US1110275A - Mechanical horn. - Google Patents

Description

E. J. WILLIS.

MECHANICAL HORN.

APPLICATION FILED 2mm, 1912.

Patented Sept. 8, 1914;-

UNITED STATES PATENT OFFICE.

ERNEST J'. WILLIS, OF NEW YORK, N. Y., ASSIGNOR, BY MESNE ASSIGNMENTS, TO

LOVELL-MQCONNELL MANUFACTURING COMPANY, A CORPORATION OF DELA- WARE.

MECHANICAL HORN.

To all whom it may concern:

Be it known that I, ERNES" J. IVILLIS, a subject of the King of the United Kingdom of Great Britain and Ireland, residing at the borough of Manhattan, in the city, county, and State of New York, have invented certain new and useful Improvements in Mechanical Horns, of which the following is a specification, reference being had therein to the accompanying drawings, which form a part thereof.

My invention relates to mechanical horns of that type in which a striker member preferably'in the form of a rotary cam imparts vibrations to a diaphragm to generate the sound waves.

In'carrying out my invention, I transmit the impacts, blows or forced thrusts from the rotor to the diaphragm by means of an interposed lever member and as an important feature of my invention, I make that portion of said member between the point'of its engagement with the striker member and the end engaging the diaphragm, stiffened or reinforced so as to avoid any loss of the power applied thereto through elasticity at this point.

I preferably employ a small electrical motor as the source of power, and one feature of my invention involves the mounting'of this motor so as to avoid any loss of 'alinement of the shaft carrying the striker'memher, while admitting of the accurate adj ust ment of said member in assembling the de vice. And a still further object is to provide a horn of this character which will be simple in design and inexpensive to produce. Referring to the drawings: Figure 1 is a longitudinal section of a horn embodying my invention; Fig. 2 is a section on the line 2-2 of Fig. 1; Figs. 3, 4 and 5 are similar to Fig. 2, showing modified forms of impact members.

Like letters refer to like parts throughout the several views.

In the embodiment of my invention shown in the drawings, a/indicates a front diaphragm casing section provided with an opening a communicating with an amplitier 7). Secured to the casing section a is a rear diaphragm casing section 0 having thereon a plurality of lugs or flanges (Z e adapted to support the motor f. The lugs Specification of Letters Patent.

Application filed February 6, 1912.

Patented Sept. 8, 1914.

Serial No. 675,836.

' will be clamped in place between these two detachable sections. The casing a has a cylindrical peripheral flange a adapted to inclose the edge of the diaphragm k and secure it and the gaskets h and k in position relative to said casing. The diaphragm it as shown presents an uninterrupted plane, no stud being used centrally thereof, thus preserving the entire strength of the diaphragm and avoiding the weakening thereof in a manner to impart thereto a tendency to cup; Inclesing the motor f is a cupshaped housing 2' carrying the electrical con ta-cts which are adapted to be automatically coupled to the motor upon the application of same to the casing. This housing is secured by means of screws is to the section 0.

Carried by the shaft Z of the motor 7 is a rotor or cam constituting a striker member preferably formed of a sheet metal plate m having thereon a plurality of contact surfaces or cam faces m, these surfaces being raised above the plane of said plate and being spaced apart sufiiciently to afford ample clearance between Succeeding contacts to permit such an interval of time between the successive blows imparted by said striker member as will allow the diaphragm to havethe full amount of reflex action between the impacts flexing same. The height of the contacts or cam faces m. is greater than the amount of displacement of the diaphragm upon the reflex action thereof. Instead of [so mounting the rotor that the cam faces thereon will directly engage with the diaphragm itself, I mount between the rotor m and the diaphragm h a flxible'diaphragm vibrating member n adapted to be forced by the impact from the cam faces of the rotor and en gage with the diaphragm to forcibly dis- (Z e are provided with elongated slots to 1 place the latter, upon receiving each imios pact and thus set said diaphragm into rapid vibration to develop sound waves of the desired frequency and intensity. In the preferred form, this diaphragm vibrating member is in the form of a. flat strip of highly tempered spring metal extending radially of the diaphragm with its outer end secured adjacent to the periphery of the diaphragm and the inner end terminating adjacent to the center of the diaphragm.

The shaft Z projects substantially axially of the diaphragm, thus positionin the contacts m concentrically of said diaphragm and permitting them to engage the diaphragm vibrating member intermediate the point of support thereof and the polnt thereof adapted to engage the diaphragm, thus securing a leverage with a slightly increased quantity of movement of said memher at its point of engagement with the diaphragm over that of the point of-engagement with the said striker member. I may secure an increase in the frequency of the flexures of the diaphragm with each rotation of said striker member by causing said striker member to engage the member or members alternately upon opposite sides of the center of said diaphragm. This may be done by giving the plate m an odd number of contacts m so that these contacts do not simultaneously deliver blows at dia-n metrically opposite points. WVhile I prefer to increase the frequency of the'impulses imparted to the diaphragm in the manner referred to, as tending to secure a greater volume of sound without overloading the motor or requiring too strong a current, a member having a single point of contact and adapted to be engaged by the said contacts m, may be utilized if desired, and I have illustrated such a member in the modification of the invention shown in Fig. 4,

In the form shown in Figs. 1 and2, the vibrations are imparted to the diaphragm from the rotor by two separate strips n in alinement with each other, and each extending from the periphery to the center of the diaphragm. At their outer ends they may beriveted to the casing section 0 and the inner ends thereof may be spaced :1 very slight distance apart. Formed up from these strips at the free end thereof, are studs n adapted to having forcing engagement with the diaphragm and at the same time permit the other portions of said member to be spaced away from the diaphragm sufficiently to aviod interference therewith. In the .specific embodiment illustrated, the studs 11 when thus assembled, are spaced away from the diaphragm in order. to secure higher efiiciency in the operation of the device. Each said stud also has formed up therein, but upon the face oppositeto the stud n, a contact 02 positioned within the operative range of the contacts m, said contacts n being spaced away from the studs 12. To avoid any possibility of the flexure of the member between the contact n and the stud m, I form in said strip a fillet or bead, extending from said stud to said contact, said fillet being a mere extension of the contact 11 This fillet or bead stiffens the member between the point of engagement of the striker member therewith and the stud 02. By this construction, I am not only enabled to construct the diaphragm vibrating member and the studs and contacts thereon of a single strip of metal, but also to provide a diaphragm vibrating member which is normally spaced away from the diaphragm throughout its entire length to avoid interference in the diaphragm while securing to it that high degree of flexibility which is desirable in a high frequency, low power mechanical horn of the character herein described. By duplicating the members a, I increase the frequency of the fiexures of the diaphragm without necessitating more than a duplication of the member alone. To facilitate the adjustment of the motor f within the lugs d e, I secure the motor in place by means of the screws 8, the heads of which bear upon the clamp plate 1' bearing upon the lug e.

In the modification shown in Fig. 3, the construction and mode of operation are substantially identical with that of the preferred form, with the exception however, that the member 0 instead of being'made in two sections, as shown in the preferred form, is made of one continuousstrip of metal bridging the diaphragm and having a central stud 0 formed therein and projecting toward the diaphragm, and two fillets 0 extending from said stud and terminating in contacts adapted to be engaged by the rotor m.

In the modification shown in Fig. 4, the construction is substantially identical with that shown in Fig. 3, with the exception that but a single fillet 0 is utilized, thus reducing the frequency of the vibrations with each rotation of the striker member.

In both forms of the invention shown in Figs. 3 .and 4, the strip is stretched taut across the diaphragm, and the opposite ends thereof are riveted to the frame 0. Also in both of these forms, the interposed member is spaced away from the diaphragm, including the stud 0 thereon.

In the modification shown in Fig. 5, of the. drawings, I provide two radially extending members p g, which converge toward the center of the diaphragm, the outer ends of and the inner ends thereof being cupped as shown at p g to form a stud for engagement with the diaphragm. Each said strip p g is provided with a fillet p 9 extending from the cupped portion p 9' thereof, for

these members being riveted to the frame 0 of the frequency of the vibrations imparted b ysaid member to the diaphragm.

The operation of the herein described device is substantially as follows: With the closing of the circuit to the motor f, the shaft Z and the striker member m thereon will be rapidly rotated in a fixed plane, and the contacts 112/ thereon will in sequence engage the oppositely disposed contacts 11?, 0 p or 9 upon the interposedmember n 0 p or g, flexing this member between said contact and the point or points of support of said member, and bring the stud n 0 p or 9 into engagement with, and cause it to flex, the diaphragm h, at a point substantially centrally thereof, or slightly to one side of its center. The space between the contact-syn will afford suflicient lead to the striker member to cause the impact thereof with the 'contact 12, 0 p or to be in the nature of a sharp blow, thus causing a rapid vibration of the diaphragm. The sections n, 0, p, 9, between the contact 71? 0 p or g and the Stud 91., 0,';0' or 9, being reinforced or stiffened, sufficient rigidity is im parted to this point of the member to insure absolute rigidity thereof and thus cause the entire force of the impact of the striker member m upon the saidmember to be trans ferred to the diaphragm. I have found in actual practice that a most effective signal can'be secured by the construction herein described, through a flexture of the diaphragm of a sixty-fourth of an inch or less, the low resistance due to the short interval of engagement of the contacts n 0 g and m. reducing the amperage required to run the motor to a very low point. The space between the successive contacts m, coupled with the low degree of fiexure of the dia phrag'm, avoids a retardation of the diaphragm, and permits it upon the reflex action thereof, to pass its normal plane. By the multiplication of impacts a 0 p or 9 the frequency of the impulses imparted to the diaphragm may be increased and may be the multiple of the number of contacts 7m, and the number of opposed contacts 71 or 9 In the preferred form of the invention, each contact m upon the striker m engages in sequency the contacts n upon the plurality of flexible interposed impact members n, each flexible impart member moving entirely independently of the other and acting in the same manner upon the diaphragm.

In the form of the invention -shown in Figs..3 and 4, the bridge-like structure of the flexible member is desirable as insuring 'said impact member ad acent to its point of a quick return of this member to normal.

In-assemblingthe horn and attuning it, the screws 3 are released slightly so as to permit the entire motor to slide between the lugs d and 6 toward or from the diaphragm, and when. the desired tone has been developed, said screws may be set upon the clamp plate 1' to lock the motor in this position. The location of the said lugs d and 6 will hold the motor perfectly true so as to secure the desired alinement of the motor shaft.

It is not my intention to limit the invention to the precise details of construction shown in the accompanying drawings, it being apparent that such may be varied without departing from the spirit and scope of the invention.

Having described my invention, what I claim as new and desire to have protected by Letters Patent, is

1. A. mechanical horn, embodying therein a flexible diaphragm, a flexible impact member supported in a fixed position relative to, and, adapted to be forced into engagement with and to flex, said diaphragm, a contact carried by said impact member adjacent to its point of engagement with the diaphragm, a rotary striker member adapted to engage said contact and force said impact member into engagement with said diaphragm, and means actuating said striker member, said impact tween said contact and the point thereof engaging the diaphragm, whereby the full force of the striker member is imparted to the diaphragm through saidistifi'ened portion., w

Amechanical horn, embodying therein a flexible diaphragm, a flexible impact member supported in a fixed position relative to, and adapted to be forced into engagement with, and to flex, said diaphragm, a contact carried by said impact member adjacent to its point of engagement with the diaphragm, a rotary striker member having thereon a plurality or sequence of contacts spaced apart one from the other whereby said'contact carried by said impact member may pass between said contacts upon said striker member, and the reflex action of said diaphragm is permitted, and means actuating said striker member, said impact member being stiffened. or reinforced" between said contact and the point thereof engaging the diaphragm, whereby the full force of the striker member is imparted to the diaphragm through said stiffened portion.

3. A. mechanical horn, embodying therein a flexible diaphragm presenting a plane surface adapted to be engaged by an impact member, a flexible impact member supported in a fixed position relative" to, and adapted to be forced into engagement with and to flex, said diaphragm, a contact carried by .member being stiffened or reinforced beactuating said striker member, said impactmember being stiffened or reinforced between sanl contact and the point thereof engaging the diaphragm, whereby the full force of the striker member is imparted to the diaphragm through the said stifiened portion.

4-. A mechanical horn, embodying therein a flexible diaphragm, a rotary striker member, a flexible impact member between said striker member and said diaphragm and adapted to be forced into engagement with said diaphragm by said striker member, said striker member acting" upon said impact member eccentrica-lly of said diaphragm, and said impact member between the point of engagement of the striker member therewith, and the point of its engagement with the diaphragm, being stifiened or reinforced, whereby the full force of the blow delivered by said striker member is imparted to the diaphragm. j

A mechanical horn embodying therein a diaphragm, a cam rotor disposed adjacent thereto and means for effecting vibration of said diaphragm upon the rotation of said rotor, said means including a flexible mem: her having operative engagement with the diaphragm at the center of the latter and one end supported adjacent the periphery of the diaphragm, and a contact carried by said member adjacent to its point of engagement with the diaphragm, said member bein stiftoned or. reinforced between said contadt and the point thereof engaging the diaphragm. 6. Av mechanical horn embodying therein a diaphragm, a cam rotor disposed adjacent thereto and means for effecting vibration ofsaid diaphragm upon the rotation of said rotor, said means including a sheet metal strip extending radially of the diaphragm substantially parallel thereto and having operative engagement with the diaphragm at the central portion of the latter, said memher having a contact adapted to be engaged bv said cam rotor, and having a'stifiening or reinforcing element between said contact and the point of said member engaging the diaphragm, i

T. A mechanical horn embodying therein a diaphragm, a flexible elongated member extending substantially radially and having thereto and rotatable about an axis substantially at right angles to said diaphragm at the center of the latter, and means for effeeling vibration of said diaphragm u on the rotation of said cam, said means inc uding a sheet metal strip extending radially of the diaphragm, substantially parallel thereto,'and having operative engagement with the diaphragm at the central portion of the latter, said member having a contact adapted to be engaged by said cam, and spaced along the length of said member, from the pointof said member engaging the diaphragm, and said member having a stiffening or reinforcing element extending lengthwise thereof between said contact and the point or said member engaging the diaphragm. v t

.9. A signaling device including a diaphragm, an annular member having its peripheral portion substantially rigid with the periphery of said diaphragm and having a large central aperture, an electric motor projecting into said aperture and having means for vibrating said diaphragm, said member having a plurality of spaced flanges integral therewith and engaging with the peripheral surface of said motor, a clamping plate upon the outer surface of one of said flanges and means for securing said plate rigid with said motor and with said last mentioned flange therebetween for retaining the motor in position and permitting of its bodily longitudinal adjustment toward and from the diaphragm.

.ln witness whereof, I have hereunto affixed my signature in the presence of two subscribing witnesses, this 2nd day of February, 1912.

ERNEST J. WILLIS.

' Witnesses: F. T. WENTWORTH, EUGENE VVENING.

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