Abstract:
The invention is for a tub grip for a bathtub that assists bathers in entering and exiting a bathtub. The tub grip is sturdy and easy to attach and remove for those that may suffer from loss of strength and dexterity due to advanced age, injury, illness, or other medical condition. In addition, the tub grip is constructed to resist wear and tear and provide its users with a substantial service life. One embodiment of the invention comprises a locking member, a first arm assembly, a clamp assembly, a second arm assembly, and, at least one locking plate. The first and the second arm assemblies and the locking plate are mounted on the locking member, whereas the clamp assembly is attached to the locking member. The locking member comprises a plurality of teeth, to which the locking plate is selectively engageable.

Description:
BACKGROUND OF INVENTION  
       [0001]     This invention generally relates to bathtub safety devices.  
         [0002]     More specifically, the invention relates to removable tub grips that can be secured to a bathtub to assist bathers entering and exiting the bathtub.  
         [0003]     It is well known that entering and exiting a bathtub can be hazardous to a bather. The typical home bathroom setting often includes items made from porcelain, hard plastics, tile, and other like materials. The surfaces of such materials are known to become slippery when wet. Typically a bather has to step over a bathtub wall to enter and exit a bathtub. This causes the bather to maintain balance on one foot while the foot is located on a potentially wet and slippery surface. The challenge of entering and exiting a bathtub is exacerbated when the bather&#39;s balance is impaired due to advanced age, injury, illness of other medical condition.  
         [0004]     One method of greatly reducing the hazards to bathers is to provide a sturdy device for the bather to manually grasp, to assist in maintaining balance and stability, while entering and exiting a bathtub. This type of device is generally referred to as a tub grip. Nearly all bathtubs have at least one portion that is unimpeded by obstacles, such as the walls of the room, by which the bather enters and exits the bathtub. One common arrangement for providing a sturdy support is to attach such a support to an unimpeded portion of the bathtub. This provides a device that supplies stability where it is most needed and can be most conveniently utilized by the bather.  
         [0005]     In general, there are deficiencies in existing tub grips that can be traced to the functionality and design of current devices. One such deficiency is the lack of overall strength and stability of present tub grips. The stability of current devices is undermined by the method of attachment. Attachment methods typically rely on a user&#39;s strength and dexterity to secure the tub grip to a bathtub wall. One such attachment method utilizes a threaded rod, with one end attached to a knob and the other end passing through a nut that is secured within the tub grip. The user attaches the device to the bathtub wall by manually turning or twisting the knob, which moves one or more sections of the tub grip into contact with the bathtub wall to form an attachment. This process, and others like it, provide profound challenges to users that lack the hand strength, due to advanced age, injury, illness, or other medical condition, to perform such an operation. Any requirement above using a mild manual force to attach and detach a tub grip renders the tub grip unusable for a portion of the population.  
         [0006]     Another deficiency in current tub grips is the limited number of times that a tub grip can be attached and detached from a bathtub wall before the device is rendered ineffective due to wear and tear of components. The numerous attachments and detachments, coupled with the relatively large forces needed to secure the tub grip to a bathtub wall, cause components to deform and fail over time. These failures erode the usefulness of the device over time.  
       SUMMARY OF INVENTION  
       [0007]     The invention is for a tub grip for a bathtub that is sturdy and easy to attach and remove for those that may suffer from loss of strength and dexterity due to advanced age, injury, illness or other medical condition. In addition, the tub grip is constructed to resist wear and tear and provides its users with a substantial service life. One embodiment of the invention comprises a locking member, a first arm assembly, a clamp assembly, a second arm assembly, and, at least one locking plate. The first and the second arm assemblies and the locking plate are mounted on the locking member, whereas the clamp assembly is attached to the locking member. The locking member comprises a plurality of teeth, to which the locking plate is selectively engageable. 
     
    
     BRIEF DESCRIPTION OF DRAWINGS  
       [0008]     The present invention will be more fully understood by reference to the following detailed description of the invention and the accompanying drawings. The drawings represent exemplary embodiments of the present invention and are included for illustrative purposes in order to facilitate understanding of the description. Other embodiments of the present invention contemplated by the description are included within this application to the extent they fall within the scope of the claims attached hereto.  
         [0009]      FIG. 1  is an exemplary perspective view of a tub grip.  
         [0010]      FIG. 2  is an exploded view of the tub grip in  FIG. 1 .  
         [0011]      FIG. 3  is an exemplary perspective view of the internal configuration of tub grip.  
         [0012]      FIG. 4  is an view similar to  FIG. 3  with the clamp lever actuated.  
         [0013]      FIG. 5  is an exemplary perspective view of relationship between locking member, locking plate, and locking plate spring.  
         [0014]      FIG. 6  is an exemplary perspective view locking plate release mechanism.  
         [0015]      FIG. 7  is an cross-sectional side view of tub grip.  
         [0016]      FIG. 8  is a cross-sectional side view detailing locking plates, locking member, locking surface, and locking plate spring.  
         [0017]      FIG. 9A  is an illustrative view detailing the geometric relationship of teeth of the locking member. 
     
    
     DETAILED DESCRIPTION  
       [0018]     The preferred embodiment of a tub grip  100 , as shown in  FIG. 1 , includes a handle assembly  102 , a first arm assembly  104 , a second arm assembly  106 , a clamp assembly  108 , a locking member  202 , a pair of locking plates  204 ,  206 , and a locking plate release mechanism  602 . So configured, the tub grip can be removably secured to a bathtub to assist bathers in entering and exiting the bathtub.  FIG. 2  shows an exploded view of the preferred embodiment.  
         [0019]     The clamp assembly  108  is pivotally attached to an end portion of the locking member  202 . The clamp assembly  108  is comprised of a clamp lever  208  and a cam  226 . The first arm assembly  104  is mounted on the locking member  202 , proximate to the clamp assembly  108 . The first arm assembly comprises a first arm assembly housing  212 , removably coupled to a pressure plate  210 , and a first arm assembly pad  220  attached to the first arm assembly housing  212 . The mounting of the first arm assembly is achieved by passing the locking member  202  through an aperture in the pressure plate  210 .  
         [0020]     The locking member  202  can be any structural component that has a large ratio of length of the component as compared to its height or diameter. In the preferred embodiment the member  202  has an approximately rectangular cross-section, where the cross-sectional height is substantially larger than the width. Views of the locking member of the preferred embodiment can be seen in figures  2  through  6 .  
         [0021]     The second arm assembly  106  is slidably mounted on the locking member  202 . Slidably mounted refers to the locking member  202  constraining the arm  106  in two directions of movement while allowing freedom of movement in a third direction, where the third direction is along the length of the locking member  202 . This configuration allows for the position of the second arm assembly  106  to be adjusted with respect to the first arm assembly  104 .  
         [0022]     The pair of locking plates  204 ,  206  are slidably and titlably mounted on the locking member  202 . The plates  204 ,  206  are placed in contact with one another and located within the length of the locking member  202  that is occupied by the second arm assembly  106 . Titlably mounted refers to the ability of a plate  204  to rotate a given amount, with respect to the length of the locking member  202 . The plates  204 ,  206  are mounted by passing the locking member  202  though apertures in the locking plates  204 ,  206 . The ability to tilt or rotate is achieved by the aperture in a plate  204  having a height that is greater than the height of the locking member  202 . Although the preferred embodiment employees two locking plates  204 ,  206 , the invention is not limited to two. The invention can utilize one locking plate or numerous locking plates.  
         [0023]     In general, the method of securely attaching the tub grip to a bathtub, in the preferred embodiment, relies on positioning the first arm assembly  104  in contact with one side of a bathtub wall and adjusting the position of the second arm assembly  106 , by sliding the second arm assembly  106  along the locking member  202  and towards the stationary first arm assembly  104 , until the second arm assembly  106  is in contact with an opposing side of the bathtub wall. Once the arm assemblies  104 ,  106  are in position, the tub grip applies an adequate clamping force to the bathtub wall to form a secure attachment and bear the weight of a bather entering and exiting the bathtub.  
         [0024]     The positioning of the second arm assembly  106  can be enabled by a ratcheting mechanism. A ratcheting mechanism generally allows a component to have relative motion in only one direction, with respect to a second component. In the preferred embodiment of this invention, the ratcheting mechanism allows the second arm assembly  106  to move towards the first arm assembly  104  and resists movement away from the first arm assembly  104 . In positioning the second arm assembly  106  a bather can use manual force to move the second arm assembly  106  towards the wall of the bathtub until the there is sufficient clamping force to secure the tub grip  100  to the bathtub wall. In some cases, this process may generate an attachment sufficient to support the weight of a bather entering and exiting a bathtub.  
         [0025]     In cases where the attachment is not sufficient to support the weight of the bather the clamping force can be enhanced by the clamping assembly  108 . The claming force is enhanced when the clamping assembly  108  draws the second arm assembly  106  towards the first arm assembly  104 . This is achieved when the clamp lever  208  is moved from a horizontal position to a vertical position. The clamping assembly  108  transfers rotational motion and force into linear motion and force. In addition, the lever provides a mechanical advantage to the user. A downward force placed on the lever is multiplied as it is converted to a linear force. This resultant linear force is normally greater than a force the user could manually apply directly to second arm assembly  106 .  
         [0026]     While the user positions the second arm assembly  106 , the clamp lever  208  is normally in a horizontal position, as shown in  FIG. 3 . The clamp assembly  108  is actuated by applying a downward force on the clamp lever  208 , which pivots with respect to the locking member  202 , and moving the lever  208  to a vertical position, as is shown in  FIG. 4 . The lever  208  is coupled to a cam  226 , which is in contact with first arm assembly  104 , via the pressure plate  210 . As the clamp lever  208  is moved downward, the interaction of the cam  226  on the stationary pressure plate  210  causes the locking member  202  to move towards the clamping assembly  108 . This causes the second arm assembly  106  to move towards the first arm assembly  104 , which increases the clamping force and creates a more secure attachment of the tub grip  100  to the bathtub wall.  
         [0027]     During the attachment process the clamp lever  208  is normally held in the horizontal position by a clamp spring  304 . The clamp spring  304  is positioned between the pressure plate  210  and a pin stop  216  and in a state of compression. This compression applies a force on the pressure plate  210 , which transfers that force to the cam  226  and urges the clamp lever  208  to remain in an horizontal position. The spring force is relatively mild and is easily overcome by the downward force applied to the end of the clamp lever  208 . The configuration of the clamp spring  304 , the pin stop  216 , the pressure plate  210 , the cam  226 , and the clamp lever  208  can be seen in  FIG. 7 .  
         [0028]     The first arm assembly pad  220  and a pivot pad assembly  110 , which is coupled to the second arm assembly  106 , can play a role in creating a secure attachment in the preferred embodiment. The first arm assembly pad  220  and the pivot pad assembly  110  are positioned to be in contact with opposite sides of the bathtub wall when the tub grip  100  is attached. Both have a friction pad that resists slippage when in contact with the tub wall. In addition, the pivot pad assembly  110 , which is comprised of a pivot pad  222  and a pivot pad pin  224 , is pivotally coupled to the second arm assembly  106 . This allows the second arm assembly  106  to maintain full contact with the tub wall, via the pivot pad  222 , while the clamp assembly  108  draws the second arm assembly  106  towards the first arm assembly  104  during the attachment process.  
         [0029]     In the preferred embodiment of the invention, the ratchet mechanism is comprised of a toothed locking member  202 , two locking plates  204 ,  206 , a locking plate spring  302  in contact with the first locking plate  204 , and a locking surface  702  in contact with the second locking plate  206 . The locking member  202  has a plurality of teeth configured as two series  802 ,  804  and located along the length of the upper and lower surfaces of the member  202 , respectively. The ratcheting behavior is enabled by the locking plates  204 ,  206 , which serve as pawls, engaging the two series of teeth  802 ,  804 . The locking plates  204 ,  206  apertures have flat upper and lower edge portions which can engage the upper and lower series of teeth  802 ,  804 . This engagement occurs when the locking plates  204 ,  206  are tilted until the upper and lower edge portions come into substantial contact with the upper and lower series of teeth  802 ,  804 . This configuration will restrict the movement of the plates  204 ,  206  along the length of the locking member  202  in one direction. When the locking plates  204 ,  206  are returned to an upright position, perpendicular to the length of the member, the upper and lower edge portions will disengage the teeth and allow the locking plates  204 ,  206  movement along both directions of the length of the locking member  202 .  
         [0030]     The preferred method for titling the locking plates  204 ,  206  is enabled by a locking plate spring  302  and a locking surface  702 , as shown in detail in  FIGS. 7 and 8 . The locking plate spring  302  is mounted on the locking member and placed in contact with the first locking plate  204 . The spring  302  is configured so that it is also in contact with a portion of the second arm assembly  106  and is maintained in a state of compression. The spring&#39;s  302  compression state urges the plates  204 ,  206  away from the spring  302 . A locking surface  702 , which serves as a mechanical stop, is positioned to be in contact with an upper portion the second locking plate  206 . The locking surface is a portion of the second arm assembly  106 . The combination of the spring force, applied at roughly the center of the first locking plate  204 , and an opposing force supplied by the locking surface  702  and applied near the upper extreme of the second locking plate  206 , cause the plates  204 ,  206  to tilt. The tilting, or rotation, will be about the line of contact between the locking surface  702  and the second locking plate  206 . This tilting behavior will result in the lower portions of the plates  204 ,  206  moving further away from the spring than the upper portions of the plates  204 ,  206  and in the lower portions of the plates  204 ,  206  locating closer the first arm assembly  104  than is the upper portions of the plates  204 ,  206 . The relationship of the locking plates  204 ,  206 , locking plate spring  302 , locking member  202 , and locking surface  702  result in a ratcheting behavior that allows the second arm assembly  106  to move towards the first arm assembly  104  and resists movement away from the first arm assembly  104 .  
         [0031]     The ratcheting behavior is further influenced by the geometry of the teeth. A tooth generally has two edge portions, a first edge portion  902  and a second edge portion  904 . The tooth and the edge portions can be distinguished by characteristic angles alpha, beta and gamma as shown in  FIGS. 8 and 9 . A characteristic angle for the tooth is the angle defined by the intersection of the first edge portion  902  and the second edge portion  904  at the peak of the tooth, labeled gamma in  FIG. 8  and  9 . The characteristic angles for the edge portions  902 ,  904  are the angle between a line defined by an edge potion  902 ,  904  and a center line  906  passing through the trough or valley between two teeth.  FIGS. 8 and 9  show the characteristic angle for the first edge portion  902  as alpha and the characteristic angle of the second edge portion  904  beta. The characteristic angles will determine how much resistance the locking plates  204 ,  206  provide as the ratchet is urged in the direction of allowable motion and how rigid the ratcheting mechanism is when urged in the direction that motion is restricted. In the preferred embodiment the teeth have characteristic angles of 100 degrees the first edge portions  902  have characteristic angles of 70 degrees and second edge portions  904  have characteristic angles of 30 degrees  
         [0032]     The invention is not limited to the use of plates with apertures mounted on a toothed locking member. There are a number of methods by which ratcheting behavior can be achieved, included, but not limited to, the use of one way gears or a spring loaded pin to engage a toothed locking member. In addition, ratcheting behavior can be achieved without the toothed locking member. One skilled in the art would immediately recognized that a variety material properties and geometries are capable of producing ratcheting behavior.  
         [0033]     In general, the process for removing the tub grip from the wall of a bathtub relies on disengaging the locking plates  204 ,  206  from the locking member  202 . This action is provided for by a locking plate release mechanism  602 , which is shown in  FIG. 6 . The release mechanism includes a locking plate release lever  218  and a locking plate release wire  214 . The release wire  214  is attached, on one end, to the release lever  218  and coupled, on the other end, to a pair of hooks  604 ,  606  extending from the bottom of the locking plates  204 ,  206 . When the lever  218  is actuated, by pulling it away from the locking plates  204 ,  206 , the release wire  214  exerts a force on the locking plates  204 ,  206  and moves the plates  204 ,  206  towards a vertical position. The plates  204 ,  206  pivot about a line of contact between the second locking plate  206  and the locking surface  702 . This results in the upper and lower edge portions of the aperture disengaging from the teeth of the locking member  202 . The force exerted on the plates  204 ,  206  by the release mechanism  602  must be large enough to overcome the force that the locking plate spring  302  exerts on the first locking plate  204 , which is urging the plates  204 ,  206  to remain in a tilted position. Once the upper and lower edge portions of the locking plate apertures are no longer in substantial contact with the teeth of the locking member  202 , the second arm assembly  106  can be manually moved away from the first arm assembly  104 . This releases the clamping force on the bathtub wall and allows the tub grip  100  to be removed.  
         [0034]     In the preferred embodiment, the locking plate release lever  218  is attached to the second arm assembly  106 . The release wire  214  passes through the second arm assembly  106  to couple to the locking plates  204 ,  206 . This configuration serves to apply a force that urges the second arm assembly  106  away from the first arm assembly  104  as the user pulls on the clamp lever  208  to disengage the locking plates  204 ,  206 . Once the second arm assembly  106  is moved away from the bathtub wall, the release lever  218  can be returned to its original position. This will cause the spring force from the locking plate spring  302  to return the locking plates  204 ,  206  to a tilted position, which reinstate the ratcheting behavior. Although the preferred embodiment references a release wire  204 , this component can be any connector that is capable of relaying force from one component to another while in a state of tension. The preferred embodiment also utilized hooks  604 ,  606  on the locking plates  202 ,  204  to which the connector  214  can couple. The invention is not limited to such coupling. One knowledgeable in the art would immediately see numerous methods of coupling, such as, but not limited to, coupling through a pin hole or other aperture or coupling through adhesives.  
         [0035]     The repeated attaching and detaching of the tub grip can cause wear and tear on some of the components, namely the locking member  202  and the locking plates  204 ,  206 . Both the teeth on the locking member  202  and the upper and lower portions of the aperture in the locking plates  204 ,  206  could lose effectiveness if too much wear accumulates. This potential issue can be addressed by constructing these components out of hardened materials, such as metals or very durable plastics. In the preferred embodiment of this invention, the materials used for the locking plates and the locking member is stainless steel.  
         [0036]     While the present invention has been illustrated by the description of embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention, in its broader aspects, is not limited to the specific details, the representative apparatus, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant&#39;s general inventive concept.