Abstract:
The present electric horn system includes a monolithic rigid housing member having a receiving opening for fixably housing, in an non-removable and secure manner following assembly, a compressor member, thereby preventing unintended separation and improving a reliability of the electric horn system. An acoustic sound wave generator includes an acoustic duct chambering system associated throughout with the monolithic rigid housing member. The acoustic sound wave generator receives compressed air from the compressor member to produce sound and propagate the same externally. A horn mounting system enables ready attachment of the system to a consumer-desired surface; either mechanically, magnetically, adhesively or via any other known attachment or mounting system. Optional weather and water resistant systems prohibit unintended water access to the electric horn system enabling use of the system in exposed weather conditions for improved user convenience.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   This application cross references and claims priority from U.S. Prov. App. Ser. Nos. 60/970,365 filed Sep. 6, 2007, 60/979,525 filed Oct. 12, 2007, and 61/059,172 filed Jun. 5, 2008, the entire contents of each of which are also incorporated herein by reference. 

   FIGURE SELECTED FOR PUBLICATION 
   
     FIG. 8 
   
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to an electric horn system. More specifically, the present invention relates to an electropneumatic horn system adapted for multiple commercial uses wherein a compressed air generating unit is securely fixed within a monolithic housing during an assembly and enables multi-tonal, particularly bi-tonal sound generation, during a use. 
   2. Description of the Related Art 
   The related art involves generally electric and electropneumatic horn constructions and systems. Electropneumatic horns are those which generate sound by generated air flow or compressed air and are considered (very broadly due to their typical electrical operation of compressed air or air-supply valving) to be within the wider grouping of electric horns due to the electric control of the generation of the air flow or compressed air. It should be noted that electric horn constructions also include (in addition to pneumatic sound creation) the creation of electronic sound (e.g. speaker type systems) wherein sound or tone is the result of an electronic signal to a speaker and not the result of an acoustic passage. As a consequence, those of skill in the art will recognize that the use of the phrases electronic, electrical, and electropneumatic shall be considered non-limiting in the following description. 
   Conventionally, electropneumatic horns include acoustic units consisting of a straight exponential tube of a length related to the frequency to be reproduced, inserted in an acoustic chamber in which a membrane free to move with a reciprocating motion is arranged and positioned. 
   Conventionally, the straight tube comprises a first stretch with generally constant cross-section, provided with an inlet mouth for the sound signal generated by the oscillating membrane and a second stretch having a section varying with a generally conic exponential law ending with an outlet mouth for the amplified sound signal (e.g., horn shaped). 
   As used in these conventional electropneumatic horns, the membrane is properly stretched or positioned during a pre-assembly calibration phase by deformation against the membrane of a member referred to as a ‘sound generator’ and applied to a chamber body, in such a way to generate a sound with manufacturer-desired predetermined acoustic pressure during a use. 
   In an alternatively constructed versions of the related art, the acoustic units are paired (commonly bi-tonal), and the corresponding tubes are volute wound and juxtaposed to limit the overall dimensions of the horn allowing for reduced-size installations. 
   As already stated said acoustic horns and more particularly those with a straight acoustic tube (e.g., ‘truck air horns’), equip motor vehicles and are generally installed in the engine compartments and on vehicle roofs. 
   Acoustic horns with different features are available on the market, both by others and by the present Applicant, and are mainly classified according to the number of acoustic units, generally one to a general maximum of three tuned tonal sounds, each shaped according to the frequency that each unit should reproduce. 
   The need to optimize space and reduce dimensions of every element of the motor vehicle, has lead to the reduction in size of such electropneumatic acoustic horns generally, and the miniaturization of specific horn components. For example, it is known to reduce the size of the air compressor unit or member as well as reduce the overall size of the acoustic sound units. 
   Referring now to U.S. Pat. No. 7,038,756 (Di Giovani et al), the entire contents of which are herein incorporated by reference, and  FIG. 1  and  FIG. 1A , since the earlier proposed solutions had not garnered sufficient success, the &#39;756 patent attempted to respond to the needs in the art by providing a dual tone or dual acoustic unit wherein a completed assembly  1  accommodates dual acoustic units having respective horn openings  4 A,  4 B within a relatively compact housing  2 . 
   In this related unit, housing  2  contains a single compressor unit or compressor member  6  which is removably and slidably joined within an adjustable clamp to housing  2  and provides a compressed air supply via air supply outlet fixture  13  simultaneously to each acoustic unit within housing  2  via internal chambering. 
   As also noted dual opposing diaphragm units  3 ,  3  are shown and respectively receive, via internal chambering (not shown but visible in the &#39;756 patent) compressed air from compressor unit  6  via respective diaphragm air supply portals  16 ,  16  (the reverse side is not shown). Diaphragm units  3 ,  3 , operate as sound generators and transmit the sound to the volute acoustic chambers respectively connecting each diaphragm unit  3 ,  3  to respective horn openings  4 A,  4 B. 
   Compressor unit  6  consists of an operable motor housing member  14  formed from a very rigid metal body, a bottom electric brush housing member  10 , wherein electrical power is received via power supply cords  5 , and a top compressor labyrinth member  9 . As will be noted from  FIG. 1 , rigid housing member  14  includes folded metal tabs  15  serving as engagement fingers joining motor housing  14  to top compressor labyrinth member  9  to prevent unintended separation and reliable operation. Typically, bottom electronic brush housing member  10  is secured to rigid housing member  14  via a plurality of removable and accessible snap-in fittings (not shown), allowing ease of assembly. Unfortunately, this ease of assembly also creates relative structural weaknesses in the overall completed assembly  1  that may serve as a source of future failure (as will be discussed). 
   Housing  2 , includes a pair of opposing C-shaped plastic clamp arms  7 A,  7 B as shown for slidably and removably gripping portions of the external surface of rigid housing member  14 . Additionally, an air tube member  11 , having an air intake opening  12  is formed along the wall of the first clamp arm  7 B and supplies air to a top air opening or inlet (not shown) in compressor to member  9 . Additionally, a single mounting bracket member  17 , extends rearwardly from compressor unit  6  and compressor pump member  9  allowing attachment to a weather-dry location within an inner vehicle wall mount position (not shown). As noted earlier, system  1  contains a number of relative structural weaknesses, and mounting bracket member  17  a common location for structural failure. As can be recognized from the cantilever construction shown, mounting bracket  17  provides a single-site attachment mechanism, which preferentially fails when used in high-vibration environments, including automotive and motorcycle mounting environments. 
   Additionally, it shall be recognized by those of skill in the art that opposing paired clamping arms  7 A,  7 B slidingly receive compressor unit  6 , and consequently that even with air outlet fixture  13  providing an additional engagement with housing  2 , the construction taught in &#39;576 often results in the mechanical failure causing separation of compressor unit  6  because there is no physical engagement between the body of the compressor unit  6  and housing  2  other than air outlet fixture  13 , and because there is no mechanism to maintain the tension between clamp arms  7 A,  7 B to ensure and maintain a clamping pressure, particularly during the thermal expansion common in plastic housings when employed in high temperature environments common in vehicle wall mounting positions. As a consequence of this tendency for mechanical failure, those who review the mechanical units marked with the &#39;576 patent note the inclusion of an additional adhesive double-tape stick portion  8  between portions of clamp arm members  7 A,  7 B and portions of the wall surfaces of motor housing  14 . 
   The use of such double-stick tape  8 ,  8  is unfortunately also problematic since it does not address the initial structural design weakness in the engagement between housing  2  and compressor unit  6 , and because such adhesive tape readily fails for a number of reasons, including; (a) degradation, melting, off-gassing, or embrittlement of the adhesive in high temp (&gt;100 Celsius) and low temp (&lt;O Celsius) common in standard vehicle mounting environments or (b) mechanical failure of the tape backing structure itself. Since the related art recognizes the preferred use of unit  1  within the automotive engine cavity, where temperatures routinely exceed 100 Celsius, this thermal and mechanical weakness has resulted in unacceptable failure rates. Since the related art also recognizes the preferred use of unit  1  within the marina and water environments, where chemical reaction with the enhanced humidity and corrosive environment attacks adhesives, this material degradation has resulted in a similarly unacceptable failure rate. 
   As an additional detriment of the conventional construction discussed, while internal splash baffles (not shown) are discussed in &#39;576 within air intake tube  11 , it will be recognized that horn openings  4 A,  4 B are on the same level with air opening  12  for the compressor air intake, and are not similarly protected due to impact such rigid baffles would have on sound tone and overall sound quality. Therefore, while water penetration within the acoustic tubes via respective horn openings  4 A,  4 B is no less a danger then water penetration to air inlet tube  11 , the related art has not recognized this detriment and has similarly not provided a solution. Consequently, while water-splashing and moisture may readily damage unit  1  via entry to horn openings  4 A,  4 B even while the unit is within a contained environment, for example an automotive engine cavity, there is an unsatisfied need for substantive improvements in weather and water resistance recognized within the related art. Therefore, there is a need for a weather resistant solution that has minimal or no impact on the generated tonal or sound quality. 
   Additionally of concern are circumstances wherein the unit is employed as a full replacement for an originally-manufactured horn for a vehicle. Where full replacement use occurs, consumers have no other alternative for emergency use, and consequently the horn must operate at the highest levels of reliability and safety. 
   What is not appreciated by the prior art therefore, is the need for an improved system comprising a compressor unit and housing member that avoids at least one of the detriments noted earlier so as to provide improved unit operational reliability, as well as operability, minimize mechanical and thermal failures within a wide field of user environments. 
   Accordingly, there is a need for an improved electric horn system, and more specifically and improved electropneumatic horn system that responds to one of detriments noted above. 
   OBJECTS AND SUMMARY OF THE INVENTION 
   An object of the present invention is to provide an electric horn system that overcomes at least one of the detriments noted above. 
   Another aspect of the present invention is to provide an electric horn system, wherein an electropneumatic horn is provided with an improved and reliable connection between a housing and a compressor unit. 
   Another aspect of the present invention is to provide an electropneumatic horn system having increased resistance to vibration, thermal challenge, and chemical or environmental/weather related extremes. 
   Another aspect of the present invention is to provide an improved electropneumatic horn system operable at increased weather, environmental, and temperature extremes. 
   The present invention relates to an electric horn system includes a monolithic rigid housing member having a receiving opening for fixably housing, in an non-removable and secure manner following assembly, a compressor member, thereby preventing unintended separation and improving a reliability of the electric horn system. An acoustic sound wave generator includes an acoustic duct chambering system associated throughout with the monolithic rigid housing member. The acoustic sound wave generator receives compressed air from the compressor member to produce sound and propagate the same externally. A horn mounting system enables ready attachment of the system to a consumer-desired surface; either mechanically, magnetically, adhesively or via any other known attachment or mounting system. Optional weather and water resistant systems prohibit unintended water access to the electric horn system enabling use of the system in exposed weather conditions for improved user convenience. 
   The present invention also relates to an electric horn system that allows permanent and irremovable attachment between the monolithic rigid housing member and the compressor member via a series of one-way attachment features preventing unintended separation. 
   The present system additionally relates to an electric horn system that completely surrounds the compressor member offering protection 360 degrees about an outer periphery of the compressor member. 
   According to an embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, comprising: an electric compressor unit having at least a compressor air inlet and a compressor air outlet for the supply of compressed air, a sound wave generator system substantially housed in a monolithic housing assembly, the sound wave generator system comprising: at least one acoustic chamber having an opening for the introduction of the pressurized air, a membrane member provided with an opening for sound generation and at least one acoustic duct housed in the monolithic housing assembly and communicating between the at least one acoustic chamber and at least one horn outlet to propagate the sound generated by the membrane member outside the horn, air channeling means for communicating between the compressor air outlet of the electric compressor unit and the opening of the at least one acoustic chamber, means for permanently fixing the electric compressor unit in the monolithic housing assembly of the sound wave generator system, whereby the means for irremovably fixing prevents removal of the electric compressor unit and improves operational reliability of the assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, wherein: the monolithic housing assembly includes a monolithic compressor housing portion having a cylindraceous receiving opening, the electric compressor unit being cylindraceous and having a first and opposing second end, the first end of the electric compressor unit being a compressor member, an electrical brush housing portion at the second opposing end, a motor housing joining the electric compressor unit and the electrical brush housing portion, the means for permanently fixing further comprising: spring engagement means for elastically engaging and permanently fixing the cylindraceous electric compressor unit in the cylindraceous receiving opening, thereby improving the reliability of the assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, wherein: the cylindraceous receiving opening includes opening side walls, the cylindraceous compressor unit having compressor side walls, the opening side walls and the compressor side walls being juxtaposed with each other upon an assembly of the electropneumatic acoustic horn assembly, and the spring engagement means including at least one spring locking tab member and at least one corresponding locking tab receiving groove, whereby during the assembly of the electropneumatic acoustic horn assembly the at least one spring locking tab urgingly engages the corresponding locking tab receiving groove and prevents removal of the compressor unit from the receiving opening. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, wherein: the spring engagement means includes a plurality of the spring locking tab members and a corresponding plurality of the corresponding locking tab receiving grooves, and respective ones of the plurality of tab members and the receiving grooves arrayed about respective ones of the receiving opening and the compressor side walls. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, further comprising: means for aligning the cylindraceous compressor unit and the compressor air outlet with the opening in the acoustic chamber for the introduction of the pressurized air, the means including at least one alignment member and at least one alignment groove having complementary shapes for interfitting during the assembly, whereby the alignment member and the groove are slidingly arranged to align the compressor air outlet with the opening. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, wherein: the at least one horn outlet includes means for minimizing at least one of a debris and a water entry during a use of the assembly, and the means for minimizing includes at least one selected from a group comprising: an opening seal sealing the at least one horn outlet, at least one flexible louver member flexibly covering the at least one horn outlet, at least one flexible shield member pivotably covering the at least one horn outlet, and at least one of a woven and a metal mesh, whereby the at least one minimizing means enables a release of sound from the at least one horn outlet while minimizing entry of debris and water into the monolithic housing assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, further comprising: at least one housing air inlet passage in the monolithic housing assembly, at least one compressor air inlet passage in the monolithic housing assembly communicating from the at least one housing air inlet passage to the compressor air inlet, at least one air inlet including at least one means for minimizing at least one of a debris and a water entry during a use of the assembly, and the means for minimizing includes at least one selected from a group comprising: an opening seal sealing the at least air inlet, at least one flexible louver member flexibly covering the at least one air inlet, at least one flexible shield member pivotably covering the at least one air inlet, and at least one of a woven and a metal mesh covering the at least one air inlet, whereby the at least one minimizing means enables entry of feed air to the electric compressor air unit while minimizing entry of debris and water into the monolithic housing assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, further comprising: at least one housing air inlet passage in the monolithic housing assembly, at least one compressor air inlet passage in the monolithic compressor housing portion communicating from the at least one housing air inlet passage to the compressor air inlet, and the means for minimizing includes at least one selected from a group comprising: an opening seal sealing the at least one air inlet, at least one flexible louver member flexibly covering the at least one air inlet, at least one flexible shield member pivotably covering the at least one air inlet, and at least one of a woven and a metal mesh covering the at least one air inlet, whereby the at least one minimizing means enables entry of feed air to the electric compressor air unit while minimizing entry of debris and water into the monolithic housing assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, wherein: the at least one housing air inlet passage in the monolithic housing assembly is proximate the electrical brush housing portion at the second opposing end, and the at least one compressor air inlet passage extends from the air inlet passage through the monolithic housing assembly to the compressor air inlet at the first end of the electric compressor unit. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, further comprising: means for securing the monolithic housing assembly to an external support member, and the means for securing including at least one selected from the group comprising: a protruding mounting bracket member, a magnetic mounting member, a suction-based mounting member, an adhesive mounting member, and a strap mounting member, whereby the means for securing enables ready attachment of the assembly to the external support member. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, comprising: a cylindraceous electric compressor unit having at least a compressor air inlet and a compressor air outlet for the supply of compressed air, and a first and opposing second end, a sound wave generator system substantially housed in a monolithic housing assembly, the monolithic housing assembly having a monolithic compressor housing portion having a cylindraceous receiving opening, the sound wave generator system comprising: at least one acoustic chamber having an opening for the introduction of the pressurized air, a membrane member provided with an opening for sound generation and at least one acoustic duct housed in the monolithic housing assembly and communicating between the at least one acoustic chamber and at least one horn outlet to propagate the sound generated by the membrane member outside the horn, air channeling means for communicating between the compressor air outlet of the electric compressor unit and the opening of the at least one acoustic chamber, means for permanently fixing the electric compressor unit in the monolithic housing assembly of the sound wave generator system, whereby the means for irremovably fixing prevents removal of the electric compressor unit and improves operational reliability of the assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, wherein: the first end of the electric compressor unit being a compressor member, a motor housing fixably joining the electric compressor unit, the means for permanently fixing further comprising: spring engagement means for elastically engaging and permanently fixing the cylindraceous electric compressor unit in the cylindraceous receiving opening, thereby improving the reliability of the assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, further comprising: an electrical brush housing portion, means for securing the electrical brush housing portion at the second opposing end of the electric compressor unit, and the means for securing the electrical brush housing portion being one of a removable means for securing and a permanent means for securing. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, further comprising: means for sealing the electrical brush housing portion to a sealing surface of the monolithic compressor housing portion, whereby the means for sealing minimizes one of a debris and a water entry to the electric compressor unit and improves operational reliability of the assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, wherein: the springing engagement means includes a plurality of the springing locking tab members and a corresponding plurality of the corresponding locking tab receiving grooves, and respective ones of the plurality of tab members and the receiving grooves are arrayed about respective ones of the receiving opening and the compressor side walls. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, further comprising: means for aligning the cylindraceous compressor unit and the compressor air outlet with the opening inlet in the acoustic chamber for the introduction of the pressurized air, the means including at least one alignment member and at least one alignment groove having complementary shapes for interfitting during the assembly, whereby the alignment member and the groove are slidingly arranged to align the compressor air outlet with the opening. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, wherein: the means for permanently fixing the electric compressor unit in the monolithic housing assembly of the sound wave generator system further comprises, at least one of a group comprising: spring engagement means for elastically engaging and permanently fixing the cylindraceous electric compressor unit in the cylindraceous receiving opening, thermal welding means for thermally welding portions of the cylindraceous electric compressor unit with the monolithic compressor housing portion, and adhesively fixing means for adhesively bonding portions of the cylindraceous electric compressor unit with the monolithic compressor housing portion, whereby the means for permanently fixing improves operational reliability of the assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, wherein: the at least one horn outlet includes means for minimizing at least one of a debris and a water entry into the horn outlet during a use of the assembly, and the means for minimizing includes at least one selected from a group comprising: an opening seal sealing the at least one horn outlet, at least one flexible louver member flexibly covering the at least one horn outlet, at least one flexible shield member pivotably covering the at least one horn outlet, and at least one of a woven and a metal mesh, whereby the at least one minimizing means enables a release of sound from the at least one horn outlet while minimizing entry of debris and water into the monolithic housing assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, further comprising: at least one housing air inlet passage in the monolithic housing assembly, at least one compressor air inlet passage in the monolithic compressor housing portion communicating from the at least one housing air inlet passage to the compressor air inlet, at least one air inlet including at least one means for minimizing at least one of a debris and a water entry during a use of the assembly, and the means for minimizing includes at least one selected from a group comprising: an opening seal sealing the at least one air inlet, at least one flexible louver member flexibly covering the at least one air inlet, at least one flexible shield member pivotably covering the at least one air inlet, and at least one of a woven and a metal mesh covering the at least one air inlet, whereby the at least one minimizing means enables entry of feed air to the electric compressor air unit while minimizing entry of debris and water into the monolithic housing assembly. 
   According to another embodiment of the present invention there is provided an electropneumatic acoustic horn assembly, further comprising: means for securing the monolithic housing assembly to an external support member, and the means for securing including at least one selected from the group comprising: a protruding mounting bracket member, a magnetic mounting member, a suction-based mounting member, an adhesive mounting member, and a strap mounting member, whereby the means for securing enables ready attachment of the assembly to the external support member. 
   The above, and other objects, features and advantages of the present invention will become apparent from the following description read in conduction with the accompanying drawings, in which like reference numerals designate the same elements. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a front perspective view of a conventional electropneumatic horn assembly. 
       FIG. 1A  is a partial cross-sectional view along section line  1 A- 1 A in  FIG. 1 . 
       FIG. 2  is a front perspective view of a first embodiment of an electric horn system according to the present invention. 
       FIG. 2A  is an exploded view of the embodiment in  FIG. 2 . 
       FIG. 3  is a partial sectional perspective view of a wall section assembly of the embodiment in  FIG. 2 . 
       FIG. 4  is a partial sectional view of an alternative engagement feature between a compressor unit and the monolithic housing. 
       FIG. 5  is an exploded perspective view of a second alternative embodiment of an electric horn system according to the present invention. 
       FIG. 6  is an exploded perspective view of a third alternative embodiment of an electric horn system according to the present invention. 
       FIGS. 6A ,  6 B are close up views of alternative alignment means between the bonding surfaces noted in  FIG. 6 . 
       FIG. 7  is a front perspective view of a fourth embodiment of an electric horn system according to the present invention. 
       FIG. 7A  is a sectional view taken along the line  7 A-&amp;B in  FIG. 7 . 
       FIG. 8  is an exploded perspective view of the  FIG. 7  embodiment. 
       FIG. 9  is a partial view partly in section of the  FIG. 7  embodiment depicting the compressor unit mounting to the monolithic housing. 
       FIG. 10  is a fragmentary sectional view depicting the seal cap mounting attached to the bottom of the compressor unit. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Reference will now be made in detail to several embodiments of the invention that are illustrated in the accompanying drawings. Wherever possible, same or similar reference numerals are used in the drawings and the description to refer to the same or like parts or steps. The drawings are in simplified form and are not to precise scale. For purposes of convenience and clarity only, directional terms, such as top, bottom, up, down, over, above, and below may be used with respect to the drawings. These and similar directional terms should not be construed to limit the scope of the invention in any manner. The words “connect,” “couple,” and similar terms with their inflectional morphemes do not necessarily denote direct and immediate connections, but also include connections through mediate elements or devices. 
   Referring now to  FIGS. 2 ,  2 A,  3 , and  4  an alternative embodiment of an electropneumatic horn has been provided that overcomes at least one of the detriments in the related art noted above. 
   An electropneumatic horn unit  100  includes a rigid housing unit member  102  having a monolithic compressor housing region  107 , and an internally formed dual tonal acoustic ducting system (not shown). The dual tonal acoustic ducting system is similar to that shown in U.S. Pat. No. 7,038,576, and the entire contents of &#39;576 are herein again enclosed again by reference. The dual tone acoustic ducting system receives compressed air exiting a compressed air outlet  113 A of an air outlet fixture  113  from a compressor unit  106  (as will be discussed), passes the same via diaphragm members  103 ,  103  (only one shown) through a diaphragm air supply portal  116  so as to activate the same as sound generators. The sound so generated passes through the dual tone ducting system to exist via respective horn openings  104 A,  104 B. As will be additionally discussed the tone or sound generation functions of the proposed embodiment are related to those noted in the incorporated &#39;576 patent. 
   As will be noted from study of the renderings, compressor unit  106  having a bottom positioned brush housing member  110  and an opposing top sided compressor member  109  is completely surrounded by the monolithic body structure of housing unit  102  in the manner depicted. As will be discussed, a rear suspending bracket  117  is rearwardly projected from compressor member  109  in a manner familiar to those of skill in the art, although substantial improvements of this construction are noted in  FIGS. 3 ,  4 , and  5 , as will be later discussed to secure horn unit  100  to a desired position. 
   Compressor unit  106  includes an air intake opening  111 C proximate compressor member  109  ( FIG. 2A ), and when compressor unit  106  is operating dispenses compressed air via air outlet fixture  113 , as shown. Upon assembly, air outlet fixture  113  nests securely within air outlet receiving block  113 B in housing  102  which includes an air intake receiving opening (not shown) for receiving such generated compressed air for horn operation. 
   As will be noted a motor housing  114  spaces brush housing  110  from compressor member  109  and securely engages compressor pump member  109  via formed bent metal finger members  115  at periodic intervals about a periphery so as to ensure permanent attachment. The motor housing  114  has a metal shell to support metal finger members  115  but also includes optionally both (a) a plurality of orientation or alignment members  125 A protruding at regular intervals about a periphery (three are used herein and two are shown), and (b) permanent locking tab member  127 A having a hinged end springingly extending from motor housing  114  and ending in a cantilevered spring finger portion (as shown) for engaging and permanently fixing motor housing  114  into housing unit  102 , as will be discussed. 
   An air inlet channel or tube or passage  111  is internally positioned within a wall member of monolithic housing member  102 , and extends from a bottom air inlet opening  111 A to a top air exit opening  111 B aligned and in communication with air inlet  111 C after unit assembly. An air inlet screen member  112  is fixably positioned in air inlet  111 A and being preferably of a fine mesh construction prohibits water entry by physical blockage and capillary forces while simultaneously enabling a full flow of air to enter compressor unit  106 . 
   Brush housing  110  is formed as a fixable cap member and includes a central self-lubricating bearing or bushing member  105  allowing passage of electrical power to respective brushes  123 ,  123  (only one shown). While brush housing  110  is formed for receipt of wires, it will be recognized by those of skill in the art that alternative constructions to allow electrical connection to respective brushes  123  may be achieved without departing from the scope of the present invention. For example, an electrical connection to respective brushes  123 ,  123  may be achieved employing solid state copper electrical fingers (not shown) projecting from a bottom portion of brush housing  110  and engaging respective electric finger members (not shown) crimped on the end of respective electrical wires (not shown), all without departing from the scope and spirit of the present invention. 
   As depicted, brush housing  110  has a peripheral extending lip member  122 , having a thickness  126  and projecting outwardly sufficiently to engage the bottom surface of monolithic housing member  107  and to form a weather tight seal thereto. As an additional safety factor, extending lip member  122  may optionally include a sealing O-ring channel (not shown) and a flexible elastomeric O-ring  121  to prohibit water entry. An optional cut lip region  124  is shown such as to prohibit lip member  122  from blocking air access to air opening  111 A. It will be recognized, that alternative constructions may be envisioned without departing from the scope and spirit of the present invention, including those without a lip region  124  and with alternative sealing mechanisms, such as the use of liquid sealants and mechanical friction seals. 
   A pair of locking screws  120 ,  120  pass through brush housing member  110  to engage openings in motor housing  114  and engage and lock with threaded holes on an underside surface (not shown) internal to compressor pump member  109 , thereby fixedly securing brush housing member  110  into compressor unit  106 , sealing brush housing  110  to the bottom surface of monolithic compressor housing portion  107 , and drawing and urging compressor unit  106  fully into housing  102  to fully engage locking tabs  127 A in respective locking engagement openings  128 B (see  FIG. 3 ) formed in the rigid wall of monolithic housing member  107 , as will be discussed. 
   A particular advantage of the proposed construction is that locking tabs  127 A and corresponding locking grooves  128 A provide an initial stage of permanently fixing compressor member  106  in housing unit  102 . As an important secondary advantage it must be recognized that the present construction involving sealing brush housing  110  and locking screws  120  provides a second mechanism or system for securing and permanently fixing compressor unit  106  in position by actually urging a secure positioning and compressing or drawing-tightly of the compressor member  109  to the top side of housing unit  120  while simultaneously drawing brush pump housing  110  upwardly to the bottom side of housing unit  120  and sealing lip member  122  to the bottom surface thereby also ensuring complete installation of locking tabs/grooves  127 / 128  while improving weather resistance and preventing moisture entry. As a consequence, it will be recognized that the proposed invention adds multiple forms of permanently fixing that operate in distinctly different but complementary manners to achieve the desires of the proposed invention and provide a distinct advantage during manufacturing. 
   During assembly of the present preferred embodiment, it is envisioned that housing unit  102 , with monolithic housing member  107  is secured in position and a operator or machine grips a pre-assembled motor housing  114  and compressor  109  (fixed together by fixing fingers  115 ). The operator then orients compressor  109  so that air outlet fixture  113  is oriented to be fittingly received within air outlet receiving block  113 B and initially engages the bottom of motor housing  114  in the opening in monolithic housing member  107 . While not required for the invention, and as an additional benefit, the motor housing  114  shown includes a plurality of alignment members  125 A that mesh with a plurality of pre-formed alignment slots  125 B formed on an inner wall of the compressor opening to aid and secure alignment. 
   As will be appreciated from the figures, while only a single pair of alignment member  125 A and alignment slot  125 B may be employed, the present embodiment includes a plurality of the same arrayed about the opening in monolithic housing  107  for improved security and eased assembly. In this way, the present invention enable swift and secure alignment during an assembly and minimizes a risk of unintended damage by contacting air outlet fixture  113  with the top surface of monolithic housing  107 . It is note that such unintended contact is a common assembly problem with the related art represented by U.S. Pat. No. 7,038,576, and results in quality control losses during assembly. 
   As will be additionally appreciated from the figures, receiving openings  128 A are formed within the inner side wall of the receiving opening of monolithic housing member  107  at pre-determined intervals to receive respective spring engaging and fixing member fingers  127 A. With the above-noted aid to alignment, locating specific pairs of fingers  127 A/openings  128 A is eased and simplified because there is no need, and indeed no ability, to rotate motor housing  114  relative to monolithic housing  107  after initial alignment. It is respectfully noted, that the receiving opening in monolithic housing  107  is shaped to snuggly fit the outer perimeter surface of the assembled motor housing  114  and compressor pump member  109  so as to allow secure engagement with fingers/holes  127 A/ 127 A as a permanent fixing mechanism preventing the removal of motor housing  114  (and the compressor unit  106 ) following initial assembly. It is additionally noted, in  FIG. 4 , that an alternative fixing mechanism may be employed, wherein, projecting spring engaging fingers  127 B project from the inner side wall of the monolithic housing  107  and are lockingly received in respective engaging openings  128 B formed in the outer periphery of motor housing  114  as shown. In this way, the present invention envisions a plurality of single use locking mechanisms that enable an initial assembly between monolithic housing  107  and compressor unit  106  and that prevent the possibility of removal thereafter, thereby removing the risk of unintended separation. 
   As will be additionally noted from the Figures, an outer projecting rim of compressor member  109 , shown on a proximate level with air outlet fixture  113  is firmly fixed to the top surface of monolithic housing member  107 . 
   As a consequence, the present embodiment it is noted, that during an assembly, the sub-combination of motor housing  114  and compressor member  109  are pre-assembled and then aligned, inserted, and fixably and non-removably locked in position within monolithic housing such that the outer projecting of compressor member  109  seals the same to the top surface of monolithic housing member  107 . It is noted that any form of additional seal may be employed, such as an O-ring or sealing caulk, to improve the seal between the outer projecting rim and the monolithic housing member  107 . It is envisioned that where such an O-ring is employed for sealing, a complementary O-ring groove or opening may be additionally employed to secure the O-ring in position. Such an O-ring groove may be on the brush housing lip  122 , on the top or bottom of monolithic housing member  107 , and on the projecting rim of compressor member  109 , without departing from the scope and spirit of the present invention. 
   Following installation of the sub-combination, the sealing member (O-ring shown) is positioned on the outer locking flange of the brush housing member  110  and locking screws  120  are inserted and tightened, fully sealing brush housing member  110  to compressor unit  106  and serving to apply a sealing tension on opposing sides of monolithic housing member  107  to improve unit reliability and manufacturing quality by preventing vibratory separation, temperature change damage, and the other detriments causing concern in the related art. 
   While the present embodiments contemplate the use of opposing spring fingers and receiving openings for allowing a form of single-use locking engagement during insertion, nothing herein shall so limit the invention. Those of skill in the art will appreciate that alternative locking mechanisms, assemblies, or elements may be employed without departing from the spirit and scope of the present invention. For example, permanently fixing compressor unit  106  in monolithic housing member  107  may be achieved additionally by the use of (a) locking high-durability adhesives, (b) thermal welding of plastic portions, (c) threaded-use-failure members (that thread in to a threaded path and lock in-place), (d) the use of pivot-locking members much as swing or pivot arms within either monolithic housing member  107 /motor housing  114  which engage after insertion to fixably position compressor unit  106 , and (e) other cam or key-way type engagements where a cam or key member are inserted between the monolithic housing unit  107  wall and motor housing  114 , since all such adaptive fixing mechanisms are known to those of skill in related arts and may be adapted as required to fulfill this goal. 
   Referring specifically now to  FIGS. 3 and 4 , alternative forms of the mounting bracket are shown, this time extending from monolithic housing member  107  as mounting members or blocks  117 A (on a top side), and optionally as a pair with a block  117 B at a bottom portion. As will be appreciated by those of skill in the art, the present invention repositions the housing blocks to the much stronger housing unit member  102  generally, and extends multiple mounting points to prohibit breakage due to the excessive vibration from compressor unit  106 . 
   While the present embodiment provides such mounting members or blocks  117 A,  117 B, it is additionally envisioned that alternative mounting systems may be employed without departing from the scope and spirit of the present invention. To this end, the present invention contemplates the use of magnetic, adhesive, and buckle and strap-type mounting systems. Regarding magnetic mounting system, it is envisioned that monolithic housing unit  102  may be readily molded and formed to receive a flush-mounted inset magnet or a series of flush-mounted or other magnetic members on a rear-attachment surface thereof. Employing such a magnetic mounting system it is envisioned that unit  100  may be readily positioned and secured in place on a magnetic or paramagnetic surface, such as a mounting wall within an automotive engine compartment. Regarding an adhesive mounting system, it is envisioned that, similarly to the magnetic mounting system, the molded monolithic block  102  be formed with planar faces on a rear or side surface thereof such that a high temperature or thermal welding adhesive may readily permanently fix unit  102  to any selected mounting surface. In combination with any of the above mounting systems, or alone, a buckle and strap-type mounting system is envisioned wherein rigid strap ridges and built in strap mounting arms are formed permanently in the monolithic housing member  102 , thereby allowing unit  100  to be strapped and fixed to a bar, beam, flat surface, or other structure element so as to prevent unintended removal. 
   As an additional benefit of the present invention, it is envisioned that horn openings  104 A,  104 B may be additionally made weather resistant by the use of Gortex type flexible shutters sealing each opening from moisture and dirt incursion so as to prevent the horn&#39;s premature failure in a wet or dirty operating environments while at the same time allowing the horn to produce the regular powerful tonal sound (limited if any decrease in sound performance). Such a shutter may be viewed as a single sealing piece of flexible material sealed over the opening but allowing vibration passage, a series of draping folds of similar material that drape closed under the force of gravity when not in use and spread open to allow sound release during a use, or a single draping fold on a hinged arm allowing only one-way sound exit while preventing inward entry of water and debris to the horn&#39;s sound chambers. Those of skill in the art will also recognize that such a similar piece of sealing substantially waterproof or water resistant material may be provided for air intake opening  111 A or  111 C to prevent related damage to compressor unit  106 . In all, those of skill in the art of product design will recognize that the use of such systems will virtually render the entire horn as waterproof, and certainly water proof for periodic splashes or immersion due to splashing when installed in an automobile, on a motorcycle, on a boat, or other vehicle. 
   Referring now to  FIG. 5 , an alternative embodiment of a monolithic electropneumatic sound generator unit  200  is noted, and comprises a monolithic housing block member  202  for receiving a partially assembled compressor unit  206 , as shown. 
   As noted from examining the figure, the entire acoustic tonal generator is, as was noted above, internal to monolithic housing block member  202  and operates via received compressed air from compressed air outlet fixture  213  (when inserted into protective air outlet receiving block  213 B) through respective internal tonal chambers passed diaphragm air supply ports  216 ,  216  (only one shown) and respective diaphragm units  203 ,  203  (only one shown) to generate sound which then is conducted via the remainder portions of respective internal tonal chambers to respective horn openings  204 A,  204 B for exit to the atmosphere. It is noted that constructions for the internal acoustic tonal passageway internal to the monolithic block are well known to the art and are generically represented by U.S. Pat. No. 7,038,576, the entire contents of which are again herein incorporated by reference, and it is only the external appearance of monolithic housing member  202  which is improved according to the present invention. 
   As noted earlier, compressor unit  206  includes a metallic motor housing portion  214  that is fixed to compressor member  209  as a first installation member or assembly, and is later assembled with a bottom brush housing member  210 , as will be discussed for permanently mounting into monolithic housing block member  202 . 
   As will be noted, a protective fixing skirt  220 A extends upwardly from the top surface of monolithic housing block member  202  and is shaped to fixably receive the first installation member as shown. A plurality of outer locking openings (shown but not numbered) in fixing skirt  202 A receive respective fixing bolts  220 A which engage and fixably seal with threaded openings in the top extending flange from compressor member  209  (as shown). In this manner, during assembly the first installation member or assembly is oriented to align air intake opening  211 B with an internal air channel outlet (not shown which extends from an external air intake opening  211 A protected by a protective screening member  212 ), and to align air outlet fixture  213  with air outlet receiving block portion  213 B. The installation member or assembly is then inserted into monolithic housing member  202  (as shown). 
   At this point either fixing members, the fixing bolts  220 A are inserted and fixed into the outer flange of compressor member  209  to fix the member in place, and/or additional locking members are employed (such as the locking tabs/openings noted in the earlier embodiment), to permanently fix the first installation member of compressor  206  in position. It shall be recognized, that while the present embodiment discloses only one fixing option (fixing bolts  220 A), that alternative and different fixing mechanisms may be used to permanently retain the first installation member or assembly (compressor member  209  and motor housing  214 ), and prevent it&#39;s removal following such assembly without departing from the spirit and scope of the present invention. 
   Thereafter, brush housing member  210 , having respective brushes  223  and bearing member  105  is positioned in a bottom of the receiving opening in monolithic housing member  202 , and permanent locking tabs (not shown) are lockingly inserted in respective receiving slots in the bottom side of housing member  202 . Thereafter, a bottom sealing cap member  225  having a respective outer flange and periphery mounting portions  224  is positioned, sealing O-ring member  221  is also positioned in O-ring groove  224 A, and respective locking bolt members  220  are inserted and locked in place fixing bottom sealing cap member  225  in position. As noted in the figure, a bearing pocket  105 ′, or bearing seal,  105 ′ enables the rotational end of the axle of motor housing  214  to extend through (if optionally needed) bearing  105  and still be covered by cap member  225  for a weather resistant seal (for example pocket or seal  105 ′ may be formed as a concave receiver retaining the pivoting end of the motor axle. As a consequence of this construction, it will be recognized that the present proposed assembly  220  is formed to receive and permanently fix compressor unit  206  in position following such assembly, and to prevent removal by a variety of mechanisms. 
   It will be recognized, that sealing O-ring member  221  and O-ring groove  224 A represent only one of a plurality of ways of sealing and protecting brush housing member  210  from weather encroachment. It will also be appreciated, that alternative constructions may seal bearing  105  in respective housing  210 , and also that cap member  225  may be replace with an alternative construction that allows a sealed electrical connection to the brushes without departing from the scope and spirit of the present invention. Such sealed electrical connections are known to those of skill in the consumer electronic arts, and may optionally include extending contact blades of copper that receive external electrical connection through cap  225 . Consequently, while power supply openings  105  may be readily sealed in ways known to those of skill in the art, other sealing designs shall be considered to be within the scope of the present disclosure. 
   Additionally, it is envisioned that a top compressor member sealing system (not shown) may be employed to provide a weather resistant cover (not shown) to the top of compressor member  209  following installation. Such a weather resistant cover may be formed with an expanding top flange and O-ring assembly (not shown), an external rubber cap may be sealed about skirt member  202 A, or a sealing and fixing epoxy may be poured within and over skirt member  202 A to both seal and fix the first assembly member of compressor assembly  206  in place. 
   It will also be appreciated by those of skill in the art that the present assembly overcomes at least one of the detriments noted in the related art and provides a rigid and secure mounting between the acoustic generation portion of the electropneumatic horn assembly and the compressor portion, thereby improving reliability. To this aid, attachment flanges  217  extend from portions of monolithic housing block  202  (one is shown) to enable easy fixing in place. Such attachment flanges  217  may be readily positioned elsewhere on monolithic housing, or replaced with any of the other mounting constructions noted herein, without departing from the spirit and scope of the present invention. 
   As noted earlier, the present embodiment enables sealing of the compressor unit  206  assembly openings on the top and bottom portions of the monolithic housing assembly  202 . As an additional benefit sealing screen  212  resists water and debris uptake while allowing air-passage. Similarly, the present embodiment of the electropneumatic horn assembly  200  may include the other optional sealing matters discussed above without departing from the scope and spirit of the present invention. For example, sealing Gortex shutters may provide one-way exit flow from horn openings  204 A,  204 B, sealing diaphragms may cover the openings, or other water and debris resistant covers may seal horn openings without departing from the scope and spirit of the present invention. In this manner, those of skill in the art will recognize that alternative and adaptive constructions may render the present embodiment substantially weather resistant and allow for adaptive installation in weather-exposure environments as an improvement of the related art. 
   Referring additionally now to  FIGS. 6 ,  6 A, and  6 B a third electropneumatic horn unit  300  includes a divided rigid housing unit member  102 ′ having a divided monolithic compressor housing region  307 A,  307 B, as shown, and an internally formed dual tonal acoustic ducting system (not shown). The dual tonal acoustic ducting system is similar to that shown in U.S. Pat. No. 7,038,576, and the entire contents of &#39;576 are herein again enclosed again by reference. The dual tone acoustic ducting system receives compressed air exiting a compressed air outlet  213 A of an air outlet fixture  213  from a compressor unit  306  (as will be discussed), passes the same via diaphragm members  103 ,  103  (only one shown) through respective diaphragm air supply portals  316  so as to activate the same as sound generators. The sound so generated passes through the dual tone ducting system to exist via respective horn openings  104 A,  104 B. As will be additionally discussed the tone or sound generation functions of the proposed embodiment are related to those noted in the incorporated &#39;576 patent. 
   As will be noted from study of the renderings, compressor unit  306  having a bottom positioned brush housing member  126 ′ and an opposing top sided compressor member  309  is completely surrounded by the monolithic body structure of housing unit  102 ′ in the manner depicted. As was discussed in the earlier embodiments, a rear suspending bracket (not shown) is rearwardly projected from compressor member  309  in a manner familiar to those of skill in the art, although substantial improvements of this construction are noted in  FIGS. 3 ,  4 , and  5 , as will be later discussed to secure horn unit  300  to a desired position following assembly. 
   As will be particularly noted here, housing unit  102 ′ and particularly compressor housing portion  307 , containing portions  307 A and  307 B are initially separable but include pairs of opposing bonding walls  330 ,  330  which following assembly as noted are thermally welded to each other to permanently and fixably bond portions  307 A,  307 B in an inseparable manner. Also on opposing bonding walls  330 ,  330  are a respective series of alignment systems  340 , as shown in  FIGS. 6 ,  6 A, and  6 B. Alignment systems  340  may optionally include a series of extending pins and holes, respectably  341 ,  342 , engagement spring clips  343  and slots (only spring clips shown in  FIG. 6A , and alignment and engagement slip ways  344  engaging opposing alignment pins (not shown) on an opposing bonding wall  330 . 
   As will be readily apparent to one of skill in the art having reviewed the present disclosure, during an assembly, compressor  306  is placed within the first ark shape of housing portion  307 A, as shown and aligned employing a series of alignment protuberances  325  on the compressor outer wall (as shown). Thereafter, the opposing arc portion of housing portion  307 B is positioned and aligned employing any of the alignment systems  340  shown, or any of those understood to those of skill in the art having appreciated the present disclosure, so that opposing bonding walls  330 ,  330  are in contact along their bonding surfaces. Thereafter, a thermal or radiant bonding is applied along the ranges of bonding walls  330 ,  330  so as to permanently fix them in position and render compressor unit  306  completely fixed in position within housing  102 ′. Thereafter, as discussed above, bottom brush housing member  126 ′ is fixably positioned to complete assembly and provide a second locking system to fixably retain compressor unit  306 . 
   A fourth embodiment of electropneumatic horn unit  400  is characterized by the compressor unit part  406  being mounted fixedly permanently to the monolithic mounting housing, this embodiment having enhanced operational reliability which contributes to an especially longer service life. 
   Referring to  FIGS. 7 and 8 , horn unit  400  includes a monolithic housing  402  comprised of an assembly  402  having first and second housing portions  401 A,  401 B. These two portions includes housing parts  407 A,  407 B and  407 C—seen in  FIG. 8  before assembly together. In the assembly as depicted in  FIG. 7 , the parti-circular housing parts  407 A and  407 B which comprise the housing first portion, are joined in girding encirclement of compressor unit  406 , being permanently joinable together along opposite end edges of each housing part. Housing part  407 C serves for mounting diaphragm  403  and constitutes the second housing portion  401 B. Housing part  407 C is permanently affixed to housing part  407 B. A horn opening  404  is provided at a front face of housing part  407 C. In the assembly, housing parts  407 A,  407 B include an opening which defines a cylindraceous reception space for receiving the cylindraceous outer periphery configured electric compressor unit  406 . A block  417  for mounting the assembly in use, such as on a vehicle firewall, is carried by and extends outwardly from an upper part of the compressor unit  406 . 
   Referring to  FIGS. 8 and 9 , compressor unit  406  includes a top side part  409  which houses compressor pump member  406 A, air intake to which is taken from outside environment through air inlet passage  415  and passes into the pump member through an air inlet  411  thereof, pressurized air outletting the pump member by way of outlet  430 . Outlet  430  communicates with a first end of tubular member  424  that is permanently affixed in both the structure of the pump member  406 A and in structure segment  407 E of housing part  407 C. An opposite end of the tubular member communicates with an entry opening  488  leading to at least one acoustic chamber in the housing second portion  401 B. 
   Tubular member  424  has ring like or similar protuberant like structure  444  encircling the outer periphery thereof, this to enable the tubular member to function as an air seal obviating any leakage in and around the region where pressurized air leaves the compressor pump and enters the sound generating structure carried in housing part  407 C. The tubular member  424  is fixedly, permanently mounted to structures  406 A and  407 B. Such fixing can be by a number of ways as, for example, with thermal or radiant bounding, press fitment, as well as others of affixing means effective to the purpose at hand of permanently affixing the tubular member in the assembly. 
   Carried within housing parts  407 A and  407 B are fins  428  disposed longitudinally of the respective housing parts and which extend downwardly from the flange pieces  432 A at the tops of these housing parts  407 A,  407 B. The fins  428  at lower ends thereof have joinder to lower flanges pieces  432 B. Inner edges of flange pieces  432 A,  432 B terminate slightly radially outwardly of the inner edges of the fins  428  so that when the assembly is subjected to final affixing tightening, the fins have a slight engagement with the outside of motor housing  414 . 
   Extending downwardly from compressor unit top side part  409  is a motor housing  414  which encircles and is affixed to drive motor structure (not shown) employed to power the compressor pump unit  406 A. Motor housing  414  is provided with an opening  438  employed in cooperation with an alignment member  426  to effect necessary and proper registering of longitudinal alignment of the compressor unit with and within the housing structure of the assembled together housing parts  407 A,  407 B and  407 C. It is noted that the inner structure envelope of these housing parts present a cylindraceous receiving profile in correspondence to the like outer configured profile of the compressor unit  406  to be encirclingly received therein. As best seen in  FIG. 9 , the alignment member  426  is an enlarged cylinder stepped down to smaller cylinder dimension at the front end thereof. The large body part is received in a companion configured pocket part  442  of housing part segment  407 E. The alignment member is permanently affixed in the pocket and in the assembled structure, its stepped down front end passes thru opening  438  in the motor housing, this mating assuring that proper housing compressor unit alignment is achieved. 
   The motor housing  414  compressor unit  406  will be permanently affixed to other structure of the compressor pump unit  406  A other drive motor portions as needed. For that purpose, the locking means such as spring means  115 ,  127 A seen in  FIG. 3  or such means  215  in  FIG. 5  can be employed. Also, alignment member  428  will be affixed in pocket part  442  of housing segment  407 E. Similarly, the tubular member  424  is affixed to the structure of the compressor pump unit  406 A. The compressor unit is then juxtaposed with the open face side of housing part segment  407 B to align and insert these two members in companion receptive parts of the segment  407 E. In effecting this, the tubular member  424  has been inserted in the compressor pump unit in communication with air outlet  430 , and the alignment member  426  is passed thru opening  430  in motor housing  414 , and housing part  407 B partly girds the compressor unit  406 . The housing part  407 A is then girded about the still ungirded portion of the compressor unit  406 . In effecting this girding encirclement of the compressor unit, longitudinal flange extensions  450  on housing part  407 A with engage in companion right angle slots  452  on the housing part  407 B. The extensions  450 -slots  452  structure having juxtaposed engagement are permanently affixed to each other by thermal or radiant bonding, electric welding, adhesive or other suitable affixing means. 
   In completing the assembly, additional affixing is made as depicted in  FIG. 10 . Referring to that Figure and with, A bottom seal cap  425  similar to the seal cap  225  depicted in  FIG. 5  is employed to close off the bottom of the compressor unit  406  and prevents entry of debris or water into the unit  400 . The seal cap  425  is affixed to the compressor unit with a pair of elongated bolts  420  which pass up thru bottom seal cap  425 , a bolt lower end having a bolt head  455  which stops against structure of the seal cap. An opposite bolt end is threaded as at  456  and this threaded portion is received in a blind threaded bore  457  formed in the structure of the compressor pump unit  406 A, the bolts being drawn up tight in the compressor unit structure. In this condition, the lower edge  460  of motor housing  414  sits supported on an encircling ledge face  462  form on the seal cap. In stead of a ledge surface, the seal cap can be formed with a radially outwardly directed encircling skirt or flange (not shown in  FIGS. 9 and 10 ) on which the motor housing lower edge  460  would sit. 
   In accordance with the invention, the components of the horn unit  406 , are permanently affixed together and it is not possible to remove the compressor unit  406  from the housing structure. This is a result of a number of deterring construction features. Air seal tube  424  and alignment member  426  are affixed in structure of the monolithic housing and the compressor unit  406  in a manner that prevents movement therebetween, as well as preventing entry of debris and water into the unit. 
   In the claims, means- or step-plus-function clauses are intended to cover the structures described or suggested herein as performing the recited function and not only structural equivalents but also equivalent structures. Thus, for example, although a nail, a screw, and a bolt may not be structural equivalents in that a nail relies on friction between a wooden part and a cylindrical surface, a screw&#39;s helical surface positively engages the wooden part, and a bolt&#39;s head and nut compress opposite sides of a wooden part, in the environment of fastening wooden parts, a nail, a screw, and a bolt may be readily understood by those skilled in the art as equivalent structures. 
   Having described at least one of the preferred embodiments of the present invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes, modifications, and adaptations may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.