Abstract:
A rivet setting tool is provided with a mandrel collection system. The mandrel collection system uses a valve system to provide high and low vacuum states to draw rivet mandrels into a collection bottle. The low vacuum state provides an energy savings and reduced noise levels.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit of U.S. Provisional Application No. 60/428,116, filed on Nov. 21, 2002. The disclosure of the above application is incorporated herein by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates generally to rivet setting tools, and more particularly to a mandrel collection system for a rivet setting tool.  
         BACKGROUND OF THE INVENTION  
         [0003]    Various types of rivet setting tools are known in the industry. Some include spring actuated, pneumatically actuated, hydraulically actuated systems and combinations thereof. As rivet setting tools have developed, manufacturers strive to improve the efficiency, reduce the complexity and increase an operator&#39;s ease in handling the tool.  
           [0004]    Rivet setting tools using pneumatic actuation to withdraw a spent mandrel from the rivet setting tool into a collection system typically apply a constant vacuum or air pressure to the rivet setting tool. Often the mechanism to create a vacuum can utilize a constant stream of compressed air. Unfortunately, the vacuum is really only needed immediately after the rivet is being set. The constant flow of highly compressed air is therefore an inefficient from an energy standpoint as well as a source of a significant amount of unnecessary noise.  
           [0005]    It is therefore desirable in the industry to provide a rivet setting tool having a mandrel collection system that can vary the amount of mandrel collection vacuum depending upon the time within a duty cycle. Additionally, it would be desirable to provide which can be quickly adapted for varying sizes of rivets and easily disassembled for cleaning and general maintenance. It is an object of the present invention to provide a rivet setting tool, which overcomes the deficiencies in the prior art.  
         SUMMARY OF THE INVENTION  
         [0006]    In one embodiment of the invention, a hand held tool for setting a rivet having a rivet having a removable mandrel is disclosed. A mandrel collection system coupled to the rivet setting tool is provided, which is configured to provide first and second vacuum levels, with the second vacuum level being sufficient to draw the mandrel from the rivet setting tool into the mandrel collection system. The first vacuum level is less than the second vacuum level.  
           [0007]    In another embodiment of the invention, an apparatus for setting a fastener having a mandrel is disclosed. The apparatus has an air supply module; a vacuum control module coupled to the air supply module; and a collection bottle defining a generally sealed collection cavity. The vacuum control module is configured to provide first and second vacuum levels within the generally sealed cavity, said second vacuum level being sufficient to draw the mandrel into the sealed cavity.  
           [0008]    In another embodiment of the invention, an apparatus for moving a portion of a fastener from one location to another is disclosed. The apparatus has a vacuum control module and a member defining a generally sealed cavity. The vacuum control module is configured to provide first and second vacuum levels within the sealed cavity. The second vacuum being sufficient to draw the portion of the fastener into the sealed cavity, while the first vacuum level is not sufficient to draw the portion of the fastener into the sealed cavity.  
           [0009]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:  
         [0011]    [0011]FIGS. 1 a  and  1   b  represent cross-sectional views of the rivet setting tool having a mandrel collection system according to the teachings of the present invention;  
         [0012]    [0012]FIG. 2 represents an exploded view of the mandrel collection system shown in FIG. 1 a;    
         [0013]    FIGS.  3 - 8  represent the air supply module for the mandrel control system shown in FIG. 1;  
         [0014]    [0014]FIGS. 9 a - 9   d  represent the vacuum control module shown in FIG. 2;  
         [0015]    [0015]FIGS. 10 a - 10   b  represent the mandrel collection system body shown in FIG. 2;  
         [0016]    [0016]FIGS. 11 a - 11   b  represent cross-sectional and side views of the mandrel collection system shown in FIG. 1;  
         [0017]    [0017]FIGS. 12 a - 12   b  represent side cross-sectional views of the mandrel collection system coupled to a hydraulic actuator of the rivet setting tool;  
         [0018]    [0018]FIGS. 13 a - 13   b  represent close up cross-sectional views of the interaction of the hydraulic actuator with the mandrel collection system;  
         [0019]    FIGS.  14 - 15  show cross-sectional views of the functioning of the mandrel collection system;  
         [0020]    [0020]FIGS. 16 a - 16   b  show close ups of a control valve within the vacuum control mechanism; and  
         [0021]    [0021]FIG. 17 represents three styles of notches used in the hydraulic actuator of the rivet setting tool.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]    The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.  
         [0023]    With reference to FIGS. 1 a  and  1   b  which show a rivet setting tool  30  having a mandrel collection system  32  according to the teachings of the present invention. The mandrel collection system is formed of four components that are axially fixed to the rivet setting tool  30 . The mandrel collection system  32  is formed of an air supply module  34 , a vacuum control module  36 , a collector bottle  38 , and a mandrel collection system body  40 . The mandrel collection system  32  provides a mechanism which is capable of automatically switching from a “low vacuum” level to a “high vacuum” level for a predetermined amount of time. In this regard, the system is configured to provide a low vacuum state when the rivet setting tool is not being actuated and a “high vacuum” state for when a mandrel must be drawn from the actuating head  42  of the rivet setting tool  30 . The air supply module  34  contains a switch mechanism to activate the mandrel collection system  32  and supply the vacuum control module  34  with air to generate a vacuum. The collector bottle stores spent rivet mandrels pulled in from the tool via the vacuum control module  36 .  
         [0024]    The mandrel collection system  32  uses movement of the rivet setting tools&#39; actuation hydraulic piston  44  to actuate the mandrel collection system  32 . Upon actuation of the actuating head  42  of the rivet setting tool  30 , the movement of the actuating piston  44  causes the mandrel collection system  32  to increase the amount of vacuum within a collection bottle to draw the rivet mandrel through the rivet mandrel collection tube  46  defined within the actuation piston  44 . When the mandrel collection system  32  is activated or “turned on” via the switch mechanism in the air supply module  34 , a constant vacuum is generated by the vacuum control module  36 . The level of the constant vacuum is regulated by a needle valve (as disclosed below). This level can be adjusted all the way from full vacuum capability of the mandrel collection system to completely off.  
         [0025]    [0025]FIG. 1 b  represents a cross-sectional view of mandrel collection system  32  shown in FIG. 1 a . The mandrel collection system  32  is coupled to an aft portion  47  of the rivet setting tool  30  using a coupling mechanism. In this regard, the coupling mechanism can be a threaded flange or the mandrel collection system  32  can be coupled to the rivet setting tool  30  using a number of threaded fasteners. Additionally, the mandrel collection system  32  can be coupled to the rivet setting tool  30  using a snap ring assembly or other applicable coupling mechanisms.  
         [0026]    The mandrel collection system  32  defines a through bore  60  that slidably accepts the mandrel collection actuator  48  of the actuating piston  44 . Additionally, the mandrel collection system  32  defines a compressed air inlet  70  that receives compressed air from the rivet setting tool  30 . The compressed air supply  70  functions to provide compressed air to the vacuum control module and a valving mechanism  64  within the mandrel collection system  32 .  
         [0027]    Inside the vacuum control module  36  is a valve mechanism. In the constant vacuum or low flow mode, the valve mechanism is in a closed position allowing air to pass down a low flow path and sealing a high flow path causing a vacuum transducer to generate a constant “low vacuum” level. This low vacuum level is obtained by restricting the flow of the vacuum transducer via a flow control needle valve. The high flow mode of the mandrel control system  32  is activated by supplying air pressure to the chamber at the bottom of the valve and pushing the valve up to a high flow position via air pressure over differential areas. The air is supplied via an air valve located on the actuating piston  44  of the rivet setting tool  30  which is actuated when the tool is cycled. When the valve is opened, the air supply from the air supply module  34  is allowed to bypass the restriction from the needle valve and goes directly to the vacuum transducer, creating a high vacuum condition from the full, unrestricted flow of the supply. When the cycle of the tool is completed, the air supply to the valve is cut off. Once the supply is cut off, the air pressure begins to reduce back to atmospheric pressure via a bleed orifice that is ported off the air chamber beneath the valve. The pressure “leaks” out at a rate dependent on the size of the orifice. It, therefore, takes a certain period of time for the chamber beneath the valve to evacuate. This “bleed off” time is the timer mechanism for the mandrel collection system  32 . As the chamber evacuates, the valve begins to close, closing off the high flow air path and restoring the mandrel collection system to a low flow mode. A detailed description of the functioning of the system and its components is made below.  
         [0028]    [0028]FIG. 2 represents a perspective exploded view of the mandrel collection system  32  shown in FIGS. 1 a  and  1   b . Shown are the air supply module  34 , the vacuum control module  36 , the collector bottle  38 , and the mandrel collection system body  40 . The mandrel collection system  32  is configured so the mandrel collection system body  40  and collector bottle  38  define a collection vacuum chamber  71 . Further, the mandrel collection system body  40  couples to the air supply module  34  to enclose the vacuum control module  36 .  
         [0029]    FIGS.  3 - 8  represent views of the air supply module  34 . As best seen in FIG. 3, the exterior surface of the air supply module  34  defines a plurality of threaded bores  72  which are used to couple the vacuum control module  36  and the mandrel collection system body  40  to the air supply module  34 . As seen in FIGS. 3 and 5, the air supply module further defines an air exhaust port  74  for the release of compressed air from the vacuum control module  36  and the air supply module  34 .  
         [0030]    FIGS.  6 - 7  represent cross-sectional views of the air supply. Shown is a plurality of apertures and a chamber defined within the body of the air supply module  34 . Defined within the air supply module is the compressed air supply inlet  71  which functions to bring a constant air pressure from the rivet setting tool  30  into the valving mechanism  64  of the mandrel collection system  32 . Additionally defined within the body is a chamber, which is fluidly coupled to the central aperture. Additionally coupled to the central aperture is a chamber having a leak control orifice  76 . The leak control orifice  76  functions to use pressure built within the chamber to supply a stream of pressurized air to a shuttle valve as will be further described below.  
         [0031]    As seen in FIG. 8, the air supply module  34  defines a plurality of coupling orifices, which mate with a corresponding set of orifices in the vacuum control module and the mandrel collection system body  40 . Additionally, the air supply module defines a recessed portion  86 , which slidably accepts a post portion  88  of the vacuum control module  36 .  
         [0032]    As best seen in FIGS. 6 and 7, the leak control aperture  90  is configured of two separate sections. The first portion  92  has a first diameter, while the second section has a second diameter  94 . Disposed within the second section is a 0.005 inch disk having an aperture formed by the use of a laser. The aperture in the disk has a diameter of about 0.0012 to 0.0025 inches in diameter. Modification of the diameter of the aperture as well as the pressure regulates the timing of the actuation of the vacuum control module  36 .  
         [0033]    As previously mentioned, the air supply module  34  has a through bore  60 . Axially disposed about the through bore is a first groove  94  that holds a first O-ring  96 . Also disposed about the through bore is a shelf portion  98  that holds a second O-ring  100 . The first O-ring  96  functions in conjunction with one or more longitudinally formed slots or chamfers  102  defined within the actuating piston  44  to form a gas actuator as further described below.  
         [0034]    [0034]FIGS. 9 a - 9   d  represent views of the vacuum control module  36 . The vacuum control module  36  defines a plurality of input ports and output ports. Similarly, disposed within the air control module  34  is a plurality of interconnected apertures with a set of corresponding valves which effect the production of a vacuum within the vacuum control module  36 .  
         [0035]    As best seen in FIG. 9 d , the vacuum module  36  defines a shuttle valve chamber  104 , a constant/low flow needle valve control chamber  106 , and a vacuum transducer chamber  108 . Further disclosed within the system is a constant air supply passage  110  which coupled to the constant air supply  70 . Further defined within the vacuum control module is a low flow passage  112  and a high flow passage  114 . The function of these passages and chambers will be described in detail below.  
         [0036]    [0036]FIGS. 10 a - 10   b  represent a module collection system body  40 . As can be seen, the module collection system body defines a through bore  60  that slidably accepts the hydraulic piston. Defined at one end of the coupling member is a vacuum or aperture  116  that fluidly couples the collector bottle  38  to the vacuum supply line  118  defined within the vacuum control module  36 .  
         [0037]    [0037]FIGS. 11 a  and  11   b  represent side and end views of an assembled mandrel collection system  32 . Shown is the relationship between the orifices of the air supply module  34  and the vacuum control module  36 . Defined within the shuttle chamber is a shuttle valve  120  which functions to regulate the flow of pressurized air from the constant air supply  110  to a vacuum transducer  115  that is disposed within the vacuum transducer chamber  108 . As described below, the shuttle valve moves in response to movement of the actuating piston  44 . Movement of the shuttle valve  120  regulates the flow of air from the constant air supply  110  to cause it to either pass a needle control valve  126  formed within the constant low flow needle valve control chamber  106  or through the high flow path  114 . Flow of air through the vacuum transducer causes the vacuum port  118  to suck air into the venturi vacuum actuator, thus forming the vacuum within the collection bottle  38 .  
         [0038]    [0038]FIGS. 12 a - 12   b  show the activation of the mandrel collection system  32 . Shown is the actuator piston  44  in its forward and first position. As can be seen, the first and second O-rings fluidly seal the chamber for holding the activation piston  50  from the mandrel collection system  32 . Upon activation of the rivet setting tool  30 , the actuation piston  44  withdraws into the mandrel collection system through bore  60  and actuates the actuating head  42  of the rivet setting tool. When the actuation piston  44  moves to its second position, the air passage, in the form of the notch  102  formed within the piston actuator allows pressurized air from the chamber for holding the actuated piston to bypass the first O-ring  96  and pressurize the chamber defined within the air supply module  34 . The air path is provided by means of the notch  102  in the piston  44 , which is placed beneath the first o-ring  96 . This allows compressed air to flow from the chamber  50  to the mandrel collection system  32  to actuate the shuttle valve  120 . The pressure within chamber  50  is maintained at about 85 psi by supply orifice  52 .  
         [0039]    [0039]FIGS. 13 a  and  13   b  are close up cross-sectional views of the interaction between the actuation piston  44  and the air supply module. As seen, when the piston is in its second position, air bypasses the first O-ring and enters a control orifice  134 . The control orifice  134  is fluidly coupled to the shuttle valve chamber  104 , thus allowing flow through the orifice  134  to actuate the shuttle valve  120 . It is envisioned that other sources of compressed air could be fluidly coupled to the shuttle valve chamber  104  to actuate the shuttle valve  120 . The second o-ring  100  prevents compressed air from escaping from the chamber  50  into the collector bottle  38 . In the normal position, the notch  102  is not positioned under the first o-ring  96 . This prevents air from flowing from chamber  50  into the control orifice  134 .  
         [0040]    [0040]FIG. 14 represents the functioning of the mandrel collection system when the actuating piston  44  is in its first non-activated position. In this regard, the vacuum system generates a low level vacuum in the bottle. As can be seen, the shuttle valve  120  is in a non-actuated position. A constant flow of air is supplied through the constant air line  110  through the low flow passage  112  and past the constant low flow needle valve  113 . This low flow air passes through the venturi vacuum transducer  115  to form a low level vacuum at the vacuum supply port  118 .  
         [0041]    When the piston is moved into its second or actuated position (see FIG. 13 b ), air pressure passes the first O-ring  96  and enters the control orifice  134 . As seen in FIG. 15, this air pressure from the control orifice  134  actuates the shuttle valve  120  and causes it to move to a second position  140 . When the shuttle valve  120  is in its second position  140 , air from the constant pressure supply  70  line flows through both the low and high flow passages  112 ,  114 . This allows a high flow to enter the venturi vacuum actuator  115 , allowing a high or large vacuum to be drawn through the vacuum supply  118 . This high vacuum functions to pull the mandrel from the actuating head  42  and place the spent mandrel into the collection bottle  38 . After a predetermined amount o time, the piston  44  is returned to its normal position. Air pressure bleeds through the orifice  76 , returning the shuttle valve  120  to its unactuated position.  
         [0042]    [0042]FIGS. 16 a - 16   b  are closer figures of the constant flow needle valve  113 . In this regard, the position of a valve element  142  to a valve seat  144  is adjustable by a user by rotating a threaded member  146 . In doing so, the user is able to adjust the low vacuum pressure from zero to full vacuum. The valve element  142  can be formed of a series of stepped diameters. Each diameter is configured to allow a specific flow rate through the valve via a predetermined restriction based on the clearance of the valve element  142  to the valve seat  144 . For example, it is envisioned that while the high vacuum level would be sufficient to pull a mandrel, the low vacuum level may not.  
         [0043]    [0043]FIG. 17 represents varying styles of air passages in the form of the notch  102  that can be formed into the activation piston  44 . As can be seen, the profile of the notch  102  can be adjusted to vary the amount of flow to the control orifice  134 . In this regard, the size and depth of the orifice may be adjusted to accommodate necessary flows without cutting the first O-ring.  
         [0044]    The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. For example, while a rivet setting tool is disclosed, the teachings of the present invention are equally applicable to other fastening tools. Additionally while the system is disclosed for removing a rivet mandrel, it is possible to use the teachings of the present invention in a fastener feeding system. Such variations are not to be regarded as a departure from the spirit and scope of the invention.