Patent Description:
Strengthening the human upper body has long been a popular activity. Long ago, the activity was practiced using a dumbbell which consisted of a short bar equipped with a weight on each end, and formed with a grip portion in the middle of the bar. The weightlifter could grasp the grip portion and focus training on specific muscle groups. For instance, by standing with the dumbbell at the waist, and bending the elbow to "curl" or raise the wrist and forearm upwards, the biceps are strengthened. Also, by standing with the dumbbell behind the weightlifter's shoulder with the elbow bent, pushing the dumbbell upwards strengthens the triceps. By lying on his/her back and holding the dumbbell directly above the chest, pushing up towards the sky in what is called a "press" strengthens the triceps, pectoral, and other major muscle groups. Other strengthening exercises are well known in the art which may utilize one dumbbell or a pair of dumbbells----one in each hand.

In addition to the dumbbells which have been used for many years, so too has the barbell. A barbell consists of an elongated bar formed with a pair of grip portions in roughly the middle of the bar for grasping with the weightlifter's two hands, and equipped with a weight receiver on each end of the bar. By placing weights of different sizes on the weight receivers, a barbell of different weights could be constructed. Similar exercises to those completed with the dumbbells discussed above can also be performed with a barbell. For instance, by standing up with the barbell at the weightlifter's waist and bending the elbows to raise the barbells upwards, a "curl" is performed strengthening the forearms and biceps. Similarly, with the weightlifter lying down and pushing the barbell upwards from the chest, a "press" is performed thereby strengthening the triceps and pectorals.

Because the weights placed on a barbell can be very heavy, it is important to have a proper grip on the grip portion of the barbell. During exercise routines, it is also important that the weightlifter's grip be consistent with the exercise being performed. For instance, the grip in a curl exercise may be very different from an exercise in a press exercise.

However, the grip portion of the conventional barbell is fixed as part of a rigid steel bar, and often perfectly linear. As a result, even though the grip portion may be in a proper position for a weightlifter at the start of the exercise, it is likely that the fixed grip portion of the barbell will be in a non-optimal position during at least a portion of the exercise. For instance, when performing a curl exercise with a barbell having a linear bar and fixed grip portion, the weight lifter's hands are in an acceptable position at the start of the exercise. However, as the barbell is raised upwards, the wrist has a tendency to rotate as the elbow bends upwards. Because the grip portion of the barbell is fixed, there is a significant amount of strain placed on the weightlifter's wrist and forearm. This strain can result in injury caused by excessive torsion on the wrist and forearm, including pulled muscles, strained ligaments, and other injuries requiring orthopedic treatment.

Several attempts to overcome the shortcomings of a straight-bar barbell follow the approach of the supinating barbell disclosed in <CIT>. The Metz barbell incorporates a pair of circular housings mounted to the bar which supports hand grips mounted for rotation within the housings. In many such devices, the hand grips can freely rotate to accommodate the change in wrist position as the barbell is raised and lowered. Other devices, such as the Metz barbell incorporate a friction mechanism between the grip and the housing to adjust the resistance to rotation of the hand grips from no resistance to a locked engagement. The same friction resistance concept has been incorporated into wrist and forearm exercise devices, such as the rotational exerciser shown in <CIT>. <CIT> provides Weightlifting apparatus, especially for performing curling exercises, including a rectangularly shaped frame having weights mounted on opposite extremities thereof.

An exercise bar assembly is provided that comprises a pair of rotating grip assemblies, each grip assembly including a generally planar frame and a hand grip mounted within the frame for rotation within in the plane of the frame. A center bar assembly defining a longitudinal axis and opposite ends along the longitudinal axis, is fixed at its opposite ends to the frame of the rotating grip assemblies along the longitudinal axis. A pair of plate bar assemblies are also fixed to the frame of the rotating grip assemblies along the longitudinal axis.

In one feature of the disclosure, an elastic element is engageable between the pair of rotating grip assemblies along the longitudinal axis. The elastic element can comprise an elongated elastic band having a spring constant for resisting rotation of the hand grip in each of the rotating grip assemblies. Each of the pair of rotating grip assemblies include a ring plate defining a circumference and rotatably mounted in the frame for rotation within the plane of the frame. The ring plate carries the hand grip and can be rotated at least between a position in which the hand grip is perpendicular to the longitudinal axis and a position in which the hand grip is aligned with the longitudinal axis.

In a further feature of the disclosure, a plurality of bearing posts project perpendicularly from the ring plate, with one bearing post arranged on the ring plate to be aligned with the longitudinal axis when the hand grip is perpendicular to the longitudinal axis. Another bearing post is arranged <NUM> degrees opposite the one bearing post. The other bearing posts are spaced <NUM> degrees apart from the one bearing post around the circumference of the ring plate. The elongated band includes a collar at each end thereof that is configured to be mounted on any of the bearing posts of each of the pair of rotating grip assemblies. When the elongated band is mounted on the one bearing post, for instance, manual rotation of the hand grips, and thereby rotation of the rotating grips assemblies, causes the elastic band to contact successive ones of the bearing posts in the direction of rotation of the hand grip.

In a common weight training exercise, the curl, rotation of the wrist is done by the forearm and assisted by bicep until arm has bent to <NUM> degrees. During further curl movement after reaching <NUM> degrees, the bicep alone controls the forearm. When the bicep contracts it pulls the forearm up and naturally rotates it outward naturally. If the wrist is not allowed to rotate the bicep cannot contract fully. The rotating grip assemblies of the exercise bar assembly disclosed herein allow for the full range of motion of the bicep, and the elastic band creates a resistance exercise through the bicep's full range of motion.

For the purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated in the drawings and described in the following written specification. It is understood that no limitation to the scope of the disclosure is thereby intended. It is further understood that the present disclosure includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles disclosed herein as would normally occur to one skilled in the art to which this disclosure pertains.

An exercise bar assembly <NUM> shown in <FIG> includes a pair of plate bar assemblies <NUM> that can be weighted and/or configure to receive conventional weight plates. The length of the plate bar assemblies <NUM> depends on the intended use of the bar assembly, and in particular the amount of weight expected to be carried by the bar assembly. A length of <NUM>,<NUM>-<NUM>,<NUM> (<NUM>-<NUM> inches) is typical. Each plate bar assembly is fastened to a rotating mount assembly <NUM>, and in particular to a rigid generally planar frame <NUM> of the mount. The frames of the two rotating mount assemblies <NUM> are connected to each other by a center bar assembly <NUM>. The combination of the plate bar assemblies <NUM>, center bar assembly <NUM> and the frames <NUM> form the barbell. Thus, the assembly of these components must be strong enough to support the weight carried by the plate bar assemblies <NUM> during use of the exercise bar assembly <NUM>. The center bar assembly <NUM> has a length that is sized to locate the rotating mount assemblies at an ideal location for the person to comfortably lift the bar assembly during a workout. Nominally, the person will grasp a conventional barbell with the hands roughly shoulder-width apart. Some weight-lifting exercises require the grip positions to be moved inboard or outboard. As described herein, the present disclosure contemplates that the center bar assembly can be provided in different lengths to provide different grip positions.

The rotating assemblies mounts <NUM> support hand grips <NUM> for rotation in the plane of the frames <NUM>. The hand grips <NUM> are conventionally sized to be comfortably grasped by the user. As described in more detail herein, a bearing assembly supports each of hand grips within its corresponding frame and permits smooth rotation of the grips relative to the frame. Each rotating mount assembly <NUM> includes a plurality of bearing posts 28a-28f projecting from one side of the mount, as shown in <FIG>. In one important feature of the bar assembly <NUM>, an elastic band <NUM> includes a mounting collar <NUM> on each end that is adapted to be mounted on a bearing post on the two rotating mount assemblies <NUM>. The elastic band spans between the two rotating grip assemblies <NUM> over the center bar assembly <NUM>. As can be readily appreciated, the elastic band <NUM> provides elastic resistance to rotation of the hand grips <NUM> relative to the corresponding frames <NUM>. The elastic band <NUM> can be in several forms, such as a resistance work-out band or a bungee cord, with a predetermined resistance against elongation or a predetermined spring constant. The band must be capable of repeated extension and elastic retraction without failure and preferably incorporates an outer surface capable of low-friction engagement with the bearing posts, as described herein. In one embodiment, shown in <FIG>, the bearing posts include a spool 29a rotatably mounted on a post 29b, that is in turn mounted to the frame by a threaded post 29c. The spool 29a defines a recess to receive the elastic band, as described below. Since the elastic band is intended to provide resistance against rotation of the hand grips, the rated force of the band is less than for a conventional work-out resistance band. In one specific embodiment, the elastic band can have a spring constant to achieve rated force of ten pounds at a maximum elongation of about <NUM>%.

In a baseline position, the hand grips are oriented perpendicular to the longitudinal axis L along the length of the bar assembly, as depicted in <FIG>. The mounting collar <NUM> of the elastic band <NUM> is mounted on the baseline bearing post 28a, as shown in <FIG>, and held in place by a snap ring <NUM> (<FIG>). In this baseline position, the elastic band is at its neutral, unstretched length. When the two hand grips are rotated <NUM>° from this baseline position, or first starting position, as shown in <FIG>, the elastic band is stretched because the mounting collars <NUM> at the end of the band are carried with the bearing post 28a as the respective rotating mount assemblies <NUM> are rotated. As the hand grips are rotated, the elastic band first engages one of the fixed bearing posts <NUM> and then engages the next successive bearing post 28e for a counter-clockwise rotation of the left-hand grip and a clockwise rotation of the right-hand grip. It can be appreciated that when executing a curl, the wrists have a tendency to rotate outward as the bar assembly is lifted. The length of the elastic band increases as the position of the bearing posts on which mounting collars are engaged move circumferentially with the rotation of each rotating mount assembly <NUM>. The change in length is roughly equal to ¼ the circumference of the rotating mount assembly for a <NUM>° rotation of one the hand grips, or double that value for rotation of both hand grips. Thus, in the illustrated embodiment of <FIG>, the elastic band is elongated about <NUM>%.

As shown in <FIG>, each rotating mount assembly <NUM> includes a plurality of bearing posts distributed around the circumference of the mount. In the illustrated embodiment, seven bearing posts are provided, with posts 28a and 28d oriented along the longitudinal axis L of the bar assembly, and <NUM>° opposite each other. Two bearing posts 28b, 28c are spaced at <NUM>° intervals in the counter-clockwise direction on the left-side rotating mount assembly from the baseline post 28a (or clockwise on the right-side mount). Two bearing posts 28e and 28f are spaced at <NUM>° intervals in the clockwise direction on the left-side rotating mount assembly from the baseline post <NUM> (or counter-clockwise on the right-side mount). These additional mounts engage the elastic band <NUM> as the rotating mount assemblies are rotated so that the band is stretched across the posts, as shown in <FIG>. In addition to this feature, the additional mounts provide a different mounting point, or starting point, for the collar <NUM> of the elastic band <NUM>, which allows the user to vary the resistance force at the <NUM>° rotation of the and grips <NUM>. Thus, as shown in <FIG>, the mounting collar <NUM> of the elastic band <NUM> can be mounted on the bearing mount 28b, instead of the baseline bearing mount 28a. With the elastic band anchored at this second starting location, the <NUM>° rotation of the hand grip stretches the band <NUM> essentially <NUM>° farther around the circumference of the rotating mount assembly than when starting at the baseline position 28a. With the starting position of the elastic band on the bearing mounts 28b, the <NUM>° rotation of the hand grip elongated the elastic band by about <NUM>%. The full elongation of the elastic band (about <NUM>%) can be achieved if the collars <NUM> of the elastic band are mounted on the bearing mounts 28c at the third starting location shown in <FIG>. On the other hand, the minimal elongation is achieved by placing the band mounting collars on the bearing posts 28d, as shown in <FIG>. In this fourth starting position, the <NUM>° rotation of the hand grip <NUM> does not draw the elastic band <NUM> across any other bearing mount, as in the previous positions. The elongation of the band is less than the elongation shown in <FIG> because the band is not drawn across the bearing post 28f. The band is elongated about <NUM>% when mounted to posts 28d.

It should be understood that the exercise bar assembly <NUM> of the present disclosure can be used to perform the full range of arm exercises and lifts. The rotating mount assembly <NUM> for the hand grips <NUM> allows the grips to rotate as the arm is lifted or lowered, in accordance with the natural physiology of the wrists and forearms. The incorporation of the elastic band <NUM> between the rotating mount assemblies adds resistance to the natural forearm rotation, which in turn adds another level to the arm exercise. The user can adjust the amount of resistance to rotation by mounting the elastic band on different bearing posts, thereby varying the elongation from <NUM>% to <NUM>%. The user can also adjust the amount of resistance by selecting from a plurality of elastic bands having different spring constants or rated forces. The elastic band <NUM> can be easily removed and replaced with a different elastic band.

The bar assembly <NUM> also allows the user to rotate the hand grips inward - i.e., clockwise with the left hand and counter-clockwise with the right hand - to provide a negative bicep workout. For this type of workout, the elastic band <NUM> is mounted on the posts 28f so that the grips <NUM> are parallel to the bar axis L. Rotation of the hand grips draws the elastic band down across the lower fixed post <NUM> and across the bearing post 28e until the hand grip is in the perpendicular position. The elastic band is elongated as the left rotating mount <NUM> rotates clockwise and the right mount rotates counterclockwise.

Further features of the exercise bar assembly <NUM> are shown in <FIG> and <FIG>-<NUM>. The rotating grip assemblies <NUM> include a plurality of support posts <NUM> projecting from the top side of the frame <NUM> of each assembly, and a like plurality of posts <NUM> projecting from the bottom side of the frames, as best seen in <FIG>. The support posts are sufficiently tall for the bar assembly to be supported on a surface, such as the floor, with clearance for the plate bar assemblies <NUM> and the bearing posts <NUM>. The support posts <NUM>, <NUM> allow a user to perform push-ups with the exercise bar assembly <NUM> sitting on the floor. In this respect, the bar assembly <NUM> works like a push-up disc known in the art. However, the elastic band <NUM> between rotating mount assemblies adds a feature not found in the conventional push-up discs. In one embodiment, the support posts can include a stud <NUM> into which is threaded a mounting screw <NUM>. The mounting screw is in turn threaded into a bore <NUM> defined in the frame <NUM> of the rotating mount assembly <NUM>. This allows the support posts <NUM>, <NUM> to be removed as desired. The stud can have a hex configuration for engagement with a wrench or can include some other feature to be engaged by a driving tool.

In one embodiment, the exercise bar assembly <NUM> allows the rotating grip assemblies <NUM> to be separated by different distances to provide different grip locations. As mentioned above, for a conventional bicep curl, the exercise bar is optimally gripped at shoulder width. Of course, shoulder width varies among users, so while a grip spacing of <NUM>,<NUM> (<NUM> inches) may be comfortable for many users, shorter or taller users may require different grip spacing. In addition, different exercises require different grip locations, inside and outside shoulder-width, to work different muscle groups. Thus, in one aspect of the present disclosure, the exercise bar assembly <NUM> can be provided with an adjustable or modifiable center bar assembly <NUM> spanning the space between the two rotating handle assemblies <NUM>. In particular, the center bar assembly <NUM> includes a center bar <NUM> that can be provided in different lengths. In particular, the user can select from several center bars <NUM> of different lengths to find a suitable grip width.

Each center bar <NUM> is configured to be removed from the center bar assembly <NUM> for ready replacement. Thus, in one embodiment, the center bar <NUM> includes snap ring grooves <NUM> adjacent the opposite ends of the bar, as shown in <FIG>. The grooves are configured to receive a snap ring <NUM>. The assembly further includes a pair of collars <NUM> arranged at the opposite ends of the center bar <NUM>, each defining a bore <NUM> through which the center bar extends. The end of the collars facing the center bar define a circumferential flange <NUM> that is sized to trap the snap rings <NUM> within the collars, thereby locking the collars <NUM> to the center bar <NUM>. It can be appreciated that the collars and center bar can be assembled by first introducing one end of the center bar <NUM> into the bore <NUM> of one collar with the snap ring groove <NUM> accessible at the opposite end of the collar for engagement of the snap ring <NUM>. Once the snap ring is engaged, the first collar can be slid to the end of the rod so that the second collar can be slid onto the second end of the rod. The second end is accessible outside the bore <NUM> of the second collar for engagement of the snap ring <NUM> with the groove at the second end of the rod, thereby fixing the second collar to the rod.

In can be appreciated that this intermediate assembly of the center rod <NUM> and the two collars <NUM> is a loose assembly since the collars are free to slide along the rod, although they are prevented from becoming disengaged by the snap rings <NUM>. The center bar assembly <NUM> thus includes a mounting element <NUM> that is configured to fix the intermediate assembly to the frames of the respective rotating grip assemblies <NUM>, while simultaneously pushing the snap rings <NUM> against the end flanges <NUM> of the two collars <NUM>. The mounting element <NUM> includes an outboard stud <NUM> that is configured for a close-fit with a bore <NUM> defined in an end face <NUM> of the frame <NUM>. In one embodiment, the outboard stud <NUM> and bore <NUM> define complementary shapes, such as the triangular shape shown in <FIG>. The stud <NUM> is pressed into the bore <NUM> and held in place by a set screw <NUM> threaded through a threaded bore <NUM> that intersects the bore <NUM>. The element <NUM> further includes a conical end face <NUM> that is configured to engage a complementary conical surface <NUM> in each end of the center rod <NUM>. An inboard stud <NUM> projects from the conical end face <NUM> and is configured to be seated in a complementary shaped bore <NUM> in each end of the rod <NUM>. The inboard stud <NUM> and complementary bore <NUM> can have a non-circular shape, such as the triangular shape shown in <FIG>. It can thus be appreciated that the center bar <NUM> is fixed against rotation along its axis by way of the non-circular interfaces between the studs <NUM>, <NUM> and their respective complementary bores <NUM>, <NUM>.

The assembly is clamped together by a threaded portion <NUM> of the component <NUM> that threads into a threaded end (not shown) of the bore <NUM> of the collar <NUM>. The collar is not constrained against rotation, so it can be rotated to thread itself onto the threaded portion <NUM> of the rotationally fixed component <NUM>. The exterior of the collar <NUM> can be configured to receive a tool, such as a wrench, or can include knurling or some other grip enhancing feature that permits manual tightening. The threads can be self-locking threads so that the components of the center bar assembly <NUM> remains rigidly coupled during use of the bar assembly <NUM>. As the collar is threaded onto the threaded portion <NUM> of the mounting element <NUM> the inboard stud <NUM> engages the complementary opening <NUM> in the center bar <NUM> and the conical end face <NUM> engages the conical surface <NUM> of the bore. Continued rotation of the collars <NUM> gradually clamps the center bar <NUM> between the mounting elements <NUM>, forming a rigid connection between the center bar and the two rotating grip assemblies <NUM>.

It can be appreciated that this assembly <NUM> allows a user to easily replace the center bar <NUM> with a bar of different length in order to adjust the grip width for the exercise bar assembly <NUM>. In one embodiment, the assembly <NUM> is provided to the user as a completed assembly with the mounting elements <NUM> at the ends of the center bar assembly free to be placed with the respective openings <NUM> in the left and right frames <NUM>. Additional assemblies with longer center bars <NUM> can be provided to the user in a completed assembly. Alternatively, the user can be permitted to disassemble the center bar assembly <NUM>, by first unthreading the two collars <NUM> from the threaded portion <NUM> of the mounting elements <NUM> so that the center bar and collars can be removed. One collar is slid down the center bar toward the opposite end to expose one of the snap rings <NUM> for removal. The associated collar is removed and the other collar slid down the center bar to expose the other snap ring for removal. The process can be reversed to add a new center bar <NUM> to the assembly <NUM>.

The plate bar assemblies are also configured to be removed from the exercise bar assembly <NUM>. It can be appreciated that the plate bar assemblies <NUM> and the center bar assembly <NUM> can be removed from the rotating grip assemblies <NUM> to break down the entire exercise bar assembly <NUM> for storage or transport. In addition, removing the plate bar assemblies can essentially convert the remainder of the exercise bar assembly <NUM> to a wrist/forearm exercise apparatus rather than a weight lifting apparatus.

The plate bar assembly <NUM> includes an inner bar <NUM> with a threaded end <NUM> for engagement with a threaded bore <NUM> in the frame <NUM> of each rotating grip assembly <NUM>. The inner bar includes bearing seats <NUM> at the opposite ends of the bar to receive bearings <NUM>. The bearings abut a shoulder <NUM> of the inner bar, with one bearing held in place between the shoulder and an end face <NUM> of an anchor cap <NUM>, and the other bearing held in place against the shoulder by a snap ring <NUM> fixed in a snap ring groove <NUM> at the outboard end of the bar <NUM>. It can be understood that the anchor cap <NUM> is trapped between the inner bar <NUM> and the face of the frame <NUM> when the threaded end <NUM> of the inner bar <NUM> is threaded into the bore <NUM>.

The plate bar assembly <NUM> further includes an outer bar <NUM> having a bore <NUM> sized to fit over the inner bar, and in particular to have a close running fit with the outer surfaces of the bearings <NUM>. The outer bar <NUM> includes a threaded end <NUM> that is configured to engage internal threads <NUM> of the anchor cap <NUM>. The outer bar <NUM> can be fixed to the inner bar <NUM> by way of the threaded engagement with the anchor cap <NUM>, with the anchor cap in turn fixed to the frame <NUM> by the threaded engagement of the inner bar <NUM> with the frame. A cover plate <NUM> covers the bore <NUM> and is held in place by a snap ring placed within groove <NUM> at the end of the outer bar.

The rotating grip assemblies <NUM> include a ring plate <NUM> that includes the handle <NUM> spanning a center opening <NUM> of the plate. The center opening <NUM> is sized so that a user can easily grasp the grip <NUM> with sufficient clearance to avoid contacting the ring plate <NUM>. In one embodiment, the center opening can have a diameter of <NUM>,<NUM>- <NUM>,<NUM> (<NUM>-<NUM> inches). The ring plate is configured to be received for free rotation within the circular opening <NUM> in the frame <NUM>. The upper and lower perimeter of the ring plate define a bearing channel <NUM>. The assembly further includes upper and lower bearing assemblies <NUM> that include a plurality of ball or roller bearings <NUM> contained within a circular cage <NUM>. The ball bearings are configured for rolling movement within the bearing channels <NUM> on the top and bottom faces of the ring plate. The ring plate and bearing assemblies <NUM> are held in place within the opening <NUM> of the frame by outer race plates <NUM>. The outer race plates each define a bearing channel <NUM> to receive the ball bearings <NUM> of the bearing assemblies. The outer race plates <NUM> are fastened to a mounting flange on each side of the frame <NUM>, such as by bolts or other conventional fasteners. The ring plate <NUM> and the two bearing assemblies <NUM> are thus sandwiched between the two outer race plates <NUM> so that the ring plate, and therefore the hand grip <NUM>, is free to rotate within the frame. It can be appreciated that the bearing posts 28a-28f are mounted to the upper face of the ring plate <NUM> of each rotating mount <NUM>.

The present disclosure should be considered as illustrative and not restrictive in character. It is understood that only certain embodiments have been presented and that all changes, modifications and further applications that come within the disclosure are desired to be protected. For instance, the center bar assembly <NUM> can be replaced with a single center bar that integrates the mounting element <NUM> into the ends of the bar. Alternatively, the center bar assembly can be replaced with a single bar that is integral with the two frames <NUM>. Likewise, the plate bar assemblies <NUM> can each constitute a single bar with the threaded end <NUM> for engagement with the threaded bore <NUM> in each frame. Alternatively, the plate bar assemblies can be replaced with a single bar that is integral with the two frames.

Claim 1:
An exercise bar assembly (<NUM>) comprising:
a pair of rotating grip assemblies (<NUM>), each including a generally planar frame (<NUM>) and a hand grip (<NUM>) mounted within the frame for rotation in the plane of the frame;
a center bar assembly (<NUM>) defining a longitudinal axis (L) and opposite ends (<NUM>) along the longitudinal axis, each of the opposite ends (<NUM>) fixed to said frame (<NUM>) of a corresponding one of the rotating grip assemblies (<NUM>) along the longitudinal axis (L); and
an elongated elastic element (<NUM>) having opposite ends (<NUM>), each of said opposite ends having a mounting collar (<NUM>) engageable to a bearing post (28a-f) on a corresponding one of said pair of rotating grip assemblies (<NUM>) and extending along said longitudinal axis (L) between said pair of rotating grip assemblies (<NUM>), said elastic element (<NUM>) resisting rotation of said hand grip (<NUM>) in each of the rotating grip assemblies (<NUM>),
characterized in that each of said rotating grip assemblies (<NUM>) includes at least one fixed bearing post (<NUM>), separate from said bearing post (28a-f), projecting perpendicularly from said frame (<NUM>) and arranged on said frame (<NUM>) to contact said elastic element (<NUM>) upon rotation of said hand grip (<NUM>).