Abstract:
Handle is provided for battery operated razors. In some implementations, the handle includes a simple, efficient mechanism for both securing a battery cover to the handle of a razor and at the same time providing a high reliability electrical contact between the battery and electronics of the razor. The mechanism includes a closing system, including a first conductive component slidably attached within the battery cover and biased toward a predetermined axial position, and a second conductive component secured to the interior wall of the grip portion. The first conductive component is configured to interact with the second conductive component and move axially within the battery cover during engagement of the battery cover with the grip portion.

Description:
FIELD OF THE INVENTION 
     This invention relates to razors, and more particularly to razors for wet shaving that include a battery-powered functionality. 
     BACKGROUND OF THE INVENTION 
     In many small battery-operated devices, the batteries are replaceable by the user, and are inserted and removed from a battery compartment through an opening in a housing having a cover. It is necessary to mechanically secure the cover in place via a closing system so that the batteries do not fall out and the cover is not lost during use. Also, in the case of water-tight devices, the closure system provides a seal between the cover and the housing. It is also necessary to make electrical contact between the batteries and the electrical circuitry within the device, and to hold the batteries in place within the device. For many small battery-operated devices the closure system comprises a threaded connection. Since many small battery devices are made of plastic, the threaded connection is also plastic and can be somewhat fragile. As a result, the threaded closure system is subject to damage through repeated fastening and unfastening or if the connection is over torqued during tightening which a user may have a tendency to do since operation of the device is dependent on the connection. Therefore, there is a need for a closure system providing a mechanically secure connection on small battery-operated devices that signals the user when the closure system is adequately secure. 
     SUMMARY OF THE INVENTION 
     The present invention provides a simple, efficient mechanism for both securing a battery cover to the handle of a razor and at the same time providing a high reliability electrical contact between the battery and electronics of the razor. Preferred closing systems include very few parts and thus are easy and economical to manufacture and assemble. Moreover, some preferred closing systems are suitable for use with small, space saving handle designs and/or designs that includes seam lines between the battery cover and handle. 
     In one aspect, the invention features a battery operated razor comprising a housing including a grip portion (grip tube), a battery cover or shell and a closing system for fastening the battery cover to the grip tube. The grip tube is cylindrical and has an exterior wall defining a chamber having an interior wall and an open end. The battery cover is also cylindrical and has an exterior wall defining a cavity having an interior wall and an open end. The battery cover is removably mounted on the grip tube via the closing system and the grip tube chamber and battery cover cavity are configured to contain one or more batteries. The closing system comprises a first threaded portion at the grip tube chamber open end and a second threaded portion at the battery cover cavity open end mating with the first threaded portion. The closing system includes a first conductive component and a second conductive component. The first conductive component is slidably attached to the interior wall of the battery cover cavity and biased toward a predetermined axial position. The second conductive component is secured to the interior wall of the grip tube chamber; 
     The first conductive component comprises a contact surface facing and extending circumferentially about the battery cover cavity open end. The first conductive component contact surface comprises a first end and a second end opposite the first end and a kinked portion proximate the second end extending from the contact surface. 
     The second conductive component comprises a contact surface facing and extending circumferentially about the grip tube chamber open end. The second conductive component contact surface comprises a first end and a second end opposite the first end and a protrusion proximate the second end extending from the contact surface. As the first threaded portion at the grip tube chamber open end fastens to second threaded portion at the battery cover cavity open end during attachment of the battery cover to the grip tube, the first conductive component contact surface interfaces with the second conductive component contact surface such that the kinked portion of the first conductive component contact surface interferes with the second conductive component contact surface. The kinked portion slides circumferentially along the second conductive component contact surface deflecting the first conductive component axially. Once the kinked portion slides over the protuberance on the second conductive component contact surface an audible click is produced indicating that the attachment is complete. 
     In an alternate embodiment, the first conductive component comprises an L-shaped member extending circumferentially about the interior wall of the battery cover cavity proximate the battery cover open end providing a contact surface facing the open end. The first conductive component L-shaped member comprises a first end and a second end opposite the first end. The first end includes a vertical leg extending axially from the contact surface toward the open end of the cavity forming a first conductive component end stop and the second end includes a kinked portion proximate the second end extending axially away from the contact surface toward the battery cover open end. Similarly, the second conductive component comprises an L-shaped member extending circumferentially about the interior wall of the grip tube chamber and providing a contact surface facing the grip tube chamber open end. The L-shaped member comprises a first end and a second end opposite the first end. The first end includes a vertical leg extending axially from the contact surface away from the grip tube chamber open end forming a second conductive component end stop. The second end includes a protrusion proximate the second end extending from the contact surface, toward the grip tube chamber open end. 
     During attachment of the battery cover to the grip tube, the first conductive component contact surface interfaces with the second conductive component contact surface such that the kinked portion of the first conductive component contact surface interferes with the second conductive component contact surface. As the battery cover rotates relative to the grip tube, the kinked portion slides circumferentially along the second conductive component contact surface deflecting the first conductive component axially. Eventually the kinked portion slides over the protuberance on the second conductive component contact surface producing an audible click indicating that the attachment is complete. Either simultaneous with or shortly after the audible click, first conductive component end stop mates with the second conductive component end stop preventing further attachment of the cover to the grip tube. 
     In an alternate embodiment, the first conductive component comprises a first end, a second end and an elongate middle section therebetween, the elongate middle section is slidably attached to the interior wall of the battery cover. The first end comprises the L-shaped member previously described and the second end forms a U-shaped portion. The U-shaped portion has a first leg extending radially away from the elongate middle section to a bend and a second leg extending from the bend parallel to the first leg, back towards the elongate middle section. The second leg is attached to the interior surface of the battery cover allowing the first leg to deflect axially and to bias the first conductive component as it moves axially within the battery cover. The second leg includes a surface opposite the first leg providing a spring holder. The spring holder secures a spring for biasing the one or more batteries in grip tube chamber and battery cover cavity. 
     The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims. 
    
    
     
       DETAILED DESCRIPTION OF THE DRAWINGS 
         FIG. 1 a    is a top view of a razor handle according to one embodiment. 
         FIG. 1 b    is a bottom view of the razor handle of  FIG. 1   a.    
         FIG. 2 a    is a perspective view of the grip tube of the razor handle of  FIG. 1   a.    
         FIG. 2 b    is a perspective view of the battery cover of the razor handle of  FIG. 1   a.    
         FIG. 3  is a cross section view of the batter cover and the threaded connection between the battery cover and the grip tube. 
         FIG. 4 a    is a perspective view of the subassembly of the electrical components contained in the grip tube. 
         FIG. 4 b    is a perspective view of the second conductive component. 
         FIG. 4 c    is a perspective view of the printed circuit board (PCB) and PCB carrier. 
         FIG. 5  is a perspective view of the electrical components assembled in the razor handle (grip tube and battery cover). 
         FIGS. 6 a , 6 b , and 6 c    are different perspective views of the first conductive component removed from the battery cover. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Overall Razor Structure 
     Referring to  FIGS. 1 a  and 1 b   , a razor handle  10  includes a razor head  12 , a grip tube  14  (also referred to as a housing  14 ), and a battery shell  16  (also referred to as a battery cover  16 ). The razor head  12  includes a connecting structure for mounting a replaceable razor cartridge (not shown) on the handle  10 , as is well known in the razor art. The grip tube  14  is constructed to be held by a user during shaving, and to contain the components that provide the battery-powered functionality of the razor, e.g., a printed circuit board and a motor configured to cause vibration. The grip tube  14  is a sealed unit to which the head  12  is fixedly attached, allowing modular manufacturing and providing other advantages which will be discussed below. Referring to  FIGS. 2 a  and 2 b   , the battery cover  16  is removably attached to the grip tube  14 , so that the user may remove the battery cover  16  to replace the battery  38 . Battery cover  16  has a top region  19 . 
     As shown in  FIG. 3 , the battery cover  16  is removably attached to the grip tube  14  via a threaded connection  40 , allowing removal and replacement of the battery  38 . Once the battery cover  16  and the grip tube  14  are attached via the threaded connection  40 , electrical contact is established between the positive and negative terminals of the battery  38  and the electronic components of the razor through interaction of first and second conductive components  50 ,  80  assembled in the battery cover cavity  18  and grip tube chamber  11 , respectively. As shown in  FIG. 3 , the first conductive component  50  is assembled in the battery cover  16  and the second conductive component  80  is assembled in the grip tube  14 . Both are designed to interact as shown in  FIG. 3  as the battery cover  16  and the grip tube  14  are fastened together. The details of the first and second conductive components are fully discussed below. 
     The interface between the battery cover  16  and grip tube is sealed, e.g., by an O-ring, providing a water-tight assembly to protect the battery and electronics within the razor. The O-ring is generally mounted in groove  21  ( FIG. 3 ) on the grip tube, e.g., by an interference fit. Referring again to  FIG. 1 a   , the grip tube  14  includes an actuator button  22  that may be pressed by the user to actuate the battery-powered functionality of the razor via an electronic switch  29  shown in  FIG. 4   c.    
     Modular Grip Tube Structure 
     As discussed above, the grip tube  14  (shown in detail in  FIG. 2 a   ) is a modular assembly, to which the razor head  12  is fixedly attached. The modularity of the grip tube  14  advantageously allows a single type of grip tube to be manufactured for use with various different razor head styles. This in turn simplifies manufacturing of “families” of products with different heads but the same battery-powered functionality. The grip tube is water-tight except for the opening  25  at the end to which the battery cover  16  is attached, and is preferably a single, unitary part. Thus, the only seal that is required to ensure water-tightness of the razor handle  10  is the seal between the grip tube  14  and the battery cover  16  provided by the O-ring. This single-seal configuration minimizes the risk of water or moisture infiltrating the razor handle and damaging the electrical components. 
     The grip tube  14  contains a subassembly  26 , shown in  FIG. 4 a   , which includes a vibration motor  28 , a printed circuit board (PCB)  30  and a second conductive component  80 . The PCB  30  includes an electronic switch  29  and the positive contact  32  for providing battery power to the electronics. These components are assembled to a PCB carrier  34 , shown separately in  FIG. 4 c   , which is attached to the second conductive component  80  shown separately in  FIG. 4 b   . As shown in  FIGS. 4 a  and 4 b   , the second conductive component  80  comprises a first end  82 , a second end  86  and an elongate section  84  therebetween. The first end  82  includes an L-shaped member  88  comprising a contact surface  92  extending circumferentially, facing the open end  25  of the grip tube chamber  11 . The L-shaped member  88  includes a vertical leg  94  at a first end  90  extending axially from the contact surface  92 , toward the elongate section  84  forming a second conductive member end stop  94  and a protuberance  96  on the contact surface  92  near a second end  91  of the L-shaped member  88  opposite the first end  82 . The function of the protuberance  96  is described in the Battery Cover Attachment section below. The second conductive component second end  86  is attached to the PCB carrier  34  and is in electrical contact with the circuitry of the device. 
     During assembly of the subassembly  26  shown in  FIG. 4 a   , the positive contact  32  is assembled onto a PCB carrier  34  shown in  FIG. 4 c   , which is then mounted on the second conductive component second end  86  making electrical contact with the second conductive component  80 . Next, the printed circuit board  30  is placed in the PCB carrier  34  ( FIG. 4 c   ), and the vibration motor  28  is mounted on the PCB carrier  34  with lead wires being soldered onto the printed circuit board  30  to complete the subassembly  26 . The subassembly  26  may then be tested prior to assembly into the grip tube  14 . 
     The subassembly  26  is then installed into the grip tube chamber  11  so that it will be permanently retained therein. For example, the elongate section  84  of the second conductive component  80  may include protrusions or arms that engage corresponding recesses in the inner wall  13  of the grip tube  14  in an interference fit. In addition, the L-shaped member  88  of the second conductive component  80  is attached at the open end  25  of the grip tube  14  such that the second conductive component  80  contact surface  92  faces the opening  25  as shown in  FIG. 2 a   . For the embodiment shown in  FIG. 2 a   , the open end  25  of the grip tube  14  includes a lip  46  that extends beyond the threaded portion  42  of the grip tube  14  and penetrates into the battery cover cavity  18  and extends beyond the threaded portion  44  of the battery cover  16  during attachment of the cover  16  to the grip tube  14  as illustrated in  FIG. 3 . The second conductive component L-shaped member  88  is attached to the circumferential edge of the lip  46  so that the contact surface is oriented toward the opening  25  and the second conductive component end stop  94  on the L-shaped member is attached to the axial edge of the lip  46  as shown. 
     The grip tube  14  also includes an actuator button  22 . When the actuator button  22  is depressed, the underlying electronic switch  29  is contacted, which activates the circuitry of the PCB  30 . Activation may be by a “push and release” on/off action or other desired action, e.g., push on/push off. The electronic switch  29  makes an audible “click” when actuated, giving the user feedback that the device has been correctly turned on. The switch is preferably configured to require a relatively high actuation force applied over a small distance (e.g., at least 4 N applied over about a 0.25 mm displacement). This switch arrangement, combined with the recessed, low profile geometry of button  22 , tends to prevent the razor from being accidentally turned on during travel, or inadvertently turned off during shaving. Moreover, the structure of the switch/membrane/actuator member assembly provides the user with good tactile feedback. 
     Battery Cover Attachment 
     As discussed above, the battery cover  16  is removably attached to the grip tube  14  via the threaded connection  40  shown in  FIG. 3 , allowing removal and replacement of the battery  38 . For the embodiments shown in  FIGS. 2 a , 2 b   , and  3  the grip tube  14  includes the male threads  42  and the battery cover  16  includes the female threads  44 . However, in an alternate embodiment, the grip tube  14  can include the female threaded portion  44  and the battery cover  16  can include the male threaded portion  42 . Once the battery cover  16  and the grip tube  14  are attached via threaded connection  40 , electrical contact is established between the positive and negative terminals of the battery  38  and the electronic components of the razor handle  10  through interaction of the first and second conductive components  50 ,  80  assembled in the grip tube  14  and battery cover  16 , respectively. The details of the electrical components in the operating condition is shown in  FIG. 5 . 
     The grip tube  14  and the battery cover  16  are both made of plastic while the first and second conductive components  50 ,  80  respectively, are made of a conductive material such as metal. As shown in  FIG. 5 , the second conductive component second end  86  is attached to the PCB carrier  34  which is in electrical contact with the electric circuitry providing power to the motor  28 . The PCB carrier  34  includes positive contact  32  for the battery  38  providing electrical power to the electric circuitry. The negative terminal of the battery is in contact with a battery spring  78  which is connected to the first conductive component second end  56 . The electrical circuitry powering the motor  28  is completed by the first conductive component L-shaped member  58  at the first conductive component first end  52  contacting the second conductive component L-shaped member  88  at the second conductive component first end  82 . 
     The first conductive component  50  shown in  FIGS. 6 a  through 6 c    comprises a first end  52 , a second end  56  and an elongate section  54  therebetween. The elongate section  54  includes flange  55  slidably attached to the interior wall  17  of the battery cover  16 . The first end  52  comprises an L-shaped member  58  extending circumferentially about the interior wall  17  of the battery cover cavity  18  proximate the threaded portion  44  at the battery cover open end  35  providing a contact surface  62 . Preferably, the contact surface  62  is disposed at the end of the female threaded connection  44  on the interior  17  of the battery cover  16  facing the open end  35  and designed to make contact with the secondary conductive component  80  as the grip tube  14  male threaded portion  42  penetrates the battery cover open end  35  as shown in  FIG. 3 . The first conductive component L-shaped member  58  shown in  FIG. 6 a    comprises a first end  60  and a second end  61  opposite the first end  60 . The first end  60  includes a vertical leg  64  extending axially from the contact surface  62  toward the open end  35  of the cavity  18  forming a first conductive component end stop  64  and the second end  61  includes a kinked portion  66  proximate the second end  61  extending axially away from the contact surface  62  toward the battery cover open end  35 . 
     The second end  56  of the first conductive component  50  forms a spring element configured to apply an axial force between the grip tube and battery cover when the first and second conductive components are engaged. In the shown embodiment, the spring element is a U-shaped portion  70  shown in  FIG. 6 c   . The U-shaped portion  70  integrates a flexible area into the first conductive component  50 . The U-shaped portion  70  has a first leg  72  extending at an angle (preferably radially) away from the elongate section  54  to a bend  74  and a second leg  76  extending from the bend  74  parallel to the first leg  72 , back towards the elongate section  54 . The second leg  76  includes two spaced arms  780  which extend past the elongate middle section  54  with the elongate middle section  54  passing therebetween. The second leg  76  attached to the interior surface  17  of the battery cover  16  while the first leg  72  is unsupported. A space between the first leg  72  and the bottom of the battery cover cavity  18  enables the first leg  72  to produce a flexible area allowing it to deflect axially and to provide a spring loading effect as the first conductive component  50  slides axially along the interior wall  17  of the battery cover  16 . The second leg  76  includes a surface forming a platform opposite the first leg providing a spring holder  79 . The spring holder  79  secures the battery spring  78  for biasing the battery  38  in grip tube chamber  11 . 
     During attachment of the battery cover  16  to the grip tube  14  as shown in  FIG. 3 , the first conductive component contact surface  62  interfaces with the second conductive component contact surface  92 , particularly, the kinked portion  66  of the first conductive component contact surface  62  interferes with the second conductive component contact surface  92  as shown in  FIG. 3 . As shown in  FIG. 5 , the interaction establishes an electrical connection between the negative terminal of the battery  38  biased by the battery spring  78  and the positive end of the battery  38  in contact with the positive contact  32 . In addition, as the battery cover  16  rotates relative to the grip tube, the kinked portion  66  slides circumferentially along the second conductive component contact surface  92  deflecting the first conductive component  50  axially. Eventually the kinked portion  66  slides over the protuberance  96  on the second conductive component contact surface  92  producing a haptical click. This is perceived by the user as an audible click, providing a clear indication that the battery cover  16  has been correctly fastened. This click is the result of the action of the kinked portion  66  of the first conductive component L-shaped member  58  sliding quickly over the protrusion  96  on the second conductive component L-shaped member  88 . Either simultaneous with or shortly after the audible click, first conductive component end stop  64  mates with the second conductive component end stop  94  preventing further turning of the cover  16  on the grip tube  14 . The cross section depicted in  FIG. 3  shows the final closed position for the contact surfaces  62 ,  92 . As shown, the kinked portion  66  of the first conductive component L-shaped member  58  is in contact with the contact surface  92  of the second conductive component L-shaped member  88  contact surface  92  between the second end  91  and the protrusion  96  and the first conductive component end stop  64  contacts the second conductive component end stop  94  preventing further turning of the battery cover  16  on the grip tube  14 . This feature can inhibit damage to the parts due to over-tightening. 
     A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. 
     For example, while the razors described above include a vibration motor and provide a vibrating functionality, other types of battery-operated functionality may be provided, such as heating. 
     In some implementations, other types of battery shell attachment may be used. For example, the male and female threaded portions of the battery cover and grip tube may be reversed, so that the battery cover carries the male threaded portion and the grip tube carries the female threaded portion. 
     Some implementations include some of the features described above, but do not include some or all of the electronic components discussed herein. For example, in some cases the electronic switch may be replaced by a mechanical switch, and the printed circuit board may be omitted. 
     Accordingly, other embodiments are within the scope of the following claims. 
     The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm.” 
     Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern. 
     While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.