Abstract:
A handle mechanism for operating a vehicle door latch has a handle lever for operating the latching mechanism of a vehicle door latch and a button handle for operating the locking mechanism of the vehicle door latch. The handle mechanism includes a child security lock that disables the handle mechanism so that it cannot unlatch the vehicle door latch. The child security lock is engaged by the handle lever and disengaged by manipulating the handle lever and the button handle in a predetermined sequence.

Description:
TECHNICAL FIELD 
     A handle mechanism for operating a vehicle door latch has a handle lever for operating the latching mechanism of a vehicle door latch and a button handle for operating the locking mechanism of the vehicle door latch. The handle mechanism includes a child security lock that disables the handle mechanism so that it cannot unlatch the vehicle door latch. The child security lock is engaged by the handle lever and disengaged by manipulating the handle lever and the button handle in a predetermined sequence. 
     BACKGROUND OF THE INVENTION 
     Vehicle door latches typically include a latching mechanism for latching the vehicle door in the closed position and unlatching the vehicle door so that it can be pushed or pulled open. Vehicle door latches also typically include a locking mechanism that disables the latching mechanism after the door is latched in the closed position to prevent unauthorized or inadvertent unlatching and opening of the vehicle door. The latching mechanism typically includes separate links that are attached to respective inside and outside operators such as interior and exterior door handles for operating the latching mechanism. The locking mechanism typically includes separate links that are attached to respective inside and outside operators, such as an interior sill button and an exterior lock cylinder, for operating the locking mechanism. See, for instance, U.S. Pat. No. 5,277,461 granted to Thomas A. Dzurko et al Jan. 11, 1994 for a vehicle door latch of the type described above. 
     Vehicle door latches have included various ancillary features over the years. One of these features is a child security lock that is engaged to prevent operation of the latching mechanism by the interior door handle or other interior operator. The prior art vehicle door latches with child security locks typically include a decoupling member in the linkage system that connects the vehicle door latch to the interior door handle. The decoupling member is typically manually operated by an independent operator that is either hidden or inaccessible when the vehicle door is closed to prevent young passengers from disengaging the child security lock. However, such an inaccessible operator also prevents adult passengers from disengaging the child security lock and exiting the vehicle. See, for instance, U.S. Pat. No. 5,046,769 granted to Ronald P. Rimby and Rita M. Paulik Sep. 10, 1991 for a door latch coupling arrangement and U.S. Pat. No. 5,308,128 granted to Alfred L. Portelli and Rita M. Paulik May 3, 1994 for a vehicle door latch. 
     SUMMARY OF THE INVENTION 
     The object of this invention is to provide an operator for engaging or disengaging a child security lock that is readily accessible from the interior of the vehicle yet deters operation by young passengers. 
     A feature of the invention is that the operator for the child security lock of the vehicle door latch is part of an interior door handle mechanism for a vehicle door that includes a handle lever for operating the latching mechanism and a button handle for operating the locking mechanism of the vehicle door latch. 
     Another feature of the invention is that the handle mechanism includes a child security lock that is engaged easily but that requires two-handed operation for disengagement. 
     Another feature of the invention is that the handle mechanism includes a child security lock that is engaged easily but that requires a sequence of operations for disengagement so as to deter operation by young children. 
     Still another feature of the invention is that the handle mechanism includes a child security lock that is engaged and disengaged mechanically and thus operates independently of the vehicle electric power supply. 
     Yet another feature of the invention is that the handle mechanism has a child security lock that can be engaged or disengaged while the vehicle door is open or closed. 
     Still yet another feature of the invention is that the handle mechanism includes a handle lever that pivots in one direction to operate a door latch and an opposite direction to operate a child security lock and a unique spring arrangement for biasing the handle lever to a neutral or latch position between the two. 
     These and other objects, features and advantages of the invention will become more apparent from the following description of a preferred embodiment taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective rear view of a handle mechanism in accordance with the invention; 
     FIG. 2 is a front perspective view of the handle mechanism and FIG. 3 is a rear perspective view of the handle mechanism showing the parts in their respective positions when the handle mechanism is in a latched and unlocked condition with the child security lock disengaged; 
     FIG. 4 is a front perspective view showing the pats in their respective positions when the handle mechanism is in a latched and unlocked condition with the child security lock disengaged; 
     FIG. 5 is a rear perspective view showing the handle mechanism with the parts in an unlatched position when the handle mechanism is unlocked and the child security lock is disengaged; 
     FIG. 6 is a rear perspective view showing the handle mechanism with the parts in an unlatched position when the handle mechanism is locked and the child security is disengaged; 
     FIG. 7 is a front perspective view of the handle mechanism and FIG. 8 is a rear perspective view of the handle mechanism showing the parts in their respective positions when the child security lock is engaged with the locking lever in the locked position; 
     FIG. 9 is a rear perspective view of the handle mechanism showing the parts in their respective positions when the child security lock is engaged with the locking lever in the unlocked position; 
     FIG. 10 is a rear perspective view of the handle mechanism showing the parts in their respective positions when the handle lever is pivoted to the unlatch position; 
     FIG. 11 is a rear perspective view of the handle mechanism showing the parts in their respective positions when the locking lever is pivoted to the locked position while the handle lever is held in the unlatch position; 
     FIG. 12 is a rear perspective view of the handle mechanism showing the parts in their respective positions when the locking lever is pivoted back to the unlocked position while handle lever is held in the unlatch position; 
     FIG. 13 is a rear perspective view of the handle mechanism showing the parts in their respective positions when the locking lever is pivoted back to the lock position while handle lever is held in the unlatch position; and 
     FIG. 14 is a rear perspective view of the handle mechanism showing the parts in their respective positions when the handle lever is released and returns to the neutral or latched position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawing, FIG. 1 shows a handle mechanism of the invention indicated generally at  10 . Handle mechanism  10  comprises a housing  12  having a pair of integral, vertically spaced pivot gussets  14  and  16  and a cam projection  17  on the back side, a pivot pin  18  that extends through aligned holes in the pivot gussets and a handle lever  20  that is pivotally mounted on housing  12  by pivot pin  18 . Handle lever  20  has a generally flat body or handle  22  with upper and lower arms  24  and  26  protruding from the rear face of the body  22  at one end in perpendicular fashion. Handle  22  lies adjacent the front of housing  12  with upper and lower arms  24  and  26  protruding through respective slots of housing  12  to the back side where journal portions of arms  24  and  26  surround pivot pin  18 . 
     A coil spring  28  is disposed between the upper and lower arms  24  and  26  and surrounds pivot pin  18  loosely. Coil spring  28  has two tangential ends. End  30  engages abutment  32  of upper arm  24  and opposite end  34  engages abutment  36  of lower arm  26 . Spring ends  30  and  34  also engage housing  12  so that coil spring  28  holds handle lever  20  in a neutral position and returns handle lever  20  to the neutral position when handle lever  20  is pivoted clockwise or counterclockwise as explained below. Handle lever  20  is pivoted from the neutral position shown in FIG. 1 in a clockwise direction for an unlatching operation or in a counterclockwise direction to engage a child security lock which is also explained in detail below. 
     Handle mechanism  10  further comprises an unlatching lever  40  that pivots on the lower end of pivot pin  18  below the lower pivot gusset  16 . Unlatching lever  40  has an L-shaped slot  42  and an attachment hole  44  for attaching lever  40  to a door latch (not shown) by a control rod or other suitable linkage (not shown). Unlatching lever  40  is pivoted from the neutral position shown in FIG. 1 clockwise to an unlatching position via slot  42  to unlatch a conventional door latch in a well known manner as explained below. 
     Handle mechanism  10  further comprises a child security lever  46  that has a depending drive pin  48  at one end, a depending pivot pin  50  at the opposite end and an upwardly projecting pivot pin  52  midway between its ends. Drive pin  48  extends through a generally radial slot  54  in the lower arm  26  of handle lever  20  and projects into slot  42  of unlatching lever  40 . Pivot pin  50  pivots in a pivot hole  51  of lower arm  26 . Child security lever  46  is thus pivotally mounted on lower arm  26  for movement between a decoupled position and a drive position determined by the opposite ends of slot  54 . When child security lever  46  is in the drive position, drive pin  48  engages an inner end of radial slot  54  and a drive shoulder  56  in the narrow inner end of slot  42 . When child security lever  46  is in the decoupled or lost motion position, drive pin  48  engages an outer end of radial slot  54  and is located in the wide outer end of slot  42  where drive pin  48  bypasses drive shoulder  56  and moves in slot  42  without driving unlatching lever  40 . 
     Handle mechanism  10  includes an over center coil spring  58  that has one end attached to tab  53  of child security lever  46  and the other end attached to lower arm  26  and operates in a well-known manner so that drive pin  48  is biased against one or the other ends of the slot  54  of arm  26 . 
     A bypass lever  60  pivots on pivot pin  52  of child security lever  46 . A coil return spring  62  is on top of bypass lever  60  around pivot pin  52 . One end of spring  62  engages bypass lever  60  and the opposite end of spring  62  fits in a slot of pivot pin  52  so that bypass lever  60  is spring biased clockwise as viewed in FIG. 1 against an elevated stop  64  of child security lever  46 . 
     Handle mechanism  10  includes a locking lever  66  that pivots on a horizontal pivot  67  projecting from the backside of housing  12 . Locking lever  66  is shaped like a bell crank lever and has a button handle  68  at an end of one leg that projects through a window  70  of the housing  12  so that the locking lever  66  is operated from the front of housing  12 . Locking lever  66  has a flanged hole  69  midway in the other leg for attaching lever  66  to a door latch (not shown) by a control rod or other suitable linkage (not shown). Unlocking lever  66  is pivoted from the locked position shown in FIG. 1 clockwise to an unlocked position using button handle  68  to unlock the door latch (not shown) as explained below. 
     Locking lever  66  also controls a push rod  71  that has an end portion  72  that slides in a bracket  73  that is attached to the back side of housing  12 . The opposite end of push rod  71  is secured in an attachment hole  74  of locking lever  66  so that the end portion  72  of push rod  71  translates longitudinally in a generally horizontal direction when locking lever  66  is pivoted on horizontal pivot  67  that is generally perpendicular to the end portion  72 . End portion  72  thus translates between a locked position corresponding to the locked position of locking lever  66  and an unlocked position corresponding to the unlocked position of locking lever  66 . End portion  72  engages and pivots bypass lever  60  under certain conditions as explained below. 
     The Normal Unlatching Operation 
     Referring now to FIGS. 2,  3 ,  4  and  5 , the normal unlatching operation of handle mechanism  10  is as follows. FIG. 2 is a front perspective view of the handle mechanism  10  and FIG. 3 is a rear perspective view showing the handle mechanism  10  with the parts in a latched and unlocked condition with the child security lock disengaged. FIGS. 4 and 5 show the handle mechanism  10  with the parts in an unlatched and unlocked condition with the child security lock disengaged. 
     Handle mechanism  10  unlatches a conventional door latch (not shown) in well-known manner simply by pulling the end of handle  22  outwardly, which pivots the handle  22  of handle lever  20  outwardly from the flush neutral position (latched position) shown in FIG. 2 in a clockwise direction to the extended angular position (unlatched position) shown in FIG.  4 . This pivots upper and lower arms  24  and  26  of handle lever  20  from the latched position shown in FIG. 3 in a clockwise direction to the unlatched position shown in FIG.  5 . As upper arm  24  pivots, it moves spring end  30  away from housing  12  and tightens the coils of coil spring  28  in the clockwise direction. (This stores energy in coil spring  28  for returning handle lever  20  to the latched or neutral position shown in FIGS. 2 and 3 when handle  22  is released.) As lower arm  26  pivots, it drives unlatching lever  40  clockwise to the unlatching position via drive pin  48  of child security lever  46  which engages drive shoulder  56  of unlatching lever  40 . When unlatching lever  40  pivots clockwise to the unlatching position, the door latch (not shown) is unlatched by a control rod or other suitable linkage (not shown) secured to unlatching lever  40 . Handle  22  is then released and handle lever  20  is returned to the latched or neutral position shown in FIGS. 2 and 3 by coil spring  28 . 
     It should be noted that end portion  72  of push rod  71  engages bypass lever  60  pivoting bypass lever  60  counterclockwise on child security lever  46  as child security lever  46  moves clockwise with lower arm  26  during the unlatching operation. This feature allows drive pin  48  to remain in the inner end of slot  54  where drive pin  48  engages drive shoulder  56  of unlatching lever  40 . 
     Normal Unlatching Operation with Locked Handle Mechanism 
     FIG. 6 is a rear perspective view showing handle mechanism  10  with the parts in an unlatched position when the handle mechanism is locked and the child security lock is disengaged. Referring now to FIGS. 2,  3  and  6 , handle mechanism  10  is locked simply by moving button handle  68  down from the unlocked position shown in FIGS. 2 and 3 to the locked position shown in FIG.  6 . This rotates locking lever  66  counterclockwise from the unlocked position shown in FIG. 3 to the locked position shown in FIG.  6 . As locking lever  66  is pivoted to the locked position shown in FIG. 6, a control rod or other linkage (not shown) attached to flanged hole  69  is moved to lock a conventional door latch (not shown) in a well-known manner. As locking lever  66  is pivoted to the locked position shown in FIG. 6, locking lever  66  also withdraws end portion  72  of push rod  71 , translating push rod  71  to the right away from bypass lever  60 , i.e., from the position shown in FIG. 3 to the position shown in FIG.  6 . 
     The unlatching operation is still performed by pivoting handle  22  outwardly in a clockwise direction as described above and as shown in FIG.  4 . However, the unlatching operation is not effective at the door latch (not shown) because the door latch has been locked by locking lever  66 . It should be noted in connection with FIG. 6 that the bypass lever  60  is not effected in this case as handle lever  20  pivots clockwise from the latched position shown in FIGS. 2 and 3 to the unlatched position shown in FIG. 6 because portion  72  has been withdrawn by locking lever  66 . 
     Operation with Child Security Lock Engaged 
     The child security lock is engaged by pushing the end of handle  22  inwardly from the flush position shown in FIG. 2 to the child security lock engage position shown in FIG.  7 . This rotates handle lever  20  counterclockwise to the position shown in FIGS. 7 and 8. FIG. 7 is a front perspective view of handle mechanism  10  and FIG. 8 is a rear perspective view of handle mechanism  10  showing the parts in their respective positions when the child security lock is engaged and the locking lever  66  is in the locked position. 
     As lower arm  26  rotates counterclockwise to the child security position shown in FIG. 8, it moves spring end  34  away from housing  12  and tightens the coils of coil spring  28  in the counterclockwise direction. (This stores energy in coil spring  28  for returning handle lever  20  to the neutral or latched position shown in FIG. 2 when handle  22  is released). 
     As lower arm  26  rotates counterclockwise to the child security position shown in FIG. 8, cam  17  of housing  12  engages child security lever  46 , pivoting child security lever  46  counterclockwise about pivot pin  50  against the action of over center spring  58 . This shifts drive pin  48  to the outer end of slot  54  where drive pin  48  is now biased by the over center spring  58 . Drive pin  48  also shifts outwardly out of engagement with drive shoulder  56  and into the wider portion of slot  42  in unlatching lever  40 . 
     After the child security lock is engaged, handle  22  is released and the handle lever  20  is pivoted clockwise and returned to the neutral position where spring end  34  engages housing  12  (not shown). (The neutral position of arms  24  and  26  are about  10 ° clockwise from the position shown in FIG.  8 ). 
     The unlatching operation is now ineffective at the handle mechanism  10 . When handle lever  20  is pivoted clockwise from the neutral position to the unlatched position shown in FIGS. 4 and 5, the drive pin  48  simply moves in slot  42  without imparting any motion to unlatching lever  40 . Hence the door latch (not shown) that is connected to unlatching lever  40  by a control rod or other linkage (not shown) is not unlatched. 
     The child security lock can be engaged after an automotive door is closed, latched and locked as demonstrated above. However, the child security lock can also be engaged when the locking lever  66  is in the unlocked position shown in FIGS. 2 and 3 before or after the vehicle door is closed. The child security lock is still engaged by pushing the end of handle  22  inwardly to the child security lock position shown in FIG.  7  and the parts move to the same position except that the locking lever  66  and push rod are in the unlocked position as shown in FIG.  9 . Thus when handle  22  is released, bypass lever  60  engages the end portion  72  of rod  71  tangentially as child security lever  50  pivots clockwise about  100  with lower arm  26  to the latch position (not shown). Drive pin  48  is still shifted to and biased against the outer end of slot  54  by over center spring  58  and also shifted outwardly out of engagement with drive shoulder  56  and into the wider portion of slot  42  in unlatching lever  40  so that the unlatching operation is not effective after the child security lock is engaged. 
     Disengagement of the Child Security Lock 
     The child security lock is disengaged by simultaneous operation of handle lever  20  and locking lever  66  in a two-handed operation. Basically, handle lever  20  is moved to and held in the unlatching position with one hand while the locking lever  66  is cycled by the other hand. 
     The child security lock can be disengaged when the locking lever  66  is in the locked position shown in FIGS. 7 and 8 or in the unlocked position shown in FIG.  9  and after the handle lever returns to the latched or neutral position (not shown). 
     Referring first to FIGS. 10 through 14, the child security lock is disengaged when locking lever  66  is in the unlocked position as follows. First handle lever  20  is pivoted clockwise from the latched neutral position (not shown) to the unlatch position shown in FIG.  10 . As lower arm  26  pivots clockwise, drive pin  48  is held against the outer end of slot  54  by over center spring  58  and moves to the opposite outer end of the wide outer part of slot  42  in unlatching lever  40  as shown in FIG.  10 . Child security lever  46  thus pivots with lower arm  26  remaining stationary with respect to lower arm  26 . However, bypass lever  60  is held by the end portion  72  of rod  71  so that bypass lever  60  pivots counterclockwise on child security lever  46  away from stop  64  as child security lever  46  pivots clockwise to the position shown in FIG.  10 . 
     The handle lever  20  is held in the unlatching position shown in FIG. 10 while the locking lever  66  is pivoted clockwise to the locked position shown in FIG. 11 by pushing button handle  68  down. This withdraws rod  71 , i.e., moves rod  71  to the right as viewed in FIG.  10 . The withdrawing rod  71  releases bypass lever  60  which then pivots clockwise under the action of spring  62  into driving engagement with child security lever  46  and into the travel path of the end portion  72  of rod  71  as shown in FIG.  11 . 
     Locking lever  66  is then pivoted back to the unlocked position by pushing button handle  68  up while handle lever  20  is kept in the unlatching position. This projects rod end portion  72  forward, i.e., translates rod end portion  72  to the left from the position shown in FIG. 11 to the position shown in FIG.  12 . Rod end portion  72  engages bypass lever  60  driving bypass lever  60  to the left, which pivots child security lever  46  clockwise about pivot  50  which moves drive pin  48  from the outer end of slot  54  toward the inner end of slot  54  enough so that drive pin  48  is biased toward the inner end of slot  34  by over center spring  58 . Drive pin  48  is also moved radially inwardly toward the narrow inner portion of slot  42  and the drive shoulder  56  of unlatching lever  40 . 
     Locking lever  66  is then pivoted back to the locked position by pushing button handle  68  down while handle lever  20  is still held in the unlatching position as shown in FIG.  13 . This withdraws rod  71  to the right as viewed in FIG. 13, that is, away from bypass lever  60 . 
     After locking lever  66  is cycled from unlock to lock to unlock to lock, handle lever  20  is released so that coil spring  28  returns handle lever  20  to the neutral or latched position shown in FIG.  14 . As lower arm  26  of handle lever pivots counterclockwise from the unlatched position shown in FIG. 13 to the latched position shown in FIG. 14, drive pin  48  is biased inwardly against the inner end of slot  54  and into engagement with drive shoulder  56  in the narrow inner end of slot  42  by over center spring  58 . The handle mechanism  10  is now latched and locked with the child security lock disengaged. The door latch (not shown) operated by the handle mechanism  10  can now be unlocked by pivoting the button handle  68  up to the unlocked position shown in FIGS. 2 and 3 and then unlatched by pulling the end of handle  22  outwardly as shown in FIGS. 4 and 5. 
     The child security lock can also be disengaged when the locking lever  66  is in the locked position shown in FIGS. 7 and 8 and the handle lever  20  returns to the neutral or latched position (not shown). 
     Disengagement of the child security lock is still a two-handed operation. However, the first cycling step of the locking lever  66  is eliminated. The handle lever  20  is still pivoted outwardly and held in the unlatching position. However, the locking lever  66  need not be moved to the locked position shown in FIG. 11 because it is already in the locked position. Hence, the child security lock is disengaged by moving the handle lever  20  to the unlatched position shown in FIG.  11  and cycling the locking lever from the locked position of FIG. 11 to the unlocked position of FIG. 12 back to the locked position of FIG. 13 while the handle lever  20  is held in the unlatched position and then releasing the handle lever  20  so that it returns to the neutral or latched position shown in FIG.  14 . As indicated above, the handle mechanism  10  is now latched and locked with the child security lock disengaged. The door latch (not shown) operated by the handle mechanism  10  can now be unlocked by pivoting the button handle  68  up to the unlocked position shown in FIGS. 2 and 3 and then unlatched by pulling the end of handle  22  outwardly as shown in FIGS. 4 and 5. 
     Obviously, many modifications and variations of the present invention in light of the above teachings may be made. It is, therefore, to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.