Патент USA US2113055код для вставки
April 5, 1938. H_ MGCURDY FREQUENCY AND WAVE LENGTH SOUND CHANGER Filed May 17, 1937 2,113,055 2,113,055 Patented Apr. 5, 1938 UNITED STATES PATENT OFFICE 2,113,055 FREQUENCY AND WAVE LENGTH SOUND ‘ CHANGER Howard McC‘urdy, Walnut Park, Calif. Application May 17, 1937, Serial No. 143,088 1 Claim. (Cl. 181—60) This invention is an apparatus for substan ‘tially changing the length and amplitude of sound waves.‘ It is an object of the invention to very mate 5 rially reduce or eliminate the objectionable wave impulses set up by operation of various machines, especially such as the more powerful pressure fluid operated motors which almost continuously discharge exhaust gases under high amplitude to 10 the atmosphere. . Particularly, an object is to substantially in stantly break a sound wave into lesser waves as to amplitude and length so that the objection or noise and vibration reactions to the wave will ll) be avoided. Further, an object is to provide a sound wave changer of utmost simplicity, of low cost relative to its given installation; of freedom from back pressure reactions; and which is devoid of labyrinthic characteristics and therefore will not choke up. - It is understood that the uses of the apparatus are very numerous and greatly varied, and it is not here intend-ed that the device is limited in respect to its utility. OO It is an object to provide a sound wave changer 1 which will function to break a sound wave into any suitable number of lesser waves which will impact the atmosphere is such a reduced manner as to be incapable of undesired noise and reaction vibrations. At the same time it is an object to provide for such a subdivision of a wave without the use of very objectionable, closed - type cushioning chambers and merely circuitous pas 5 03 sages offering frictional resistance to the flow of exhausting gases. The invention consists of certain advancements in this art as set forth in the ensuing disclosure and having, with the above, additional objects Ill) and advantages as hereinafter developed, and whose construction, combination and details of means and the manner of operation will be made manifest in the description of the annexed illus trative embodiment; it being understood that 45 modi?cations, variations and adaptations may be resorted‘ to within the scope, principle and spirit of the invention as it is more directly claimed in the appendage. Figure 1 is an axial, elevational section. Figure 2 is a cross-section on line 2—2 of Fig. 1. Figure 3 is a schematic diagram of the stream ?ow and subdivision in the device. In the adaptation of the Wave changer to an internal combustion motor the exhaust gases 55 therefrom pass through a conduit 2 which is ?xed 50 concentrically in an end head 3’ of a ?rst stage chamber or cylinder 3 of a diameter of greater dimension than that of the conduit 2 at its con nection with the head 3’ which is the intake of the chamber 3. The chamber 3 has a far end wall in the form of a flat annulus 4 against which is abutted a second stage chamber or cylinder 5 here shown as of less diameter than chamber 3 but larger than the concentric opening 4’ of the wall or partition 10 4 and which is here plainly shown as. materially smaller than the inlet opening 3" in the intake head 3’. Thus the wall 4 presents a very con siderable face area 4e, Fig. 2, across the projected bore of conduit 2 at the intake opening 3". This is clearly depicted in Fig. 3. The far end of the second stage chamber 5 is provided with an end wall in the. form of a flat annulus 3 having an axial opening 6’ materially smaller than the coaxial opening 4’ of wall It so that it presents a considerable annular face area 61’- concentric, in end view, of the face 4*at of the wall 4. The wall 6 is abutted by a third stage cham ber or cylinder 1 of substantially larger diameter 25 than the opening 6’ of wall 6; chamber 1 having an imperforate end closure 8. A protective balile 9 is, if desired, ?xed inwardly of the end closure 8. It is understood that the number of stage cham bers and their dimensions will be determined in 30 accordance with given wave of sound to be sub divided. Each chamber 3, 5 and l is provided with suit ably disposed exhaust ports H], which, if so de sired, according to the case, may be provided with external de?ectors l l of any desired type, having the supplemental function of further altering the character of wave force discharging at the ports it). These ports are preferably so disposed as to provide for radial expansion of the gases in their respective stage chambers; particularly the ar rested fractions of the gas stream stopped by the interposed barrier face areas 4a, 6a and 9. The rigidly, coaxially joined chambers 3, 5 and ‘l are preferably enclosed in a considerably larger collecting drum or shell 12 having an exhaust pipe l3 leading freely to an atmospheric dis charge or outlet so that no objectionable back pressure is set up against gas discharged at the vent ports ID of the multi-stage wave changer formed of the several chambers 3, 5 and 1. It is understood that the gases and propagated sound waves are not caused by the shell I2 to be con ?ned thereinand passed back to ?ow circuitously from one chamber to the other but are caused to 55 2 2,113,055 pass directly to atmosphere, unless passed to some heat exchange apparatus for utilization of the contained heat. Cl Referring now to Fig. 3, it will be seen that a stream of exhaust gas will pass from the conduit 2 axially into chamber 3 where a peripheral, an nular fraction of the cylindrical stream will abut the interposed annular area 4c of the transverse tions are outwardly, radially expanded in lag ging time steps and impact the atmosphere in ?rst stage wall 4. successive, weakened impulses. The arrested tubular stream 10 S1 will then expand into the larger cylinder 3 at the space V1 and discharge through the ports Ill of chamber 3. At the same instant a concentric tube S2 (or fraction) of the axially flowing gas stream has advanced to the stop area B11 of the wall 6 of second cylinder or chamber 5 and the arrested stream tube S2 expands; to the annular space V2 in chamber 5 and escapes at ports l0. Meantime the central stream fraction S3 axially ?ows through hole 6’ of wall 6 and abuts ba?le 9 and radially expands into annular space V‘. While the ?ow of a single sound wave of the propagating gas stream from chamber 3 to- cham bers 5 and 7 may be considered instantaneous yet the period is actually divided into a plural ity of lagging time steps. During the time lag of passage of a wave from chamber 3 to second chamber 5 a part of a given wave has been in tercepted by the barrier area 4a and has been discharged through expansion space V1 to the low (atmospheric) pressure in shell I2 and thence to the atmosphere. Immediately following this the concentric, tubular stream fraction or wave part S2 is arrested by the wall barrier area 6*‘ and is radially expanded through space V2 to the shell l2 and to atmosphere. Finally, the core or center stream fraction S3 is stopped by ba?le 9 and is radially expanded through space V3 and ports H] to the atmospheric shell l2. 40 gradually-seaping, uninterrupted stream of gas ?ow. On the contrary, there is a positive stop ping of numerous, contiguous, concentric frac Thus the full sound wave force is not thrown onto the atmosphere at one instant but is divided and discharged as time lagging fractions one after the other and their sound and vibration effects greatly choked. The device has no closed, cushion forming chambers; no continuous line of ?ow, direct or circuitous from end to end through which the wave propagating ?uid must pass, and has no tions of the wave forming stream by the axially spaced, concentrically presented barrier areas 4a, 5a and baf?e face 9. The stopped wave por What is claimed is: ' A sound wave sub-dividing device including an 1O exhaust shell, and a series of progressively stepped-down chambers in the shell, one end of the shell being closed by a head to which the near end of the largest chamber is abutted concentri cally of the shell, a gas conduit leading into said largest chamber through an axial in?ow opening which is materially smaller than the diameter of said chamber, a ?rst discal wall closing the back end of said chamber and having a ?rst con centric, gas outlet which is materially smaller than the said in?ow opening and said ?rst wall constituting a baffle in front of which an annu lar volume of incoming gas is arrested and is permitted to unobstructedly expand toward and for the full length of said largest chamber; a second expansion chamber whose forward end concentrically abuts said ?rst wall and is of materially larger diameter than the outlet in the ?rst wall so as to provide for free direct outward 30 expansion of gas coming through said wall, a sec ond discal wall closing the back end of the sec ond chamber and having a second, concentric gas outlet which is of materially smaller diameter than the ?rst wall outlet and said second wall - constituting a ba?ie in front of which the incom ing gas is arrested except at the second outlet and is permitted to expand unobstructedly to ward and for the full length of the second cham ber; and a third chamber concentrically abutting 40 the second wall and being of materially larger diameter than the second wall opening and form ing for its full length an unobstructed expansion space for the stream of gas incoming from the second wall opening; all of the said chambers 45 having outlets into the exhaust shell. HOWARD MCCURDY.