Sealed parking brake section for tamper resistant brake actuator

Abstract

An improved tamper resistant brake actuator for sealing the pressurized parking brake section and inhibiting the unauthorized disassembly thereof. The spring housing has a first annular flange and the adapter base has a second annular flange that are cooperatively configured to define an annular channel when they are joined together. The periphery of the parking chamber diaphragm is provided with an expanded portion, preferably an integral o-ring, that sealably fits within the annular channel when the two annular flanges are engaged so as to provide radial sealing for the parking brake section. A ring-shaped annular retaining member or clamp is circumferentially disposed about the interface of the flanges and diaphragm periphery and is secured with a connecting mechanism that inhibits disassembly of the adapter base. The ends of the retaining member can be crimped, welded or bolted/riveted together. The retaining member is not required to axially clamp the diaphragm periphery.

1 . A tamper resistant brake actuator, comprising: 
 a spring housing having a first annular flange;    an adapter base having a second annular flange, said spring housing and said adapter base joined at said first annular flange and said second annular flange;    an annular channel defined by said first annular flange and said second annular flange;    a generally flexible diaphragm having an expanded portion at a periphery thereof, said expanded portion sealably disposed in said annular channel, said first annular flange, said second annular flange and said expanded portion defining an interface, said expanded portion sealingly engaging said annular channel in a generally radial direction; and    an annular retaining member secured about said interface, said annular retaining member having a pair of spaced apart inwardly protruding portions, one of said inwardly protruding portions in engagement with said first annular flange and the other of said inwardly protruding portions in engagement with said second annular flange, said annular retaining member configured so as to inhibit separation of said spring housing and said adapter base.    
     
     
         2 . The brake actuator of  claim 1 , wherein said first annular flange has a generally radially outwardly extending shoulder and a generally downwardly extending collar and said second annular flange has a generally upwardly extending collar and a generally radially outwardly extending shoulder extending outward from the base of said collar.  
     
     
         3 . The brake actuator of  claim 2 , wherein said annular channel is defined by said shoulder and said collar of said first annular flange and said collar and said shoulder of said second annular flange.  
     
     
         4 . The brake actuator of  claim 2 , wherein said pair of inwardly protruding portions comprises a first inwardly protruding portion and a spaced apart second inwardly protruding portion defining a clamp channel therebetween, said first inwardly protruding portion in engagement with said shoulder of said first annular flange and said second inwardly protruding portion in engagement with said shoulder of said second annular flange, said clamp channel generally abutting said interface.  
     
     
         5 . The brake actuator of  claim 1 , wherein expanded portion comprises an integral o-ring.  
     
     
         6 . The brake actuator of  claim 1 , wherein said pair of inwardly protruding portions comprises a first inwardly protruding portion and a spaced apart second inwardly protruding portion defining a clamp channel therebetween, said first inwardly protruding portion in engagement with said first annular flange and said second inwardly protruding portion in engagement with said second annular flange, said clamp channel generally abutting said interface.  
     
     
         7 . The brake actuator of  claim 1  further comprising means for securing a first end of said annular retaining member to a second end of said annular retaining member so as to further inhibit separation of said spring housing and said adapter base.  
     
     
         8 . The brake actuator of  claim 7 , wherein said securing means comprises an outer connector at said first end of said annular retaining member and an inner connector at said second end of said annular retaining member, said outer connector having one or more bendable tabs configured to engage a center section of said inner connector.  
     
     
         9 . The brake actuator of  claim 8 , wherein said securing means further comprises one or more retaining tabs on said inner connector, said retaining tabs configured to prevent separation of said first end and said second end of said annular retaining member.  
     
     
         10 . The brake actuator of  claim 7 , wherein said securing means comprises an outer connector at said first end of said annular retaining member and an inner connector at said second end of said annular retaining member, said outer connector having one or more apertures.  
     
     
         11 . The brake actuator of  claim 10 , wherein at least one of said one or more apertures overlays a weld receiving area on said inner connector, said outer connector and said inner connector interconnected by a weld.  
     
     
         12 . The brake actuator of  claim 11 , wherein said inner connector comprises a tab extension member at said second end of said annular retaining member, said weld receiving area on said tab extension.  
     
     
         13 . The brake actuator of  claim 10 , wherein at least one of said one or more apertures of said outer connector overlays an aperture in said inner connector, said apertures of said outer connector and said aperture of said inner connector sized and configured to receive a connecting element therein, said connecting element configured to securedly connect said first end and said second end of said annular retaining member.  
     
     
         14 . The brake actuator of  claim 13 , wherein said securing means further comprises a nut at said inner connector.  
     
     
         15 . The brake actuator of  claim 1 , wherein said annular retaining member comprises a two or more clamp sections disposed about said interface to form a generally continuous curvilinear member, each of said clamp sections having a first end securedly joined to a second end of an adjacent clamp section.  
     
     
         16 . A tamper resistant brake actuator, comprising: 
 a spring housing having a first annular flange, said first annular flange comprising a generally radially outwardly extending shoulder and a generally downwardly extending collar;    an adapter base having a second annular flange, said second annular flange comprising a generally upwardly extending collar and a generally radially outwardly extending shoulder, said shoulder extending outward from the base of said collar, said spring housing and said adapter base joined at said first annular flange and said second annular flange;    an annular channel defined by said shoulder and said collar of said first annular flange and said collar and said shoulder of said second annular flange;    a generally flexible diaphragm having an expanded portion at a periphery thereof, said expanded portion sealably disposed in said annular channel, said first annular flange, said second annular flange and said expanded portion defining an interface;    an annular retaining member having a first inwardly protruding portion and a spaced apart second inwardly protruding portion defining a clamp channel therebetween, said first inwardly protruding portion in engagement with said shoulder of said first annular flange and said second inwardly protruding portion in engagement with said shoulder of said second annular flange, said clamp channel generally abutting said interface; and    means for securing a first end of said annular retaining member to a second end of said annular retaining member around said interface so as to inhibit separation of said spring housing and said adapter base.    
     
     
         17 . The brake actuator of  claim 16 , wherein said securing means comprises an outer connector at said first end of said annular retaining member and an inner connector at said second end of said annular retaining member, said outer connector having one or more bendable tabs configured to engage a center section of said inner connector.  
     
     
         18 . The brake actuator of  claim 17 , wherein said securing means further comprises one or more retaining tabs on said inner connector, said retaining tabs configured to prevent separation of said first end and said second end of said annular retaining member.  
     
     
         19 . The brake actuator of  claim 16 , wherein said securing means comprises an outer connector at said first end of said annular retaining member and an inner connector at said second end of said annular retaining member, said outer connector having one or more apertures.  
     
     
         20 . The brake actuator of  claim 19 , wherein at least one of said one or more apertures overlays a weld receiving area on said inner connector, said outer connector and said inner connector interconnected by a weld.  
     
     
         21 . The brake actuator of  claim 20 , wherein said inner connector comprises a tab extension member at said second end of said annular retaining member, said weld receiving area on said tab extension.  
     
     
         22 . The brake actuator of  claim 19 , wherein at least one of said one or more apertures of said outer connector overlays an aperture in said inner connector, said apertures of said outer connector and said aperture of said inner connector sized and configured to receive a connecting element therein, said connecting element configured to securedly connect said first end and said second end of said annular retaining member.  
     
     
         23 . The brake actuator of  claim 22 , wherein said securing means further comprises a nut at said inner connector.  
     
     
         24 . The brake actuator of  claim 16 , wherein said annular retaining member comprises two or more clamp sections disposed about said interface to form a generally continuous curvilinear member, each of said clamp sections having a first end securedly joined to a second end of an adjacent clamp section.  
     
     
         25 . A method of sealably securing a spring housing to an adapter base for a tamper resistant brake actuator, said method comprising the steps of: 
 a. providing said spring housing with a first annular flange and said adapter base with a second annular flange;    b. providing a flexible diaphragm having a periphery comprising an expanded portion;    c. placing the periphery of said flexible diaphragm on said second annular flange, said expanded portion disposed circumferentially about said annular flange;    d. placing said spring housing over said flexible diaphragm with said first annular flange in substantial alignment with said second annular flange and said expanded portion of said flexible diaphragm;    e. applying sufficient force to said spring housing and/or said adapter base to push said first annular flange over said expanded portion of said flexible diaphragm, said first annular flange and said second annular flange defining an annular channel, said expanded portion sealably disposed in said annular channel, said expanded portion forming a radial seal in said annular channel;    f. installing an annular retaining member about an interface of said first annular flange, said second annular flange and said expanded portion of said flexible diaphragm, said annular retaining member having a first end and a second end; and    g. securing said first end of said annular retaining member to said second end of said annular retaining member so as to inhibit unauthorized disassembly of said brake actuator.    
     
     
         26 . The method of  claim 25 , wherein said first annular flange has an outwardly extending shoulder and a downwardly extending collar and said second annular flange has an upwardly extending collar and an outwardly extending shoulder extending outwardly from the base of said collar, said shoulder and said collar of said first annular flange and said collar and said shoulder of said second annular flange forming said annular channel.  
     
     
         27 . The method of  claim 25 , wherein said first end of said annular retaining member comprises an outer connector and said second end of said annular retaining member comprises an inner connector.  
     
     
         28 . The method of  claim 27 , wherein said securing step comprises crimping one or more inwardly bendable tabs on said outer connector over a center section of said inner connector.  
     
     
         29 . The method of  claim 28 , wherein said annular retaining member further comprises one or more retaining tabs on said inner connector, said one or more retaining tabs configured to prevent separation of said first end and said second end of said annular retaining member.  
     
     
         30 . The method of  claim 27 , wherein said outer connector comprises one or more apertures, said one or more apertures overlying a weld receiving area on said inner connector, said outer connector and said inner connector joined with a weld in said aperture.  
     
     
         31 . The method of  claim 30 , wherein said inner connector comprises a tab extension, said weld receiving area on said tab extension.  
     
     
         32 . The method of  claim 27 , wherein said outer connector comprises one or more apertures overlying at least one aperture in said inner connector, said aperture in said outer connector and said aperture in said inner connector configured to receive a connecting element therein.