Patent Publication Number: US-6988565-B2

Title: Retrofit kit for a modular control apparatus for a power impact tool

Description:
FIELD OF INVENTION 
   This invention relates generally to the field of power impact tools and, more particularly, to retrofitting a modular control apparatus to a power impact tool and more specifically to retrofitting timing devices to power impact tools. 
   BACKGROUND OF INVENTION 
   Power impact tools (e.g., pneumatic, hydraulic, electric, etc.) are well known in the art. Power impact tools produce forces on a workpiece by the repeated impact of a motor-driven hammer on an anvil that is mechanically connected, directly or indirectly, to exert a force on the workpiece. Some power impact tools exert linear forces. Other power impact tools exert torque, which is a twisting force. 
   One difficulty in current power impact tools is that power may be applied too long to the workpiece. The accumulation of impacts on any already tightened workpiece may cause damage. Current power impact tools shut off when the operator manually enables shutting off. For example, in a pneumatic hand tool such as a torque wrench, the operator releases the trigger valve to shut off the supply of compressed air to the tool motor. The number of impact forces delivered to the workpiece depends on the reflexes and attentiveness of the tool operator. During any delay, the workpiece may become overtorqued and damaged. 
   Applicant&#39;s co-pending application Ser. No. 10/213,702, discloses, among other things, a modular control apparatus. One modular control apparatus, a torque-timing device, is operative to limit the amount of time that torque will be applied after the operator initiates torque production from a power impact tool. For example, the operator may squeeze the trigger of a power impact torque wrench to initiate torque production. The modular torque-timing device is configured to be used with a particular family of power impact tools. It is desired to enable operators to use the modular torque-timing device with tools that were not originally manufactured to interface with a modular torque-timing device. Similarly, it is desirable to enable operators to use other modular control apparatuses with tools that were not originally manufactured to interface with a modular control apparatus. 
   Accordingly, there is a need in the field of power impact tools for an after-market product to provide more control of forces ultimately applied to a workpiece by a power impact tool. 
   SUMMARY OF INVENTION 
   The invention comprises retrofit kits for power impact tools. The retrofit kits adapt modular control apparatuses to power impact tools that where not originally manufactured to receive modular control apparatuses. The retrofit kits each comprise a modular control apparatus and at least one fastener. The modular control apparatus may be specially manufactured to adapt to retrofit tools or an adapter may be included in the kit. Adapters intercept the energy flow to the motor of the tool and re-channels the energy flow through a modular control apparatus, which then controls the flow of energy to the motor. Adapters also provide a mechanical interface between the tool and the modular control apparatus. The energy flow may be intercepted internally or externally to the tool. The retrofit kit may include instruction sheets describing and illustrating the methods of using the retrofit kit. 
   An first general aspect of the invention provides a kit comprising:
         a modular control apparatus; and   an adapter.       

   A second general aspect of the invention provides a kit comprising:
         a modular control apparatus; and   an adapter.       

   A third general aspect of the invention provides a kit comprising:
         an adapter..       

   A fourth general aspect of the invention provides a kit comprising:
         a modular control apparatus; and   an adapter, the adapter comprising a plurality of parts.       

   A fifth general aspect of the invention provides a kit comprising:
         an adapter, the adapter comprising a plurality of parts.       

   A sixth general aspect of the invention provides a kit comprising:
         at least one modular control apparatus;   an adapter, the adapter comprising at least one part; and   housing panels;       

   A sixth general aspect of the invention provides a kit comprising:
         at least one modular control apparatus;   an adapter, the adapter comprising at least one part;   housing panels; and   at least one fastener.       

   The foregoing and other features of the invention will be apparent from the following more particular description of various embodiments of the invention. 

   
     BRIEF DESCRIPTION OF DRAWINGS 
     Some of the embodiments of this invention will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein: 
       FIG. 1A  depicts a cross-sectional view of an embodiment of a power impact tool adapted to receive a modular, releasably-attachable control apparatus, in accordance with an embodiment of the present invention; 
       FIG. 1B  depicts a cross-sectional view of an embodiment of a modular, releasably-attachable, user-adjustable, control apparatus, in accordance with an embodiment of the present invention; 
       FIG. 2A  depicts a cross-sectional view of an embodiment of an adapter plate in accordance with an embodiment of the present invention; 
       FIG. 2B  depicts a cross-sectional view of an alternative embodiment of an adapter plate in accordance with an embodiment of the present invention; 
       FIG. 3A  depicts a plan view of an embodiment of a backplate of a retrofit tool; 
       FIG. 3B  depicts the adapter of  FIG. 2B  aligned to  FIG. 3A ; 
       FIG. 3C  depicts an interface surface of a modular control apparatus aligned to  FIG. 3B ; 
       FIG. 4  depicts an example of an embodiment of a modular control apparatus connected to an adapter which intercepts an energy flow between a handle and a motor of a tool; 
       FIG. 5  shows an example of an embodiment of a modular control apparatus specially adapted to intercept the flow of energy outside of the tool; and 
       FIG. 6  shows an example of an embodiment of a modular control apparatus connected to an adapter specially adapted to intercept the flow of energy outside of the tool. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Although certain embodiments of the present invention will be shown and described in detail, it should be understood that various changes and modifications may be made without departing from the scope of the appended claims. The scope of the present invention will in no way be limited to the number of constituting components, the materials thereof, the shapes thereof, the relative arrangement thereof, etc., and are disclosed simply as an example of an embodiment. Although the drawings are intended to illustrate the present invention, the drawings are not necessarily drawn to scale. 
   A particular modular control apparatus is used with, or as part of, a power impact tool and, in particular embodiments, allows for time-limiting the torque output. Power impact tools can include various power (e.g., pneumatic, hydraulic, electric, etc.) impact tools. The exemplary my modular control apparatus shown herein; represents a modular control apparatus including a torque limiting timing device  17  (as shown in  FIG. 1B ) that when used with a power impact tool, for example with a pneumatic impact tool, provides a fixed duration of torque from the air motor within the tool, to a workpiece, such as a nut or bolt. 
   A motor, as defined and used herein, is any device for converting a first energy into kinetic energy. For example, an air motor converts the energy of an expanding compressed gas into the rotational motion of a mechanical drive shaft. For another example, an electric motor converts electricity into the rotational motion of a mechanical drive shaft. For yet another example, the drive piston and valves of a jack hammer form a motor to convert the energy of an expanding compressed fluid into linear motion of a mechanical drive shaft. For a final example, a hydraulic motor converts the kinetic energy of a flowing, slightly compressible fluid (hydraulic fluid) into the rotational motion of a mechanical drive shaft. The drive shaft, in each embodiment, is rotated by the motor, and tools, for operating on work pieces (workpiece adapters) are mechanically connected directly or indirectly between the drive shaft and the work piece. 
   Referring now to  FIG. 1A , an embodiment of a power impact tool  10  is shown in a vertical section through the centerline of the tool  10 . The tool  10  has a handle  12  containing a channel  50  for receiving a compressible fluid through a port  52  at the base of the handle  12 . A channel comprises a confined path for the flow of a compressible fluid. Channels may be pipes, hoses, bores formed in a block of material, or similar flow constraints. Channels may include couplings. In some particular embodiments, channels may include a valve. The tool  10  also has a housing  16  which covers the motor  14  and other moving parts to protect the operator. The housing  16  conventionally comprises a plurality of housing sections or panels. 
   A compressible fluid, as defined and used herein, is a fluid with a bulk modulus that is less than the bulk modulus of water. Compressible fluids with low bulk moduli transfer energy by converting the potential energy of their compressed state into the kinetic energy of an expanding fluid and then into the kinetic energy of a motor rotor. Elemental gases, such as helium and nitrogen, and mixed gases such as air, are compressible fluids with low bulk moduli. Slightly compressible fluids have high bulk moduli and are used for force transmission. Hydraulic fluids, for example, typically have higher bulk moduli. Either type of compressible fluid can transfer energy into a motor. 
   The port  52  is equipped with a fitting  54  for connecting to a supply of compressed fluid. A supply of compressible fluid may be, for example, a hose supplying compressed air such as is used in an auto repair shop to power pneumatic tools. Within the channel  50  is a manually operated valve  62 , shown in  FIG. 1A  as a trigger valve  62 , which enables the tool-user to initiate the flow of compressible fluid through the channel  50 . By depressing the trigger  60 , the valve  62  is opened, thereby channeling the compressible fluid toward a motor  14  of the tool  10 . To reach the motor  14 , the compressible fluid must be channeled from port  56  to port  58 . This may be accomplished by attaching the modular control apparatus  600  or by attaching an end cap of the housing (not shown) which connects port  56  to port  58 . The channel  50  extends to a backplate  70  of the tool where the channel  50  terminates at a port  56  sized and shaped to receive (see  FIG. 1B ) a corresponding port  250  to a first channel  202  in an exemplary modular control apparatus  600 . Thus, the first channel  202  is the input channel to the modular control apparatus  600 . 
   A modular control apparatus  600  is a first apparatus that controls at least one function of at least one second apparatus. A modular control apparatus  600  is modular in that it may be manipulated as a single physical unit (a module). The module comprises a generally solid block, or body, within which are formed the mechanisms which implement control functions. The body may be created from a single block or may be built up from a plurality of sub-blocks. The modular control apparatus  600  may be manipulated into a relationship with a second apparatus in which interaction between the modular control apparatus  600  and a second apparatus results in a change in the operation of the second apparatus. For some examples in the field of pneumatics, a modular control apparatus  600  may shut off air flow to a tool  10  (a second apparatus) after a user-selected time, may oscillate the direction of air flow, as in a jack hammer, or may change the pressure of the air entering the second apparatus. 
   The exemplary modular control apparatus  600  is configured to be releasably attachable to the tool  10 . The apparatus is releasably attachable when the connections between the modular control apparatus  600  and the tool  10  can be opened and closed by the tool user. The connectors may be bolts, clamps, latches, locks, or similar devices known in the art. In an embodiment, the connections can all be opened or all be closed by a single motion of the user&#39;s hand. For example, a lever-activated connector may be opened by operation of the lever. 
   Located on the backplate  70  is a port  58  sized and shaped to receive the compressed fluid which is discharged from an output port  252  (  FIG. 1B ) of a second channel  212  of the modular control apparatus  600 . The second channel is the output channel. The backplate  70  may be, for example, the backplate  70  of a Model 749 pneumatic torque wrench made by Chicago Pneumatic Tool. In an embodiment, the backplate  70  has a cylindrical protrusion  74 , perhaps accommodating a motor bearing within, which is used as an alignment mechanism for aligning the modular control apparatus  600  to the tool  10 . 
   For a retrofit tool  11  ( FIG. 4 ) which is not designed to receive a modular control apparatus, the backplate  70  may receive an adapter  500  or  700  ( FIGS. 2A and 2B ) which provides an interface between the retrofit tool  11  and the modular control apparatus  600 . Refer now to  FIGS. 2A and 2B . In such retrofit cases, adapters  500  and  700  may be designed for each uniquely designed retrofit tool  11 . On the modular control apparatus-receiving side of the adapters  500  and  700  (the right-hand side in  FIGS. 2A and 2B ), at least a portion of the adapter may be configured like the backplate  70  of a tool  10  ( FIG. 1 ) for which the modular control apparatus  600  was originally designed. On the retrofit-tool-receiving side (the lefthand side in  FIGS. 2A and 2B ), the at least a portion of the adapter  500  or  700  may be configured like a backplate  504  of the retrofit tool  11 . Remaining portions of the adapter  500  provide two channels for compressible fluids: a first adapter channel  510  between the compressible fluid supply  516  and the adapter output port  56  which couples with the input port  250  of the modular control apparatus  600 . A second adapter channel  508  receives compressible fluid from the discharge port  252  of the modular control apparatus  600  through coupled port  58  and channels the compressible fluid to the retrofit tool  11  and there through to its motor  14  ( FIG. 4 ). The adapter  500  and  700  also provides sufficient structure  70  and  790  and attachment mechanisms for securing the adapter  500  or  700  to the retrofit tool  11  and to the modular control apparatus  600 . 
   Referring again to  FIGS. 1A and 1B , the alignment mechanisms  72 ,  74 ,  76 , and  78  comprise passive means to ensure that the input port  250  and discharge port  252  of the modular control apparatus  600  mate sealingly with the fluid supply port  56  and the motor inlet port  58  of the tool  10 , respectively. In an embodiment, the backplate  70  of the tool  10  has a cylindrical extension  74  that fits into a corresponding recess  78  in the modular control apparatus  600 . The backplate  70  is further equipped with at least one asymmetrically arranged rod  72  corresponding to at least one hole  76  in the modular control apparatus  600 . The rods  72  are arranged asymmetrically so that there is only one orientation of the modular control apparatus  600  that will allow the apparatus  600  to be received onto the tool  10 . That orientation is the orientation at which the ports of the apparatus  250  and  252  and the tool will line up properly. The attachment mechanism may be as simple as a bolt through the modular control apparatus into a threaded hole in the tool. Those skilled in the art of tool manufacture will be aware of many different ways of making the attachment. The requirements for the attachment mechanism are that it create a seal against leakage of the compressible fluid and that it be reusable. 
   It is desirable to adapt the modular control apparatus  600  to tools  11  ( FIG. 4 ) that were not originally designed to receive it. There are two basic approaches to accomplishing this. In some embodiments, a modular control apparatus  600  that is unique to each retrofit tool  11  may be designed. This approach loses economies of scale in the production of the modular control apparatus  600 . In other embodiments, adapter kits may be provided. Adapter kits provide means to adapt a modular control apparatus to a tool not originally manufactured to receive the modular control apparatus  600 , which will be referred to as a “retrofit tool”  11  ( FIG. 4 ). Consider three approaches to adapting a modular control apparatus  600  to a retrofit tool  11 . 
   A retrofit kit may comprise a modular control apparatus  600  uniquely designed for the retrofit tool  11  and fasteners. A retrofit kit is formed when all of its parts are delivered to a common destination. 
   First, in cases where a backplate  310  ( FIG. 3A ) of a retrofit tool  11  provides access to the compressible fluid supply to the motor, an adapter may be made to interface with the modular control apparatus  600  to attach the modular control apparatus  600  behind the motor  14  ( FIG. 1A ) to a backplate of the retrofit tool  11 . Referring to  FIG. 2A , an adapter  500  comprising at least a portion of a backplate  504  of a retrofit tool  11  may be formed by mechanically connecting a backplate  70 , designed to receive the modular control apparatus  600  ( FIG. 1B ), with a backplate  504  of a retrofit tool  11 . The mechanical connection may be by means of girders  501  connected by bolts  502 . In other embodiments, the mechanical connection may be by plates, shells, bolts, or any other means of maintaining a substantially rigid connection between the back plates  70  and  504 . Channel  510  connects the compressible fluid supply port  56  of back plate  70  with the supply port  516  of backplate  504 . Channel  508  connects motor inlet port  58  of backplate  70  with motor inlet port  512  of backplate  504 . Backplate  504  may have alignment recesses  514  and  506  as well as attachment mechanisms (not shown) for attaching to the retrofit tool  11  for which it is designed. 
   Referring to  FIG. 2B , in an embodiment, the adapter may be formed as at least one piece  700  with the tool-receiving features  506 – 516  of a retrofit tool&#39;s  11  backplate  310  ( FIG. 3A ) and features  56 ,  58 ,  72 , and  74  for receiving the modular control apparatus  600 . 
   A retrofit kit for an embodiment of  FIGS. 2A–B  comprises an adapter  500  or  700 , a modular control apparatus  600 , and fasteners and couplings (not shown) adapted to the specific designs. 
   Referring to  FIG. 3A-C , the plan view of the backplate  310  ( FIG. 3A ) of a retrofit tool  11  comprises a compressible fluid supply port  314  which couples with adapter  700  ( FIG. 3B ) port  516  to channel compressible fluid through adapter port  56  to compressible fluid inlet port  250  of the modular control apparatus  600  ( FIG. 3C ). Backplate  310  further comprises a motor inlet port  318 , which receives compressible fluid from adapter port  512  that has been channeled through adapter port  58  from the discharge port  252  of the modular control apparatus  600 . Backplate  310  further comprises alignment features  312  and  316 , which fit in only one orientation with alignment features  506  and  514  on adapter  700 . Likewise, alignment features  72  and  74  of adapter  700  fit in only one orientation with alignment features  76  and  78  of modular control apparatus  600 . 
   A retrofit kit for an embodiment of  FIGS. 3A–C  comprises an adapter  700 , a modular control apparatus  600 , and fasteners and couplings (not shown). In a particular embodiment, the retrofit kit may include at least one instruction sheet describing and illustrating the methods of using the retrofit kit. In other particular embodiments, the adapter  700  may be fixedly attached to the modular control apparatus  600 , wherein the combined adapter  700  and modular control apparatus  600  are releasably attached as a unit to the retrofit tool  11 . 
   Refer to  FIG. 4 . A second approach to adapting a modular control apparatus  600  to a retrofit tool  11  involves inserting an adapter  900  between the top of the handle  12  and the motor  14 . A modular control apparatus  600  for a pneumatic power impact retrofit tool  11  must have access to the compressed air supply line  50  to the air motor  14 , in order to re-channel the compressed air through the modular control apparatus  600 . For some retrofit tools  11 , the compressed air supply line  50  may be intercepted between the handle  12  and the air motor  14 . Pneumatic tools are conventionally constructed by attaching an air motor  14  to a handle  12  with an air supply valve  60  ( FIG. 1 ) and adding a housing  16 . For such retrofit tools  11 , a portion of an adapter  900  may be fit between the air motor  14  and the handle  12 . If the trigger valve  62  is modular, it may have a coupling that can be exploited. Likewise, any coupling on the motor  14  inlet should be exploited by adapter  900 . Adapter  900  receives the compressible fluid flow from handle channel  50  into adapter channel  910 , which channels the compressible fluid flow into modular control apparatus  600  inlet port  250 . The modular control apparatus  600  channels its output compressible fluid through port  252  and into adapter channel  908 . Adapter channel  908  conducts the compressible fluid to the motor  14 . Fastener  950  helps to secure the modular control apparatus  600  to the retrofit tool. Depending on the configuration of retrofit tool  11 , the adapter kit may need to include a new housing  16  or sections thereof sections to replace the original one, which may no longer fit after an adapter  900  is inserted between the handle  12  and the air motor  14 . 
   A retrofit kit for an embodiment intercepting the compressible fluid flow between the handle  12  and the motor  14  may comprise a modular control apparatus  600 , an adapter configured to fit between the handle  12  and the motor  14  and to conduct compressible fluid to and from the modular control apparatus  600 , and fasteners and couplings. 
   Refer to  FIG. 5 . A third approach to adapting a modular control apparatus  610  to a retrofit tool  11  involves intercepting the compressible fluid supply before it ever enters the retrofit tool  11 . Adapted modular control apparatus  610  may be a modified version of modular control apparatus  600 , wherein the modifications adapt the modular control apparatus to the tool without a separate adapter. The adapted modular control apparatus  610  may be releasably attached to the base of the handle  12 . In an alternate embodiment, adapted modular control apparatus  610  may be attached behind the motor  14 . In a particular embodiment, the compressible fluid supply hose  440  that normally connects at coupling  54  ( FIG. 1 ) may be connected to port  250  with a coupling, and port  252  may be connected to coupling  54  ( FIG. 1 ) with a hose and a coupling. In such retrofit cases, a trigger valve  420  may be needed between the air supply hose  440  and the adapted modular control apparatus  610 . Thus, a particular embodiment of a retrofit kit for a retrofit tool  11  comprises an adapted modular control apparatus  610  with a trigger valve  420  upstream of port  250 , a modified trigger mechanism  430 , attachment hardware  450 , a hose  410  or similar channel for connecting compressible fluid from the trigger valve  420  to port  250  of the modular control apparatus  610 , and a seal or coupling connecting port  252  to port  52 . In such an embodiment, trigger valve  60  ( FIG. 1 ) would be locked open or removed to allow the retrofit trigger valve  420  to control operation of the retrofit tool  11 . 
   A retrofit kit for the embodiment of  FIG. 4  may comprise a adapted modular control apparatus  610 , trigger valve  420 , trigger  430 , channels  440  and  410 , fasteners  450 , and couplings (not shown). 
   Refer to  FIG. 6 . In some embodiments, an adapter  800  is placed between the base of the handle  12  and the modular control apparatus  600 . The adapter  800  may, in addition to making the necessary fluidic connections, position the modular control apparatus  600  to provide a retrofit tool  11  with a desirable balance and grip. Compressible fluid supply line  440  enters adapter  800  at any convenient point and runs to the trigger valve  420 . The compressible fluid supply line  440  may be disposed inside or outside of the handle  12 . Trigger valve  420  is actuated to open by squeezing trigger  430 . When trigger valve  420  is open, compressible fluid flows through channel  410 , through the adapter, and into the inlet port  250  of the modular control apparatus  600 . Compressible fluid leaving the modular control apparatus  600  through port  252  is channeled through the adapter to port  52  in the handle  12  of the retrofit tool  11 . The compressible fluid then moves through channel  50  to motor  14 . 
   In a particular embodiment, the original valve  60  ( FIG. 1 ) is used, and the flow is intercepted just downstream of the valve, channeled through the handle  12  and an adapter  800  to the inlet port  250  of the modular control apparatus  600 , and returned from port  252  in the modular control apparatus  600  to the motor  14  via the adapter and a new channel  410  in the handle  12 . Those of skill in the art will recognize that, once a choice has been made to intercept the supply of compressible fluid before it reaches the retrofit tool  11 , the modular control apparatus  600  may be attached to any point on the tool  11  that does not interfere with operating the tool  11 . 
   In a particular embodiment, the adapter  800  may be configured to provide access to the manual control element  599  on the modular control apparatus  600  to a hand which is gripping the tool  11 . For example, in  FIG. 6 , if the modular control apparatus  600  was reoriented so that manual control element was just below the trigger valve  420 , the operator may manipulate the manual control element  599  with one finger of the hand gripping the tool  11 . 
   A retrofit kit for an embodiment shown in  FIG. 6  may include a modular control apparatus  600 , an adapter  800 , channels  410  and  440  for compressible fluid flow, a trigger valve  420 , a trigger  430 , and couplings and fasteners (not shown). 
   While this invention has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the embodiments of the invention as set forth above are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention as defined in the following claims.