US2918894A

US2918894A - Mechanical apparatus for displaying electrical phenomena or the like

Info

Publication number: US2918894A
Application number: US767611A
Authority: US
Inventors: Edward R Jahns
Original assignee: Hoffman Electronics Corp
Current assignee: Hoffman Electronics Corp
Priority date: 1958-10-16
Filing date: 1958-10-16
Publication date: 1959-12-29
Anticipated expiration: 1976-12-29

Description

Dec. 29, 1959 E. R. JAHNS 2,918,894

MECHANICAL APPARATUS FOR DISPLAYING ELECTRICAL PHENOMENA OR THE LIKE Filed Oct. 16, 1958 2 Sheets-Sheet 1 DE Q QUSQLOQ!) Ill.

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Dec. 29, 1959 I JAHNS 2,918,894

v .MECHANICAL APPARATUS FOR DISPLAYING ELECTRICAL PHENOMENA OR THE LIKE Filed Oct. 16, 1958 2 Sheets-Sheet 2 T ,/52 I 1 55 /5 2a 48 [DWQQD 1Q JQA/A/S INVENTOR.

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MECHANICAL APPARATUS FOR DISPLAYING ELECTRICAL PHENOMENA OR THE LIKE Application October 16, 1958, Serial No. 767,611

2 Claims. (Cl. 116124.1)

This invention is related to mechanical apparatus for displaying electrical phenomena and, more particularly, to new and useful mechanical apparatus for stereophonic high-fidelity amplifying equipment for indicating visually to the operator the frequency response characteristics of two electrically separate but stereophonically related amplifiers, with particular reference to both the bass and treble response characteristics of each amplifier.

United States Letters Patent No. 2,841,110, entitled, Mechanical Apparatus for Displaying Electrical Phe nomena or the Like, was issued to the same inventor and assignee on July 1, 1958 for a similar device. However, the apparatus disclosed therein related only to the visual indication of frequency response characteristics of a single amplifier for high-fidelity equipment and could not be used to separately indicate both bass and treble response characteristics of two separate amplifiers.

There are certain problems involved in control of highfidelity equipment. Even with equipment having a single enclosure for the speaker system and a corresponding single amplifier system, the average person is unable to aurally distinguish bass and treble response characteristics to a suificient degree to assure proper adjustments of the amplifier system. This problem obviously is enhanced many fold in the case of stereophonic systems not only because of the simple multiplication of speaker and amplifier systems but also because of the necessarily separated locations of the speakers. For convenience of both operation and manufacture, the bass and treble controls should be generally located in physical association with only one of the speaker systems. Thus, not only does the operator stand closer to one speaker system than he does to another so that he hears the sound from the separated speakers with unequal volume, but also he is not located within the allowable spatial range for proper reception of stereophonic reproductions and hence cannot make correct bass and treble adjustments in accordance with his aural responses alone. Further, stereophonic reproduction often requires bass boost and treble roll off adjustments for one amplifier-speaker system and bass boll off and treble boost adjustments for another amplifier-speaker system; such adjustments are extremely difiicult to accomplish when reliance is placed solely upon aural perception.

Therefore, it is an object of the present invention to provide simple and inexpensive mechanical means, mechanically actuatable, for visually simulating selected electrical phenomena such as both bass and treble response characteristics of two high-fidelity amplifiers which are electrically separated but aurally related for stereophonic reproductions.

According to the present invention, there is associated with high-fidelity receiving equipment, for example, a graph Which exhibits rectangular coordinate axes of first and second electrical conditions. Associated with the aforementioned graph are at least two flexible indicating rods each having a minor portion thereof fixedly disposed nited States Patent i 2,918,894 Patented Dec. 29, 1959' with respect to a' point or area on said graph and a major portion thereof adapted for selective displacement in a plane parallel to the aforementioned graph. Means are provided for accomplishing such selective displacements of the major portions of each of the indicating rods, such means being mechanically coupled to respective electrical controls, actuation of which controls results in electrical phenomena as shall be physically indicated by the indicating rods in their disposition with respect to the graph. Thus, in the case of stereophonic high-fidelity receiving equipment, the coordinate axes of the graph represent gain versus frequency and the displacement of each of the indicating rods with respect to the graph is responsive to the adjustment of the bass and treble controls related to each separate amplifier-speaker system. Hence, the operator of the equipment can readily determine not only the relative bass and treble settings for a particular amplifier but also the relative bass and treble settings of one amplifier with respect to any one or more amplifiers, all being done by visual indications without dependence upon aural responses.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages thereof, may best be understood by reference to the following description, taken in connection with the accompanying drawings, in which,

Figure 1 is a diagrammatic frontal view of apparatus in accordance with the present invention, the chassis and other parts, such as cover and mounting plates, being eliminated for clarity of illustration.

Figure 2 is an enlarged front perspective view of a part of the apparatus illustrated in Figure 1.

Figure 3 is an enlarged frontal view of one of the slider elements.

Figure 4 is a side view of the element illustrated in Figure 3 as seen from the right side thereof.

In Figure 1 is shown a graph 10 having rectangular coordinate axes 11 and 12 representing frequency (in cycles per second) and gain (in decibels), respectively. Frequency and gain increments are identified by appropriate numerals, as are shown on the graph. Flexible indicating rod 13 includes a bass major portion 14, a treble major portion 15, and a central minor portion (not shown) secured behind and by mounting member 16 to the chassis. Flexible indicating rod 17 includes bass major portion 18, treble major portion 19, and a central minor portion (not shown) also secured behind and by mounting member 16 to the chassis. The end regions of bass portions 14 and 18 of flexible indicating rod 13 and 17, respectively, cooperate with C-

shaped finger portions

20 and 21 of the

slider elements

22 and 23, respectively. The end regions of

treble portions

15 and 19 of flexible indicating rods 13 and 17, respectively, cooperate with C-

shaped finger portions

24 and 25 of

slider elements

26 and 27, respectively.

Figure 2 shows the mechanical apparatus seen on the right side of Figure 1 disassociated from the rest of the apparatus for the sake of convenience of illustration. In Figure 1, certain of the elements are visually in line with each other; viewing Figure 2 in conjunction with Figure 1, it can be seen that

idler wheels

28, 29 and 30 are rotatably mounted upon

axis pins

31, 32 and 33, respectively, and that

idler wheels

34, 35 and 36 are similarly mounted upon the

same axis pins

31, 32 and 3'3, respectively. Guide wire 37 is secured to element 26 at hole 38 and then passes consecutively over

idler wheels

29 and 30, drive wheel 39, idler wheel 28, and then is secured to the opposite side of element 26 at hole 40. Guide wire 37 may be either in frictional engagement with drive wheel 39 or else have two ends tied to drive wheel 39, with several turns of wire lapped about wheel 39 in a manner not shown but Well known in the art. Axis

pins

31, 32 and 33 are immovably secured to the chassis (not shown). Drive wheel 39 is secured to drive pin 41 which is rotatably mounted upon the chassis. Secured to drive pin 41 is driven gear 42 which is in driven engagement With drive gear 43. Drive gear 43 is secured to inner concentric drive-shaft 44, as is first treble control knob 45. First treble control element 46 is secured to the chassis and is internally varied in its electrical values by rotational displacement of shaft 44 through rotational movement of control knob 45 for variation of the treble response characteristics of a first amplifier. Outer concentric drive-shaft 47 is secured to second treble control knob 48 and drive wheel 49. Second treble control element St) is secured to the chassis and is internally varied in its electrical values by rotational displacement of outer concentric drive-shaft 47 through rotational movement of knob 48 for variation of the treble response characteristics of a second amplifier. In a manner well known in the art, outer concentric drive-shaft 47 is rotatably secured to the chassis and inner concentric drive-shaft 44 is freely rotatable within knob 48, outer drive-shaft 47, drive Wheel 49 and element 51). Guide Wire 51 is secured to slider element 27, engaged with drive Wheel 49, and translationally movable in response to rotation of control knob 48.

Turning to Figures 3 and 4, it can be seen that slider element 26 is provided with a C-shaped finger portion 24 having an opening 52 therein through which the end region 53 of flexible rod major portion is slidably projected to allow for the angular positioning and horizontal movement of end region 53 while obtaining vertical displacement thereof.

Preferably, flexible rods 13 and 17 are disposed in proximity with both each other and graph 10, and move within parallel planes to aid the operator in the comparative disposition of the flexible rods for the purpose of obtaining the desired stereophonic response from the two separated speaker systems which are driven by the two amplifier systems.

Returning to Figure 1, it can be seen that the bass response characteristics are controlled and indicated for the two separate amplifier systems by apparatus identical to that of Figure 2, being the mirror image thereof in Figure 1.

Of course, in actual practice, the only apparatus of Figure 1 visible outside the cabinet containing the apparatus would be the flexible rods, the graph, and the control knobs. All of the gear and wheel systems would be disposed behind a cover-plate for the cabinet and chassis.

While particular embodiments of the present invention have been shown and described, it will be obvious to'those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects, and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. in combination, a planar graph having first and second rectangular coordinate axes each representing a respective electrical condition, a plurality of pairs of flexible indicating rods disposed in proximity with said graph, each of said flexible rods having a minor portion and a major portion, said minor portions being fixedly disposed with respect to both each other and said graph, said major portions being adapted for selective displacement in respective planes parallel to said graph and each other, a plurality of independently rotationally adjustable electrical controls, and a plurality of means intercoupling said electrical controls with respective ones of said flexible rods for varying the dispositions of said major portions of said rods in response to the rotational displacements of said controls to indicate visually the electrical phenomena resulting from the adjustments of said controls, said plurality of intercoupling means each including a slider element having means for slidably retaining said major portion of a respective one of said flexible rods, said slider elements each being adapted for translational displacement with respect to each other and said graph, a plurality of guide wires each secured to a respective one of said slider elements, and a plurality of pairs of drive means, each of said drive means being cooperably associated with a respective one of said electrical controls and a respective one of said guide wires, each of said pairs of drive means being cooperably associated with a respective one of said pairs of flexible indicating rods, and each of said pairs of drive means comprising first and second drive wheels and first and second concentric shafts, each of said guide wires being disposed about a respective one of said drive wheels in frictional relationship, and each of said shafts being connected to a respective one of said electrical controls.

2. Apparatus for visually displaying the bass and treble response characteristics of each of a pair of amplifier systems in respective driving relationship to a pair of separately located speaker systems adapted for stereophonic reproduction including, in combination: a planar graph having rectangular coordinate axes representing frequency versus gain; first and second flexible indicating rods each having a bass indicating portion, a treble indicating portion, and a minor central portion; mounting means securing said minor central portions of said flexible indicating rods in fixed proximal relationship with respect to said graph at a central region thereof; first and second independently rotationally adjustable bass controls; first and second independently rotationally adjustable treble controls; first, second, third, and fourth means intercoupling said first bass control, said second bass control, said first treble control and said second treble control, respectively, with said bass portion of said first indicating rod, said bass portion of said second indicating rod, said treble portion of said first indicating rod, and said treble portion of said second indicating rod, respectively, Whereby said portions of said rods are varied in dispositions with respect to said graph in response to the rotational displacements of said controls to indicate visually the respective response characteristics resulting from the adjustments of said controls, said intercoupling means each including a slider element having means for slidably retaining said major portion of a respective one of said flexible rods, said slider element being adapted for translational displacement, and a guide wire attached to said slider element; a first drive means cooperatively associated with said first and second inter-coupling means; and a second drive means cooperatively associated With said third and fourth intercoupling means, each of said drive means comprising first and second drive wheels and first and second concentric shafts, each of said guide wires being disposed about a respective one of said drive wheels in frictional relationship, and each of said shafts being connected to a respective one of said electrical controls.

Bennett Feb. 19, 1957 Jahns July 1, 1958