Abstract:
A portable, mechanically operated, key-duplicating machine that relies on a punch-cutting system that selectively punches out the particular notches or “bittings” of a key blank in response to the details of an adjacent and aligned master key. The duplicating machine comprises a frame having cutting end and an alignment end. The frame defines a longitudinal axis. A carriage is movable along the longitudinal axis and includes a transverse axis. A key clamping assembly has a first key clamp for holding the key blank and a second key clamp for holding the master key. The key assembly is selectively slidable along the transverse axis. A cutting assembly is located at the cutting end and includes a punch-type cutter pin that is adapted to selectively cut pre-shaped notches from the held key blank. The cutter pin includes a guide section that aligns with the notch-profile of the held master key. The key clamping assembly is rotatable about the transverse axis and with respect to the carriage so that the mounted keys face either the cutting end or the alignment end of the frame.

Description:
BACKGROUND OF THE INVENTION 
   1) Field of the Invention 
   The present invention relates to a key-duplicating machine, and more particularly to an improved key-duplicating machine of the type that uses a punch-type cutter and requires no power supply. 
   2) Description of the Prior Art 
   There are two basic types of key cutting machines—duplicating key-cutting machines and code-cutting key-cutting machines. 
   A code cutting type machine includes a variety of cutting elements, each of which may be adjusted to control depth, relative position along the key blank, and angle of cut. The adjustment is digitized and follows a specific code, according to the manufacture of the key and lock, the type of lock, the type of key, and the specific shape of the key notches (the key combination). Code books are published listing the longitudinal spacing of the notches along the blade of the key blank and the depth increments of the notches for keys which are utilized to open substantially all types of locks. By following the specification in the code books, a locksmith can manually cut the proper notches in a key blank to duplicate a lost or misplaced key. 
   The standard equipment used by locksmiths is a duplicating machine which typically has a rotary filing or milling cutter for cutting key blanks. A key duplicating machine has three basic parts—a pair of vises coupled together and movable in unison, a key guide, and a cutter wheel. One vise holds the original or master key and the other vide holds a key blank. The key guide follows the profile of the original key and moves-the pair of vises together. As the key guide moves along the profile of the master key, the key blank moves correspondingly against the spinning cutter wheel so that the cutter wheel notches the key blank to the desired depth and shape as directed by the movements of the key guide. This arrangement is similar to machines called pantographs where a guide component is mechanically linked to a cutting assembly and thereby controls relative movement of the cutter, as desired. 
   Typical key duplicating machines operate on 110-volt AC or 12-volt DC current and are sometimes carried in a van or service truck, but are really not considered portable owing to their power requirements. 
   Such key-duplicating machines are useful for creating a key when an already cut key is available to be used as a guide. Where such a master (or any) key is unavailable, a code key-cutting machine can be used. 
   Both of these key-cutting systems have their benefits and disadvantages. The present invention is directed to improvements of the key-duplicating type key cutters. 
   Current duplicators rely on the controlled displacement of a rotating cutting wheel along a key-blank to cut the key blank according to the detail of an adjacent key-master which is used as a guide. Rotating the cutting wheel requires an electric motor and therefore requires a power supply, either batteries or a power cord, and an appropriate source of line voltage. This either makes the machine portable, but bulky and heavy, owing to the required batteries, or not portable in that line voltage is required. 
   There are several portable key-cutting machines disclosed in the prior art; however, these machines are of the code-cutting type and therefore require the specific code of the particular key to set the device prior to cutting the key blank. These devices are not able to cut a key blank using an already cut key as a guide (i.e., a key-duplicator key cutter). 
   Furthermore, regardless of the type of key-cutting machine used, each type and brand of key uses a specific bitting angle and therefore requires that the particular cutting element be capable of repeating that particular angle of cut. Some of the popular cutting angels include 72°, 78°, 84°, 86°, 87°, 90°, 100°, 104°, and 110° as measured from the cutting plane. This requires that the rotating cutting wheel be replaced prior to cutting the particular key. Replacement of this cutting wheel may require tools and time, which would likely make the key-duplicating process inefficient and inconvenient. 
   Other problems regarding portable code-type key-cutting machines include difficulty and awkwardness in operating the device which typically rely on pistol-style actuation and can require substantial strength to operate. 
   SUMMARY OF THE INVENTION 
   The invention provides a portable, mechanically operated, key-duplicating machine that relies on a punch-cutting system that selectively punches out the particular notches or “bittings” of a key blank in response to the details of an adjacent and aligned master key. The duplicating machine for cutting a key blank from the notch-profile of a master key comprises a frame having a cutting end and an alignment end. The frame defines a longitudinal axis. A carriage is included and is movable along the longitudinal axis and defines a transverse axis. A key clamping assembly has a first key clamp for holding the key blank and a second key clamp for holding the master key. The key clamping assembly is selectively slidable along the transverse axis. A cutter assembly is located at the cutting end and includes a punch-type cutter pin that is adapted to selectively cut pre-shaped notches from the held key blank. The cutter pin includes a guide section that aligns with the notch-profile of the held master key. The key clamping assembly is rotatable about the transverse axis and with respect to the carriage so that that mounted keys simultaneously face either the cutting end or the alignment end of the frame. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side elevation view of a key-duplicating machine according to a preferred embodiment of the invention, showing a plunger handle in an operative position; 
       FIG. 2  is a top plan view of the key-duplicating machine of  FIG. 1 , with the plunger handle in a cartridge-replacement position; 
       FIG. 3  is a rear elevation view of the key-duplicating machine of  FIG. 1 ; 
       FIG. 4  is a section view of the key-duplicating machine of  FIG. 1 , taken along the line  4 - 4  of  FIG. 2 ; 
       FIG. 5  is a section view of a portion of the key-duplicating machine of  FIG. 1 , taken along the line  5 - 5  of  FIG. 2  and showing detail of a slider block assembly; 
       FIG. 6  is a section view of a portion of the key-duplicating machine of  FIG. 1 , taken along the line  6 - 6  of  FIG. 5 , showing details of the slider block assembly; 
       FIG. 7  is a section view of a key clamp assembly taken along the line  7 - 7  of  FIG. 4 ; 
       FIG. 8  is a section view of a portion of the key-duplicating machine of  FIG. 1 , taken along the line  8 - 8  of  FIG. 4  and showing details of a broach-cutter assembly; 
       FIG. 9  is a side view of the key-duplicating machine of  FIG. 1 , showing the key-clamp assembly in an alignment and setup position and holding two keys against an alignment block; 
       FIG. 10  is a side view of the key-duplicating machine of  FIG. 1  showing the key-clamp assembly located in a cutting position; 
       FIG. 11  is a top plan view of a portion of the key-duplicating machine of  FIG. 1  taken along the line  11 - 11  of  FIG. 9  showing details of the key-clamp assembly located in the alignment and setup position; 
       FIG. 12  is a top plan view partially in section of a portion of the key-duplicating machine of  FIG. 1 , showing details of the key-clamp assembly located in a cutting position; 
       FIG. 12A  is an enlarged horizontal cross-section view of the cutter pin; and 
       FIG. 13  is a perspective view showing the relative positions of a key master and a key blank with respect to the cutter pin. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   This invention is a key-duplicating machine that is completely manual in operation and requires no power supply to operate. The machine is quick and easy to use, and can easily cut a key blank following the contours of an already cut key (a key master). 
   Referring to  FIG. 1 , a key-duplicating machine  10  is shown including a flat base plate  12 , a slider block  14 , a reference set-up block  16 , and cutting block assembly  18 . The slider block  14  is slidably mounted to base plate  12  between a set-up position and a cutting position, as described in greater detail below. 
   Referring to  FIGS. 2 ,  4 ,  5 ,  6 , and  11 , base plate  12  is generally rectangular in shape and includes two long sides  20 , two relatively shorter ends  22 , an upper surface  24 , and lower surface  26 . Base plate  12  further includes contact feet  28  which are secured to the lower surface  26  of base plate  12 , preferably at each corner. Collectively, feet  28  are used to raise the machine  10  above a surface making room for the components of the machine  10  to operate correctly, as described below, and to ensure that the machine  10  remains stable on a surface during use. 
   Base plate  12  includes two elongated slots  30  formed parallel to each other and parallel to long sides  20  of base plate  12 . The exact location, size and shape of slots  30  are not critical for the present invention to function properly. Slots  30  offer a preferred way to control the limits of movement of slider lock  14  with respect to base plate  12 , and to introduce a spring bias to the movement of slider block  14 , as described below. 
   Slider block  14  includes a horizontal sliding plate  32 , two vertical slide support plates  34 , and a transverse support pin  36 . Sliding plate  32  includes two side edges  38 , each of which are generally parallel to long sides  20  of base plate  12 , and secured to the side support plates  34  by appropriate fasteners such as machine bolts (not shown). 
   Each vertical slide support plate  34  defines an inside surface  39  and an outer surface  40 . A channel  42  (see  FIG. 6 ) is provided within inner surface  39  of each vertical side plate  34 . Each channel  42  is formed parallel to horizontal sliding plate  32  and is sized and shaped to receive both a respective side edge  38  of sliding plate  32  and a respective long side  20  of base plate  12 . 
   The arrangement is such that when sliding plate  32  is secured within the channels  42  of each vertical side plate  34 , the space provided within each channel  42  is sufficient to provide a snug-fit sliding engagement with each long side  20  of base plate  12 , as shown in section view in  FIG. 6 . To this end, the width of sliding plate  32  is equal to the width of base plate  12  so that side plates  34  secured to side edges  38  of sliding plate  32  slidingly engage the long sides  20  of base plate  12 . With this arrangement, slider block  14  can be slid along base plate  12 , as described below, while maintaining a high tolerance fit relative to the base plate  12  and cutting block assembly  18 , so that the cutting system will ensure high-tolerance cuts to keys blanks. 
   As shown in  FIGS. 5 and 6 , adjacent to each slot  30  of base plate  12 , a vertically disposed anchor pin  44  is secured to the lower surface  26  of base plate  12 . A vertically disposed spring pin  46  is secured to a lower surface  50  of sliding plate  32  of slider block  14  and positioned within each slot (two pins, as shown in  FIG. 6 ). Each spring pin  46  is sized and shaped to snugly slide within each respective slot  30  and help guide slider block  14  as it moves along the upper surface of base plate  12  and effectively controls the range of movement of slider block  14  (as defined by the length of the slots  30 ). 
   A spring  48  is attached between each spring pin  46  and its respective anchor pin  44  so that the two springs  48  remain parallel to each other and to long sides  20 . Springs  48  effectively introduce a spring bias to slider block  14  with respect to base plate  12  so that slider block is biased toward cutting block assembly  18 , as described below. 
   As shown in  FIGS. 1 ,  2 ,  9  and  10 , a key-movement handle  51  is provided, pivotally attached to a portion of base plate  12  at a pivot point  52  between a fully raised position, shown in  FIG. 9 , and a fully depressed position, shown in  FIG. 10 . Movement of key-movement handle  51  about pivot point  52  causes clamped keys (not yet discussed) to move within a horizontal plane which is parallel to the upper surface  24  of base plate  12 . 
   A link arm  54  is pivotally attached at a pivot point  56  to a portion of slider block  14  and also at another pivot point  58  to a portion of key-movement handle  51  so that angular displacement of key-movement handle  51  about pivot point  52  translates into linear movement of slider block  14  along base plate  12 . When slider block  14  moves linearly along the upper surface  24  of base plate  12 , its range of motion is limited by the length of slots  30  and, as mentioned above, block  14  is always biased towards the cutting block assembly  18  by springs  48 . 
   Transverse support pin  36  is supported in a bore  60  located within each vertical side support plate  34 . Support pin  36  is preferably slidably-fit into bores  60  so that pin  36  may freely slide within bores  60  with respect to side support plates  34 . 
   Fixed to support pin  36 , between side support plates  34 , is a key-clamping assembly  62  which is shown in  FIGS. 4 ,  6 ,  7 ,  11 , and  12 . Key-clamping assembly  62  is used to hold both a key master  64  and a key blank  66  in perfect alignment with respect to each other. Key clamping assembly  62  includes a clamp block  68 , which includes a bore  70  at one end that is sized and shaped to press-fit onto support pin  36 . Key master  64  and key blank  66  are both secured to an opposing clamp end  72  of clamp block  68 . Key clamping assembly  62  is generally rectangular and includes two opposing flat surfaces  74  at end  75 . Each flat surface  74  includes a first stepped surface  76  and a channel  78 . Located within each stepped surface  76  is a clamping plate  80 . Each clamping plate  80  is secured to within each respective stepped surface  76  by a bore  82  and a fastener  84 . As shown in  FIG. 4 , each fastener  84  includes an easy to operate knob  86  so that the clamping assembly may be operated by the operator without requiring tools. Appropriate springs  81  are used to bias each clamping plate  80  in an open position so that each respective channel  78  remains open and accessible for insertion of a key  64 ,  66 . 
   Each of the two channels  78  is formed along the outer edge  75  of clamp block  68  and is sized and shaped to receive a portion of either the master key  64  or the key blank  66  so that a portion of either respective key  64 ,  66  extends beyond its respective channel  78 . In this arrangement, a user can rotate knob  86  of each fastener  84  to tighten down each respective clamping plate onto the extended portion of each respective key located in its channel  78 . The purpose of clamp block  68  is to allow both master key  64  and key blank  66  to be held along a non-cutting edge of each key thereby exposing an edge of the key blank  66  to be cut, and the already cut edge detail of the master key  64 . 
   Clamp block  68  with keys  64 ,  66  in place in their respective channels  78  is pivotable about support pin  36  between a set up position (shown in  FIGS. 1 and 9 ), wherein keys  64 ,  66  are both directed towards the rear of the base plate  12  and reference set-up block  16 , and a cutting position (shown in  FIG. 10 ), wherein keys  64 ,  66  face the front of base plate  12  and cutting block assembly  18 . The swinging action of clamp block  68 , is shown in  FIG. 4 . 
   Referring to  FIGS. 1 ,  2 ,  4  and  11 , reference set-up block  16  includes an alignment post which has a vertical portion  90  and a base portion  92 . Base portion  92  of the alignment post includes a slot  94  which is parallel to the long side  20  of base plate  12 . Two alignment pins  96  are affixed within base plate  12  so that they extend above upper surface  24 . The pins are sized and shaped to fit snugly within slot  94  so that set-up block  16  may be selectively displaced between a rear position and a forward position. An appropriate fastener  100  is positioned within slot  94  and threaded within a threaded bore  102  located within base plate  12  so that set-up block  16  may be secured at a particular desired location between its range of movement, as shown in  FIG. 4 . 
   As shown in  FIGS. 1 ,  2  and  4 , cutting block assembly  18  is located at the front end of base plate  12  and includes an anchor block  104  which is affixed to upper surface  24  of base plate  12  using an appropriate fastener (not shown). An upper end  109  of anchor block  104  includes a handle-channel  106 . A plunger handle  108  is pivotally attached to anchor block  104  within handle-channel  106 . Anchor block  104  further includes a cartridge-receiving channel  110 , as shown in  FIG. 4 . Cartridge-receiving channel  110  is sized and shaped to snugly receive a cutting cartridge  112 , described in greater detail below. As shown in  FIG. 4 , cartridge  112  may be snugly positioned within channel  110  and secured into a cutting position against anchor block  104  using a bolt  114  that is positioned through a bore  116  of anchor block  104  and preferably includes a hand-operative knob  118 . In this arrangement, an operator may easily remove and secure any one of several cutting cartridges  112 , depending on the type and brand of key being cut, as described below. 
   Plunger handle  108  is pivotally attached to upper end  109  of anchor block  104 , as shown in  FIG. 4 , at pivot point  119  and is pivotal from a compressed position, generally shown in  FIG. 4 , wherein the cutter assembly has completed its cutting stroke, described below, and a fully open position, shown in  FIG. 2 , wherein plunger handle  108  is out of the way so that a user may easily remove cartridge  112 . Plunger handle  108  includes a handle portion  120  and a pivot support portion  122 . Pivot support portion  122  is preferably made from a strong rigid material and includes a contact surface  124 . 
   Referring to  FIGS. 1 ,  4 ,  8 , and  12 A, cutting cartridge  112  includes a block-frame  126  having an open channel  128  and an intersecting bore  130 . A cutter pin  132  is sized and shaped to slidingly fit within bore  130  between a resting position (shown in  FIG. 4 ) and a fully cut position. Cutter pin  132  includes a guide section  134  which is aligned with open channel  128  so that it is exposed and accessible to the user. Guide section  134  is generally triangular in section with the apex  135  of the triangle facing towards the rear of the base plate  12 . Cutter pin  132  further includes a cutting nib section  136  which is positioned just below the shaped guide section  134  so that the shape of the eventual cut matches the shape of the guide section  134 . Cutting nib section  136  includes an angled cutting edge  138 , shown in  FIG. 8 . A cutting support surface  140  is formed at the lower end of open channel  128  and is used to support the key blank during the cutting process, as described below in greater detail. Cutter pin  132  is designed to move a sufficient distance to ensure that cutting edge  138  extends equal to or preferably slightly below support surface  140 . 
   Cutter pin  132  is designed to be moved from a resting position to a depressed cutting position. To provide the required spring bias to keep cutter pin  132  in its resting raised position, shown in  FIG. 8 , a spring  142  is provided about an upper portion of cutter pin  132  and is located within a spring bore  144  (axially aligned with bore  130 ). Located adjacent spring  142  and affixed through cutter pin  132  is a spring pin  146 . Spring pin  146  passes generally perpendicularly to the longitudinal axis of cutter pin  138  and extends a prescribed distance beyond the cutter pin  132  on either side, as shown in  FIG. 8 . Spring  142  is a compression type spring and pushes against a lower section of spring bore  144  and against spring pin  146  in a known and understood manner to bias cutter pin  132  to a raised position, as shown in  FIG. 8 . Elongated cross-slots  148  are provided within block-frame  126  of cutting cartridge  112  on opposing sides of spring bore  144  to receive the extended portions of spring pin  146  and provide for its movement as cutter pin  132  moves its full range. Also, engagement of spring pin  146  with elongated cross slots  148  ensures that the entire cutter pin  132  remains aligned and moves in predictable manner during its entire range of movement. 
   As shown in  FIG. 8 , cutter pin  132  is supported in bore  130  at both sides of open channel  128  to ensure that cutter pin  132  remains aligned and supported, so that each cut made into the key blank is accurate and predictable. 
   Cutter pin  132  includes a contact portion  150  which extends beyond an upper section  152  of block-frame  128 . Contact portion  150  is designed to be contacted and depressed by contact surface  124  of plunger handle  108 . 
   Referring to  FIG. 13 , the relative cutting position of a held key blank  66  and a held and aligned key master  64  is shown with respect to cutter pin  132 . The figure shows how apex  135  of guide section  134  of cutter pin  132  fits snugly into each bitting or notch of key master and in doing so, automatically and correctly positions the held key blank  66 . When cutter pin  132  is depressed, as described below, cutting edge  138  engages key blank  66  and cuts a corresponding notch into key blank  66 . 
   Operation 
   In operation, a user first determines the type and size of key to be cut by referring to appropriate known charts. The user then selects an appropriate key blank  66  and an appropriate cutter cartridge  112 . Once selected, the cutter cartridge  112  is inserted and seated within channel  110  and held in position by tightening knob  118 . Once tightened within channel  110 , cutter cartridge  112  is automatically aligned and ready to cut keys. Handle  108  may be pivoted to its fully open position, as shown in  FIG. 2 , to provide more access to channel  110  during insertion of cutter cartridge  112 , if necessary. 
   Once the cutter cartridge is positioned within channel  110 , the user then positions the key-clamping assembly  62  so that it faces towards the key-reference block  16  (as shown in  FIG. 1 ) by pivoting the key-clamping assembly  62  and transverse support pin  36  within bores  60  of side support plates  34 . When the key-clamping assembly  62  is in this rearwardly facing position, the user mounts a key master  64  into the lower clamp of key-clamping assembly  62  (with its “teeth” facing away from the clamp) by positioning key  64  within channel  78  and rotating knob  86  and fastener  84  to tighten clamping plate  80  against key  64 , holding it within channel  78 . The user then places an appropriate key blank  66  in a similar manner into the upper key clamp with “teeth” portion (portion to be cut) facing away from the clamp. 
   To ensure that both keys are transversely aligned (with respect to the longitudinal axis of base plate  12 ), both key master  64  and key blank  66  are positioned so that their respective shoulders abut against a respective portion of clamp block  68 , as shown in  FIG. 12 . 
   The user has already adjusted reference set up block  16  to an appropriate position by loosening fastener  100  and sliding the base portion  92  along slot  94 . The appropriate position will depend on the type and size of key being cut, but for the most part, one location of the reference set-up block  16  will be appropriate for a majority of key types and sizes. 
   The user then pushes down on key-movement handle  51  so that slider block  14  is drawn rearwardly and so that the clamped keys  64 ,  66  are both advanced towards reference block  16 . The user lightly forces both held keys into contact with vertical portion  90  of reference block  16  to ensure that both held keys are aligned with respect to each other as they are held in their respective clamps of key-clamping assembly  62 . Key clamps may be adjusted if necessary and the keys moved until they both align longitudinally as well. 
   When both key master  64  and key blank  66  are correctly mounted within their respective lower and upper channels of clamp block  68 , the entire key-clamping assembly  62  (including fixed transverse support pin  36 ) is pivoted within bores  60  of slider block  14  so that the clamped keys  64 ,  66  face forward and lie adjacent to cutting block assembly  18 , as shown in  FIGS. 10 and 12 . Owing to the function of slider block  14  and springs  48 , it will be necessary for the user to simultaneously push down on key-movement handle  51  so that slider block  14  moves away from the cutter cartridge  112  as the clamp block  62  is pivoted from a rearwardly facing position to a forward-facing position. This is required so that the keys  64 ,  66  clear the cutting assembly and are allowed to settle in a proper cutting position with respect to cutter cartridge  122 , as shown in  FIGS. 10 and 12 . Once the clamped keys  64 ,  66  are facing and are adjacent to the cutter cartridge  112 , the user manipulates the key-movement handle  51  and the transverse support pin  36  to control the relative position of the keys with respect to the cutter pin  132 . The user moves the key master  64  along the guide section  134  until a particular notch of the key master  64  engages the guide section  134 . When this occurs, the user merely releases key-movement handle  51  so that springs  48  biases slider block  14  (and therefore key master  64 ) into tight engagement with guide section  134  of cutter pin  132 . When apex  135  of guide section  134  rests within the “valley” of the particular notch of key master  64 , the user may operate the cutter to cut a matching notch into the adjacent key blank  66 . 
   To operate the cutter, the user pushes down on plunger handle  108  so that the contact surface  124  presses directly down on contact portion of cutter pin  132 . As cutter pin  132  advances downwardly, angled cutting edge  138  forces the matching aligned portion of key blank  66  between it and the support surface  140 . This interaction is similar to a tool and die press. Eventually, sufficient force is applied to cut a notch in the relatively soft metal key blank  66 . Spring pin  146  ensures that cutter pin  132  returns to its home, rest position above the key master and key blank. Spring pin  146  preferably is strong enough to assist in lifting handle  108  as well. 
   Once the notch is cut, the user moves apex  135  of guide section  134  to the next notch detail of key master  64  and the process is repeated until the exact notch arrangement of key master is reproduced on the key blank  66 . 
   Once all notches of key master  64  are reproduced onto key blank  66 , the duplication process is complete and the keys are removed from clamp assembly by loosening knobs  86 .