embodiment of the invention having discrete degrees of resistance; FIG. 15 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having incrementally adjustable handle resistance; FIG. 15A is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having discrete levels of resistance. FIG. 16 is a schematic view of the hinge mechanism of an embodiment of the invention having torsion springs to resist lateral movement; FIG. 17 is a schematic view of the hinge mechanism, arms and handles of an embodiment of the invention having a pivoting handgrip; FIG. 18 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having large gears; FIG. 19 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having a rack and pinion link; FIG. 20 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having a belt and pulley link; FIG. 21 is a partial schematic view of the hinge mechanism, arms and handles of an embodiment of the invention having outward sliding hand grips; FIG. 21A is a partial schematic end view of the arms and handles of FIG. 21; FIG. 2IB is a partial schematic end view of the arms and handles of an embodiment of the invention having angled handle rods; FIG. 21C is a partial schematic end view of the arms and handles of an embodiment of the invention having angled handle rods; FIG. 21D is a partial schematic end view of the arms and handles of an embodiment of the invention having a handle rod resistance mechanism; FIG. 21E is a partial schematic end view of the arms and handles of an embodiment of the invention having a handle rod resistance mechanism; FIG. 2IF is a partial schematic end view of the arms and handles of an embodiment of the invention having a handle rod resistance mechanism; FIG. 22 is a partial schematic view of the hinge mechanism, arms and handles of an embodiment of the invention having inward sliding hand grips; FIG. 22A is a partial schematic end view of the arms and handles of FIG. 22; FIG. 22B is a partial schematic end view of the arms and handles of an embodiment of the invention having angled handle rods; FIG. 22C is a partial schematic end view of the arms and handles of an embodiment of the invention having angled handle rods; FIG. 22D is a partial schematic end view of the arms and handles of an embodiment of the invention having a handle rod resistance mechanism; FIG. 22E is a partial schematic end view of the arms and handles of an embodiment of the invention having a handle rod resistance mechanism; FIG. 22F is a partial schematic end view of the arms and handles of an embodiment of the invention having a handle rod resistance mechanism; FIG. 23 is a partial schematic view of the hinge mechanism, arms and handles of an embodiment of the invention having sliding handles with cable resistance; FIG. 23A is a partial detail perspective view of an arm and handle of the machine of FIG. 23; FIG. 24 is a partial schematic view of the hinge mechanism and arms of an embodiment of the invention having a pivoting bar linkage; FIG. 25 is a schematic view of the hinge mechanism of an embodiment of the invention having an adjustable arm angle; FIG. 26 is a cross-sectional view of a self-aligning pulley for use with an exercise machine, including the machine of FIG. 13; FIG. 27 is a cross sectional view of the pulley of FIG. 26, taken through section XXVII-XXVII; FIG. 28 is another cross-sectional view of the pulley in the same section as FIG. 26, showing a misaligned frame; FIG. 29 is a perspective view of an incremental weight stack for use with an exercise machine, including the machine of FIG. 13. Detailed Description FIG. 1 is a perspective view of an embodiment of the chest press machine 1 of this invention in the static rest position. Unless otherwise noted, the structural components of the machine are formed of a mild steel. The exercise machine has a frame 10 comprising a front leg 20, a lower brace 22, an upper brace 24, arm support housings 23, a rear brace 26 and a hinge brace 28 (see FIG. 4) . Optionally, the frame may further comprise a rear brace support 29. In the preferred embodiment, the frame is constructed of 2-inch square, 11 gauge steel tubing. A bench 12 is mounted on, and supported by, the front leg 20 and the upper brace 24 of the frame. The bench 12 should have a width W suitable to comfortably support a user in a stable position during the exercise. A foot brace 5 is attached to the front leg 20. The foot brace 5 may be used to help stabilize a user during exercise. Arms 60 are mounted to the frame 10 by a hinge mechanism 50, including a primary hinge 30 and secondary hinges 32 and 34. The primary hinge 30 is mounted to the frame 10. In a preferred embodiment, the hinge brace 28 of the frame curves upward at the rear of the frame for mounting the primary hinge 30 (see FIG. 4) . The primary hinge is disposed perpendicularly to a horizontal plane X-X (see FIG. 6) extending through the center of the machine 1. In a currently preferred embodiment, the primary hinge 30 is disposed behind the back of the bench 12 and fixed atop the hinge brace 28. In other embodiments, the primary hinge 30 and/or the front end 11 and/or the back end 13 of the bench 12 could be vertically adjustable to affect a decline or incline chest press, as well as a flat chest press. Handles 61 are mounted at the end of the arms 60 distal to the hinge mechanism 50. Other handle positions than that shown in the Figures, or a variable position handle such as a pivoting handle, could alternatively be used. Posts 62 extend outwardly from the arms 60 for mounting weight plates 23 (see FIG. 6) . As discussed more fully below, the user exercises by pushing handles 61 upward from a rest position, overcoming the resistance of gravity on the weight plates. Of course, other mechanisms for providing resistance, such as a friction, springs, elastic bands, pneumatic or electromagnetic resistance, or an air resistance fan could be employed (either alone or in combination) and still practice the invention. Additionally, a weight stack could be operably engaged to the arms 60 to resist the movement of handles 61. Each end of the upper brace 24 and the lower brace 22 is attached to one of the arm support housings 23. When the exercise machine 1 is not in use, the arms 60 rest on static supports 21 which are positioned, one on each side of the bench, about mid-way between an edge of the bench and the arm support housing 23. In a preferred arrangement, the static supports 21 support the arms 60 at a point along the arms about mid-way between the primary hinge 20 and the posts 62. A rubber or elastomer bumper 59 is mounted to the arm at this point to protect the arm. The static supports 21 are sized so that when the arms 60 are resting on the static supports, the arms maintain an approximately horizontal orientation. Within each arm support housing 23 is a telescoping rod 16 having holes 17 which terminates in an arm support 18 (see FIG. 7) . A pin 19 is received by the holes 17 in the telescoping rod 16 to set the arm support 18 at a desired height. Before using the exercise machine 1, a user sets each arm support 18 to a desired height as discussed above, and then places each arm 60 on an arm support in an exercise rest position. Weights may then be placed on the posts 62. In this manner, users having different chest sizes, arm length and flexibility may set the arms 60 at a comfortable level relative to their chest. The arms 60 may remain on the static supports 21 (the static rest position) while the arm supports 18 are adjusted. In this manner, the user does not have to hold the arm 60 with one hand and adjust the arm support 18 with the other hand. The front leg 20 and the arm support housings 23 are supported at their lower ends by plate members 3 and 4, respectively. Preferably, bolt holes are provided in the plate members to allow the exercise machine 1 to be secured during transit or for normal use. FIG. 2 is a perspective view of the hinge mechanism 50 with the arms 60 partially cut away. The primary hinge 30, as currently preferred, includes a primary bearing tube 31 mounted on sealed bearings (not shown) , such as model #87503 metric bearings manufactured by Fafnir, or an equivalent. The primary bearing tube 31 is rotatable about a primary axis 46 which axis is disposed perpendicular to the horizontal plane X-X (FIG. 6) through the center of the machine. Brackets 47 are rigidly mounted to the primary bearing tube 31, such as by welding. The secondary hinges 32 and 34 are rotatably mounted to the brackets. The secondary hinges include the secondary bearing tubes 33 and 35 mounted to sealed bearings (not shown) , such as model #87503 metric bearings manufactured by Fafnir, or an equivalent. The secondary bearing tubes are rotatable about secondary axes 48 and 49. The secondary hinge axes 48 and 49 are skew to the primary hinge axis 46; in other words, the secondary hinge axes are not parallel to the primary hinge axis. The arms 60 are rigidly attached to the secondary bearing tubes 33 and 35 approximately perpendicular to the secondary hinge axes. As discussed more fully below, the lateral offset of the weight post 62 to the handles 61, combined with the angular relationship of the primary hinge 30 to the secondary hinges 32 and 34, affects the resistance to handle movement. As currently preferred, the angular relationship of the hinges is fixed. Referring to FIGS. 3A, 3B and 3C, which are schematic views of the primary hinge and secondary hinges in plane IA-IA (see FIG. 4) , the secondary hinges are disposed at an angle A with respect to the primary hinge. The preferred angle A is 115°, as shown in FIG. 3C and explained below. As the exerciser lifts the handles 61 during an exercise stroke, most of the weight of the plates 23 is supported by the user as longitudinal (downward) resistance. Because the weight plates 23 are located on the arms 60 between the handles 61 and the hinge mechanism 50, the remaining portion of the weight is supported by the hinge mechanism 50. Further, the hinge mechanism must absorb considerable torsion transmitted through the arms 60, because the weight plates are offset laterally outward from the handles 61 by a distance R (see FIG. 6) . The hinge mechanism 50 operates to utilize these forces to create a lateral (outward) component of resistance. The combination of lateral and longitudinal resistance increases the effectiveness of the chest press exercise and provides feedback to the user that encourages symmetrical exercise paths of the right and left hands. FIGS. 3A, 3B and 3C are schematic views of hinge mechanism 50 showing the secondary hinge angle A. With a secondary hinge angle A other than 90°, as shown in FIGS. 3A and 3C, asymmetry between the position of the user's right and left hands during an exercise stroke will cause the user to feel asymmetric feedback from the machine. The typical user will naturally seek to distribute the load equivalently between the left and right sides. Consequently, the secondary hinge angle of more or less than 90° encourages the user to move his hands symmetrically. The more the secondary hinge angle A diverges from 90°, the more the user is encouraged to perform the exercise symmetrically. By providing lateral resistance, and by encouraging a symmetric stroke, the hinge mechanism 50 can make the exercise machine feel "stable" as perceived by a user. It has been found that in using a machine with a hinge angle A of 90°, the user perceives that the exercise stroke is unstable because lateral hand movement is unresisted. This sensation is more pronounced in exercises requiring pushing, such as the chest press exercise of the present exercise machine, than in pulling exercises. A machine with a hinge angle A other than 90° feels more stable to a user because it resists lateral movement and encourages a symmetrical stroke. The perception of stability increases as angle A diverges from 90°. The preferred secondary hinge angle of 115° (as shown in FIG. 3C) has been found by experimentation to produce the most comfortable chest press exercise stroke. In particular, the relationship of lateral resistance to longitudinal resistance at this angle seems to provide an effective exercise for the muscles of the chest. Further, sufficient lateral resistance is provided so that a user perceives the chest press exercise as stable. Other secondary hinge angles could be selected for a chest press apparatus based on the comfort, stability, muscular development or exercise goals of a particular group of users to emphasize the longitudinal or lateral resistance to the exercise. FIG. 4 is a side elevation view of the chest press exercise apparatus in the rest position without weight plates mounted on the posts 62. In the rest position, the post 62 is at about the level of the primary hinge 30. As the handle 61 is raised, the movement of post 62, and any weight plates mounted on it, approximates an arc about the primary hinge 30. Near the rest position, the weight of the plate 23 acts in a direction opposite the path of the weight plates, providing a maximum resistance in the exercise stroke. As the arms move upward through an angle θ (FIG. 5) , the component of the weight acting to resist arm motion decreases. FIG. 5 is a side elevation view of the chest press exercise apparatus without weight plates mounted on the posts 62. The arms are in an elevated position, having lifted the post 62 and any weight thereon to an angle θ above the horizontal. The secondary hinges have rotated upward about the primary hinge. FIG. 6 is a plan view of the chest press exercise machine of the invention in the rest position with a weight plate 23 mounted to one of the posts 62. An arm strap 53 connects the arms 60 to limit outward travel of the arms during the exercise stroke and in the rest position. The arm strap is preferably KEVLAR® fabric, although other high-strength tethers could be used. Preferably, the strap is held on the arms by a pressure plate 54 that clamps the strap to the arms. The strap is positioned on the arms 60 so that it remains behind the user's head. Alternatively, other mechanisms for limiting arm travel, such as mechanical stops attached to the secondary bearing tubes, could be used and still practice the invention. In an alternate embodiment, a means for limiting the inward travel of the arms 60 during the exercise stroke is used. Such a means includes, without limitation, mechanical stops attached to the secondary bearing tubes. FIG. 7 is a front elevation view of the apparatus of FIG. 1 in the rest position. The weight posts 62 are inclined upward approximately 25° in order to safely retain the weight plates 23. To operate the apparatus of the present invention, the arm supports 18 are adjusted to a desired height while the arms are in the static rest position, and the arms 60 are moved from the static supports 21 to the arm supports 18. Weight plates are mounted on the posts 62 corresponding to the resistance desired. Preferably, the same weight is placed on each one of the posts. The user lies face up on the bench, orienting himself so that his shoulders are approximately in line with the handles 61. The user then grasps the handles at a selected position. A narrower grip, i.e., hands relatively closer to the centerline of the bench, will result in an increasing contribution by the tricep muscles in performing the exercise. A wider grip, i.e., hands closest to the arms 60, will result in an increasing contribution by the pectoral muscles in performing the exercise. After grasping the handles, the user pushes upwardly. The movement of the handles causes rotation of the arms 60, the secondary bearings 32 and 34 and the brackets 47 about the primary bearing 30. As the arm rotates, it lifts the posts 62 and weights 23. The user then returns the handles to the initial position, thereby lowering the weight plates. When the user pushes the handles upward (concentric action) , he overcomes the resistance provided by the weight. When the user returns the handles (eccentric action) , he succumbs to the resistance provided by the weight. A user may choose to emulate a traditional chest press exercise by grasping the handles 61 in the rest position (a wide hand width) and pressing directly upward while maintaining his hands at a constant width. In this exercise, the arm strap 53 between the arms 60 remains taut, and there is no lateral movement of the handles. As a result, the secondary bearing tubes 33 and 35 are not caused to rotate with respect to the brackets 47. Rather, only the primary bearing tube 31 rotates and the handles follow a path similar to that of traditional machines. Alternatively, the user may choose a chest press exercise with an inward lateral component of motion. In this exercise, the user begins the exercise stroke by grasping the handles 61 at the rest position, pressing upward at the beginning of the stroke and bringing the handles together in an arcuate path at the end of the stroke. The user encounters resistance in both the longitudinal and lateral components of the concentric portion (i.e., where the muscles contract against the load) of the stroke. In a traditional machine, this would not be possible. In the apparatus of the present invention, however, the hinge mechanism 50 allows such movement. The outward offset R of the weight plates to the handles (FIG. 6) causes the hinge mechanism 50 to resist the lateral component of movement. It can be seen in FIG. 6 that the axis A-A which passes through the user's grip on the handle 61, can be moved by the user by moving his grip on the handle. This, in turn, increases or decreases the offset R, which in turn affects the resistance to the lateral component of movement. The user can therefore select, to some extent, the ratio of lateral to longitudinal resistance by his grip placement on the handle 61. Advantageously, the user cannot "lock out" his elbows at the end of the exercise stroke to transfer the load from the muscular system to the skeletal system, as is possible on traditional machines and free weights. In the exercise machine of the invention, the lateral component of the resistance continues to oppose the chest muscles even when the user's elbows are straightened. The hinge mechanism 50 permits movement of the handles 61 upward (i.e., longitudinally) and inward (i.e., laterally) in a relationship selected by the user. Consequently, the user can grasp the handles and push upward and inward in the natural arcuate path. Alternatively, the user can select another path to give the muscles a different workout. For example, the user may wish to push directly upward and then move directly downward, emulating the purely longitudinal motion of a traditional chest press. The user may instead choose to press his hands directly upward, and then, at the end of the stroke, move his hands in latitudinally while his arms are fully extended. The user can even chose a "figure eight" path, moving his hands in, out, in and out again during the exercise stroke. Any combination of such movements can be accomplished with the machine of the present invention. The user has flexibility in how he exercises the muscles of his chest. The resistance overcome by the particular muscle group is determined, in part, by the selected path of the hands and the secondary hinge angle A. The offset R and the secondary hinge angle A are selected to present a combination of lateral resistance and longitudinal resistance that feels comfortable or natural to a typical user moving his hands in an arcuate path. Consequently, the user defines, in part, the resistance profile by his path selection. The double hinge mechanism 50, in combination with the weight placement on the arms thus provides a fundamental advance over existing exercise machines by establishing a ratio of lateral to longitudinal resistance while encouraging left-to-right hand symmetry in the exercise stroke and allowing the user to select the path of the stroke and the muscle group emphasized. Since the secondary bearing tubes 33, 35 are both mounted to the primary bearing tube 31 at symmetrical orientations, the hinge mechanism 50 encourages symmetrical movement of the handles 61. Such symmetrical movement, however, is not required. The user can move his hands through different paths during the same exercise stroke. While this configuration is currently the preferred embodiment of the invention, it may be advantageous in some situations to further couple the motion of the arms, as is done in several of the following additional embodiments. FIG. 8 is a schematic plan view of the hinge mechanism 80 and arms 81 of another embodiment of the invention. The secondary hinges 82 are shown disposed perpendicular to the primary hinge 83, although they may be oriented at other angles. Flanges 84 are pivotally mounted to each arm, such as by piano hinges 85. The flanges 84 are rotatably mounted to each other, such as by a knuckle joint 86. The arms and flanges constrain the knuckle joint to move within the plane of symmetry S-S between the arms. Since the linkage formed by the primary bearing tube 87, the arms and the flanges is symmetrical, the arms must translate the same amount laterally. Consequently, the arms (and thus the handles) are forced to move symmetrically. Alternatively, the hinges, flanges and knuckle joint may be constructed of a resilient material such as plastic, elastomer or rubber. For example, the knuckle joint may be a deformable rubber connector, or the hinges, flanges and knuckle may be a one-piece polymer part with reduced cross sections in the areas requiring flexure. Such embodiments encourage symmetric exercise strokes while permitting some left-to-right asymmetry. FIG. 9 is a schematic plan view of the hinge mechanism 90 and arms 91 of another embodiment of the invention. Again, the arms are operably engaged such that they must move symmetrically in the lateral direction. The secondary 92 hinges are again shown disposed perpendicular to the primary hinge 93, although other angles of attachment are possible. A slider rod 94 is fixedly mounted to the primary hinge 93. A slider ring 95 is mounted to the slider rod 94 and adapted to be displaceable along its length. Links 96 are pivotally mounted to the slider ring and to each arm 91. Consequently, as the arms are displaced laterally, the slider ring is caused to move along the slider rod. Due to their mutual connection to the slider ring, both arms are caused to move symmetrically about the secondary hinges. FIG. 10 is a schematic plan view of the hinge mechanism 100 and arms 101 of another embodiment of the present invention. The secondary hinges 102 are shown mounted perpendicularly to the primary hinge 103, although other attachment angles are possible. A barrel cam 104 having mirrored, grooved profiles 105 is mounted to the primary bearing tube 108 equidistant from both secondary hinges 102. The barrel cam is mounted for rotational movement. A rigid link 106 with a cam follower 107 is pivotally mounted to each arm. As an arm is moved outward, the barrel cam is forced to rotate about its axis, causing the other rigid link to force the other arm to move the same lateral distance. FIG. 11 is a schematic plan view of the hinge mechanism 110 and arms 111 of another embodiment of the invention. The secondary hinges 112 are shown mounted perpendicularly to the primary hinge 113, although other attachment angles are possible. An anchor 114 is rigidly mounted to the primary hinge between the secondary hinges 112. A variable length link 115 engages each arm 111 to the anchor. A resistance mechanism 116, such as a pneumatic, hydraulic, spring, elastic band, electrical or magnetic resistance, is operably engaged to the link 115 to resist any change is length. Consequently, the mechanism provides resistance to lateral movement of the arms 111 during the exercise stroke. Also, the resistance mechanism discourages quick, lateral movement of the arms. The mechanism 110 thus provides resistance to lateral movement both inward and outward, while encouraging a smooth stroke. FIG. 12 is a schematic plan view of the hinge mechanism 120 and arms 121 of another embodiment of the invention. The secondary hinges 122 are shown mounted perpendicular to the primary hinge 123. However, other orientations are possible. Branches 124 are fixedly mounted to the primary bearing tube 129. A pulley 125 is mounted on each branch and disposed in the same plane as its respective arm. Cables or belts 126 are attached to the arms 121, extend over the pulleys 125 and attach to a plate 127. The plate is attached to the primary bearing tube 129 by a resistance 128, which can be a spring, or can be another resistance device such as hydraulic, pneumatic, frictional or electromagnetic. As the arms are displaced laterally, the plate 127 is pulled from the primary hinge. This lateral movement is resisted by the resistance 128. The cables 126 could be attached to the arms 121 to resist outward movement, as shown, or to resist inward movement. The plate 127 could be journalled in a track, or mounted on rails (not shown) , such that the orientation of the plate with respect to the primary hinge is fixed. Consequently, as one arm is displaced laterally, the other arm is free to rotate the same lateral distance. FIG. 13A is a schematic front elevation view of a weight resistance assembly 130 of an embodiment of the invention including a weight stack 131 as is known in the art. FIG. 13B is a side view of the assembly with the weight stack. In this embodiment, the spring 128 shown in FIG. 12 is replaced by a cable or belt 132. A pulley 133 is mounted on or near the primary hinge to direct the cable or belt for attachment to the weight stack 131. Consequently, to move the arms laterally, the user must pull on the cable or belt, thereby lifting the weight stack. The user thus has the freedom to select the resistance to the lateral movement of the hands. In another version of this embodiment, separate weight stacks are provided to resist the lateral movement of each arm. FIG. 14 is a schematic front view of a hinge mechanism 140 of another embodiment of the present invention. The secondary hinges 142 are shown disposed perpendicular to the primary hinge 143, although other orientations could be used. Rigid members 144 are mounted to the primary hinge 143 and disposed in the plane of rotation of the arms 141 about the secondary hinges 142. A resistance means 145, such as a spring, is operably engaged to each arm 141 and its respective rigid member 144. The resistance means resists the lateral movement of the arm outward. The resistance means may be disposed at different points along the arm and the rigid member to vary the lateral resistance. The shape of rigid member 144 or the angle of attachment of the rigid member to the primary hinge 143 may be chosen to further define the resistance profile as means 145 is moved along the arm. The angle of attachment may further be adjustable. The resistance means 145 may be attached to both the arm 141 and the member 144 to operate in both tension and compression, providing bidirectional resistance to lateral arm movement. FIG. 14A shows another embodiment or the hinge mechanism 140 of FIG. 14, with the resistance means 145 comprising a set of springs 146, 147, 148 mounted to a ring 149. The ring is rotatably mounted to the rigid member 144 such that each spring can be indexed into contact with the arm 141. Each spring 146-148 has a different spring constant and thus provides a different resistance to the lateral movement of the arms. FIG. 15 shows the hinge mechanism 150 and arms 151 of another embodiment of the present invention. The secondary hinges 152 are shown disposed perpendicular to the primary hinge 153. A central member 154 is mounted to the primary hinge 153 between the secondary hinges and disposed in the same plane as the arms 151. The angles or shape of the central member may be adjustable. A resistance means 155, such as a spring, is operably engaged to each arm 151 and the central member 154. The resistance means 155 resists the lateral movement of the arm toward the central member. This results in resistance to the lateral displacement of the handles (not shown) toward the center. The resistance means 155 may be moved by the user to different points along the arm and the central member to vary the resistance. Alternatively, a single spring could be mounted to each arm, thereby connecting the arms. FIG. 15A shows the hinge mechanism 150 of FIG. 15 with an alternative resistance means. The resistance means in this embodiment comprises spring pairs 157 and 158 mounted to a ring 159. The ring is rotatable about the rigid member 156 such that a different spring pair may be indexed into contact with the arms. Each spring pair 157 and 158 has a different spring constant and thus provides a different resistance to the lateral movement of the arms 151. The ring 159 may be made displaceable along the length of the rigid member 156 to additionally vary the resistance to lateral movement of the arms 151. FIG. 16 is a front schematic view of the hinge mechanism 160 of another embodiment of the invention. The secondary hinges 162 are shown disposed perpendicular to the primary hinge 163, although other secondary hinge angles are possible. A torsion spring 164 is mounted to the primary hinge 163 near each secondary hinge 162 and operably engaged to the respective arm 161. The torsion spring resists the rotation of the arm about the secondary hinge. The torsion spring may be disposed to resist either inward movement of the arm or outward movement of the arm. FIG. 17 is a schematic front view of the hinge mechanism 170, arms 171 and handles 172 of another embodiment of the invention. The arms 171 are directly mounted to the primary hinge 173. The handles 172 are pivotally mounted to the arms and adapted to rotate in a plane perpendicular to the arms about a handle peg 175. A spring 174, such as a torsion spring or other resistance mechanism, may resist the rotation of the handle 172 about the handle peg 175. FIG. 18 is a schematic plan view of the hinge mechanism 180 and arms 181 of another embodiment of the invention. The secondary hinges 182 are shown mounted perpendicular to the primary hinge 183, although other attachment angles are possible and still practice the invention. A large spur gear 184 is fixedly mounted to each arm 181 and adapted to rotate about its respective secondary hinge 182. The teeth of the large spur gears 184 engage each other such that the arms are caused to rotate about their respective secondary hinges together. Consequently, the handles and the user's hands are displaced symmetrically with respect to a central vertical plane. In the case where the secondary hinges are not perpendicular to the primary hinge, the large spur gears could be replaced by bevel gears. FIG. 19 is a schematic plan view of the hinge mechanism 190 and arms 191 of another embodiment of the invention. The secondary hinges 192 are shown mounted perpendicularly to the primary hinge 193, although other attachment angles are possible. Gears or pinions 194 are attached to each arm 191 and adapted to rotate about the secondary hinges 192 with the respective arm. A rack 195 is operably engaged to the pinions 194, forming a "rack and pinion" system which causes the arms to rotate about their respective secondary hinges 192 symmetrically. Consequently, the arms 191 are forced to move the same lateral distance. FIG. 20 is a schematic plan view of the hinge mechanism 200 and arms 201 of another embodiment of the invention. The secondary hinges 202 are shown disposed perpendicular to the primary hinge 203. The secondary hinges could be disposed at other orientations. A sprocket or pulley 204 is mounted on each secondary hinge 202 and adapted to rotate with the respective arms 201. A chain or belt 205 is looped about the pulleys in a "figure eight" configuration, causing the arms to rotate symmetrically in the lateral direction. Alternately, two chain or belt segments could be used, each following an S-shape, to form the figure eight. The belt may be non-defor able and require completely symmetrical movement of the arms, or may be made of an elastic material which would permit the arms to rotate asymmetrically but would encourage symmetrical movement. FIG. 21 is a partial schematic plan view of the hinge mechanism 210, arms 211 and handles 212 of another embodiment of the invention. The arms are mounted directly to the primary hinge 213. The arms may be angled outward. Handle rods 214 are mounted at the ends of the arms distal to the primary hinge 213. A handle is slidingly mounted to each handle rod. The user is thus free to select the width of his hands during the exercise stroke, even changing the position of the hands. FIGS. 21A-21F show schematic end views of the hinge mechanism 210, in the plane 215 of the arms 211. As shown in FIG. 21A, the handle rod may be oriented within the plane of the arms, providing a neutral- resistance sliding motion of the handles 212. In this plane, the handle rod may be slanted up away from the arm, slanted down away from the arm or disposed horizontally. Further, the handles may be tilted backward from plane 215, as shown in FIG. 21B, or tilted forward of plane 215, as shown in FIG. 21C, thereby resisting handle movement inward or outward respectively, as this movement raises the arms and acts against the resistance. As shown in FIGS. 21D, 21E and 21F, a resistance mechanism, such as springs 216-219, can be mounted to the handle rod 214 to oppose the movement of the handle 212 in the lateral direction. In the embodiment shown in FIG. 2ID, the resistance mechanism 216 opposes movement of the handles 212 outward. As shown in FIG. 21E, the resistance mechanism 217, 218 opposes movement of the handles 212 both inward and outward. As shown in FIG. 2IF, the resistance mechanism 219 opposes movement of the handles 212 inward. The resistance mechanisms 216-219 may be further supplemented by inclining the handle rods 214 as shown in FIGS. 21B and 21C. FIG. 22 is a front elevation view of the hinge mechanism 220, arms 221 and handles 222 of another embodiment of the invention. The arms 221 are mounted directly to the primary hinge 223. Preferably, the arms are angled outward. Handle rods 224 are mounted at the ends of the arms distal to the primary hinge and disposed on the interior side of the arms. A handle is slidingly mounted to each handle rod. The user is thus free to select the width of his hand position during the exercise stroke, and to vary the position of the hands throughout the exercise pattern. As shown in FIGS. 22A, 22B and 22C, the handle rod may be oriented within the plane 225 of the arms 221, or angled rearward from or forward of plane 225, to provide neutral, inward or outward resistance, respectively, to handle movement. As shown in FIGS. 22D, 22E and 22F, a resistance mechanism, such as springs 226-229, can be mounted to the handle rod to oppose the movement of the handle in the lateral direction. As shown in FIG. 22D, the resistance mechanism 226 opposes movement of the handles 222 outward. As shown in FIG. 22E, the resistance mechanism 227, 228 opposes movement of the handles 222 both inward and outward. As shown in FIG. 22F, the resistance mechanism 229 opposes movement of the handles 222 inward. The resistance mechanis s 226-229 may be further supplemented by inclining the handle rods 224 as shown in FIGS. 22B and 22C. FIG. 23 is a schematic front view of the hinge mechanism 230, arms 231 and handles 232 of another embodiment of the invention. The arms are mounted directly to the primary hinge. The arms may be angled outward. Handle rods 234 are mounted at the ends of the arms 231 distal to the primary hinge 233 and disposed on the exterior side of the arms. The handle rod may be oriented at a horizontal plane, tilted up away from the arm, or tilted down away from the arm. A handle 232 is slidingly mounted to each handle rod 234. A cable 235 is engaged to each handle and is directed, for example, by pulleys 236 and 237 up to the primary hinge 233 and down to a weight stack (see FIGS. 13A and 13B) such that the user may select the resistance to be provided to lateral movement of the arms. As shown in FIG. 23A, a detail view of the handle, the cable 235 is preferably disposed within the handle rod 234 and arm 231 to decrease the chance of the user contacting the cable. The handle rods 234 may alternatively be mounted to the interior side of the arm to provide resistance to inward motion of the arms. Further, the movement of the cables alternatively may be resisted by springs, friction, pneumatic, electric or magnetic resistance or other resistance mechanisms. FIG. 24 is a schematic plan view of the hinge mechanism 240 and arms 241 and 248 of another embodiment of the invention. A single secondary hinge 242 is mounted perpendicular to the primary hinge 243. An extension 244 is attached to one of the arms 241 opposite the secondary hinge. A pivot plate 245 is slidingly and pivotally mounted at its center 247 to the primary hinge 243. The extension 244 is pivotally mounted to one end of the pivot plate 245. A rigid link 246 is pivotally mounted to the other end of the pivot plate 245 and to the other arm 248. A four-bar linkage is created by the extension 244, the portion of the second arm 248 near the primary hinge, the rigid link 246 and the pivot plate 245. Lateral displacement of one of the arms causes lateral displacement of the other in the opposite direction, via the four bar linkage. FIG. 25 is a partial schematic view of the hinge mechanism 250 of another embodiment of the present invention that permits the user to select the orientation of the secondary hinges to the primary hinge, respectively. Since the orientation of the secondary hinge to the primary hinge controls the resistance ratio of longitudinal to lateral resistance, the user can employ this embodiment to select a resistance ratio best suited to his exercise needs. The secondary hinges 251 (left secondary hinge only is shown) are mounted to the primary hinge 252 by a variable position rod 253. The arm 254 is mounted to the secondary hinge 251 by U-shaped member 255 which, in turn, is rotatably mounted to the secondary hinge. The orientation of the secondary hinge 251 to the primary hinge 252 is maintained by the engagement of notched or serrated surfaces 256 and 257 mounted to the secondary hinge and the primary hinge. To vary the orientation of the primary hinge to the secondary hinge, the notched surfaces are removed from engagement, such as by loosening a locking mechanism 258 such as a wing nut or cam lock. Once disengaged, the secondary hinge may be rotated to a desired position. The locking mechanism 258 is then tightened, engaging the notched surfaces and locking the secondary hinge in position with respect to the primary hinge. Preferably, both secondary hinges are disposed at the same orientation with respect to the primary hinge such that both arms will require the same force to be displaced laterally. In certain of the above embodiments of a chest press exercise machine, such as that of FIG. 13, a weight stack 131 may be connected to the exercising means by a belt 132 extending over a pulley 133. FIG. 26 is a cross sectional view of a self-aligning pulley 270 for use with an exercise machine, such as the exercise machine of FIG. 13. The pulley is designed to align itself with the belt when either the frame or the belt is not perfectly aligned. Such a self-aligning pulley may be substituted for the traditional pulley used as the weight stack pulley 133 in the apparatus shown in FIG. 13. FIG. 27 is a cross sectional view of the pulley 270 of FIG. 26, taken through section XXVII-XXVII. The self- aligning pulley 270 has a hub 277 mounted to a bearing 273. As shown in FIG. 26, a channel 278 having side walls 279 and a bottom 280 is disposed at the circumference of the hub 277 and adapted to accept a belt 281. In use, the belt should lie flat against the bottom of the channel. These elements are conventional. In the self-aligning pulley 270 of FIG. 26, a shaft 271 having a novel design is mounted to the frame 272. The shaft 271 is preferably made from a mild tool steel such as SAE 1018. A bearing 273 is mounted over the shaft such that it is disposed symmetrically about the center of the shaft. The center of the shaft has a crowned portion 274 that presents a convex surface to the bearings. Spacers or locking rings 275 are disposed at the ends of the shaft 271 to prevent the bearing from slipping off the shaft. Alternatively, the shaft could be formed with integral flanges at each end. Wave washers 276, preferably made of hardened steel having some compressibility, are mounted to the shaft and disposed between each spacer 275 and the bearing 273. The wave washers bias the bearing away from the spacers and, thus, operate to urge the bearing toward the center of the convex surface. Other centering devices, such as 0-rings, could be substituted for the wave washers. While the self-aligning pulley 270 is shown in FIG. 26 mounted to a cylindrical portion of frame 272, which is fitted to an internal diameter of the shaft 271, the frame could alternatively have bores fitted to the external dia eters of the spacers 275 and still practice the invention. FIG. 28 is a cross sectional view of the self-aligning pulley 270 shown correcting for a misalignment. As shown, the frame 272 is misaligned from a horizontal axis 282. However, this apparatus would work equally well if the belt 281 were misaligned. If a traditional pulley were used, the belt 281 would ride, at least in part, on the side wall 279 of the channel 278. When the misalignment is severe, or over long periods of use, the belt would have a tendency to ride up over the side wall 279 completely, such that the belt would be completely out of the channel. The self- aligning pulley, however, compensates for misalignment by tilting about a plane extending through the center of the pulley. When misaligned, the belt 281 exerts a force on the pulley 270 that overcomes the bias of the wave washers 276 and causes the bearing 273 to slide over the crowned portion 274, resulting in the tilting of the pulley. The tilting of the pulley maintains the belt 281 in a flat position against the bottom 280 of the channel. The crowned portion 274, which is a surface of rotation, preferably maintains the pulley in a symmetrical position with respect to the center of the shaft so that the pulley will tilt, rather than simply slide. By compensating for belt misalignment, the self- aligning pulley 270 reduces maintenance costs by minimizing edge wear on the belt 281 and by reducing side loads on the bearing 273. Furthermore, the self-aligning pulley can reduce manufacturing costs by permitting increased alignment tolerances without sacrificing belt life and smoothness of operation. FIG. 29 is a perspective view of an incremental weight stack 70 for use with a selectorized exercise machine, such as the apparatus of FIG. 13. A flange or storage finger 73 (shown partly in phantom) is rigidly mounted to a flange 72, which in turn is attached to a weight stack brace 20 such as by bolting. Slotted holes (not shown) may be provided in the flange 72 for height adjustment. The flange finger extends proximate to the top weight plate 75. A stack or movement finger 74 is mounted to the top of the top weight plate 75. Incremental weights 76, having tracks such as axial bore 79 (shown in phantom) for receiving the fingers 73 and 74, are slidingly mounted on the flange finger 73. When the weight stack is lowered (i.e., in the rest position) , the tips of the frame finger 73 and the stack finger 74 are adjacent, almost touching. The incremental weights can be moved from the flange finger to the stack finger as desired. The tips of the fingers 73 and 74 may be rounded to provide for a smooth transfer of the incremental weights 76. Rubber or elastomer bumpers 77 can be mounted to the fingers to restrict the movement of the incremental weights on the fingers. Preferably, both fingers are slanted up toward the tips at approximately 5° from horizontal. This angle retains the incremental weights on the respective fingers while permitting the weights to easily slide from one finger to the other. When the user lifts the weight stack, he also must lift any incremental weights on the stack finger. The incremental weight stack 70 permits use of heavy plates on the main weight stack 23. For example, each plate on the main stack may weigh 20 pounds. Each incremental weight may be 5 pounds. If three incremental weights are mounted to the flange finger, the user can select the appropriate resistance in five-pound increments by sliding the appropriate number of weights to the stack finger. This allows the user to finely adjust the resistance at any point throughout the weight stack. Further, the manufacturer will save costs in manufacturing and assembling an exercise machine with the incremental weight stack due to the labor saved using a smaller number of plates. The foregoing is in no way a limitation on the scope of the invention which is defined by the following claims:

Claims: I claim: 1. An apparatus for performing a chest press comprising: a frame having a front end and a rear end; a bench mounted to the rear end of the frame; a primary bearing tube rotatably mounted to the frame which primary bearing tube is rotatable about a primary axis and disposed above the bench; a bracket rigidly mounted to the primary bearing tube; a secondary bearing tube rotatably mounted to the bracket which secondary bearing tube is rotatable about a secondary axis wherein the primary axis and the secondary axis are skew; an arm rigidly mounted to the secondary bearing tube; a handle mounted to the arm distal to the secondary bearing tube; and a post mounted to the arm proximal to the handle for mounting weight plates. 2. The apparatus of claim 1 further comprising at least one spacer mounted to the post. 3. An apparatus for exercising the muscles of the upper torso of a user comprising: a frame having a front end and a rear end; a bench mounted to the frame at the front end; a primary hinge mounted to the frame and disposed above the bench, which primary hinge is rotatable about a primary axis; a secondary hinge mounted to the primary hinge, which secondary hinge is rotatable about a secondary axis; an arm mounted to the secondary hinge; a handle mounted to the arm distal to the secondary hinge; and means mounted to the arm for resisting the displacement of the arm. 4. The apparatus for exercising of claim 3 wherein the secondary hinge is a first secondary hinge, the arm is a first arm and the handle is a first handle, further comprising: a second secondary hinge mounted to the primary hinge; a second arm mounted to the second secondary hinge; and a second handle mounted to the second arm distal to the second secondary hinge. 5. The apparatus of claim 4 further comprising means for constraining the movement of the arms such that the first arm and the second arm move symmetrically. 6. The apparatus of claim 3 wherein the resistance means comprises a weight mounted to the arm. 7. A method for performing a chest press with an apparatus having a primary hinge mounted to a frame, a secondary hinge mounted to the primary hinge, an arm mounted to the secondary hinge, the method comprising: mounting a selected amount of weight to the arm; grasping the handle; pushing the handle away from the user; selecting a path of handle motion having a lateral motion component and a longitudinal motion component; rotating the primary hinge; and overcoming the selected amount of weight over the path of the handle motion. 8. The method of claim 7 wherein the step of pushing the handle includes rotating the secondary hinge. 9. The method of claim 8 wherein the step of rotating the secondary hinge causes the primary hinge to rotate. 10. The method of claim 7 wherein the step of overcoming the resistance comprises: overcoming resistance to the lateral motion component; and overcoming resistance to the longitudinal motion component. 11. An apparatus for performing a chest press comprising: a frame; a bench mounted to the frame; a primary hinge mounted to the frame; a secondary hinge mounted to the primary hinge; an arm mounted to the secondary hinge; a handle mounted to the arm distal to the secondary hinge; and means for resisting the displacement of the handle, said means being mounted to the arm. 12. The apparatus of claim 11 further comprising a foot brace mounted on to the bench. 13. The apparatus of claim 11 wherein the primary hinge is positioned on the frame above the bench. 14. The apparatus of claim 11 further comprising a post mounted to the arm wherein the resisting means comprises a weight plate mounted to the post. 15. The apparatus of claim 11 wherein the secondary hinge is oriented at 115 degrees with respect to the primary hinge. 16. The apparatus of claim 11 wherein the secondary hinge is a first secondary hinge, the arm is a first arm and the handle is a first handle, further comprising: a second secondary hinge mounted to the primary hinge; a second arm mounted to the second secondary hinge; and a second handle mounted to the second arm distal to the second secondary hinge.

Inventors: SIMONSON ROY, SIMONSON, ROY
Applicants: LUMEX, LUMEX, INC.
Application year: 1996
Main classification: A63B21
IPC codes: A63B21, A63B23