US 2968804 A
Description (OCR text may contain errors)
Jan. 17, 1961 R. F. BUFFINGTON MAIL BOX INDICATOR Filed March 19, 195? INVEN TOR. RAYMOND F. BUFFINGTON BY 6450a &- flmeugw ATTORNE YS United States Patent MAIL BOX INDICATOR Raymond F. Bnfiington, 1205 Harlmess St., Manhattan Beach, (Ialif.
Filed Mar. 19, 1957, Ser. No. 647,143
2 Claims. (Cl. 340-281) This invention relates generally to apparatus for indicating the presence or absence of mail in a mail box, and more particularly to a remotely controlled device in which the presence or absence of mail may be determined from a remote distance such as inside a room in a house or apartment.
Many devices have been proposed heretofore for indicating the presence or absence of mail in mail boxes. Such devices find their most useful application in rural districts in which the mail box itself is located near a main highway or road, usually a considerable distance from the residence.
Some such systems, for example,
have comprised pressure responsive electrical switches disposed within the mail box such that the weight of mail or other received material depresses the switch to close an electrical circuit and provide an indication in the dwelling of the presence of mail. Other remote signaling devices constitute mechanical variations of the pressure switch. The majority of such systems employ movable mechanical parts which are subject to weathering particularly in rural districts and thus are liable not to operate as a result of corrosion or rusting of parts.
Even if the mail box is well protected, some of the parcels of mail itself may be wet or partially covered with snow which, when placed in the box, may cause damage to the mechanical pressure switch or other apparatus therein for indicating the presence of the mail.
Another difi'iculty with heretofore proposed indicators of the mechanical type is the possibility of mail not actually resting on the particular indicator. For example, if the item of mail is of abnormal size such that it is placed in a box in a diagonal or possibly folded position, only the edge corners of the box may be engaged by the mail leaving the floor of the box substantially free whereby no indication will be given of its presence. Also, a single item of mail such as a postcard may not have sufiicient weight to operate the indicator. In certain instances such as in city mail boxes especially those used in apartment dwellings, the boxes may be of a shape that cannot readily accommodate mechanical apparatus to indicate the presence of mail. These boxes are normally oblong in a vertical direction and the letters or other mail is placed vertically in the box whereby the chances of the lower edge of the letter contacting a pressure switch or the like is not always assured, particularly in the case of folded items that protrude from the top of the box.
Bearing the above in mind, it is a primary object of the present invention to provide a greatly improved remote signaling device for indicating the presence or absence of mail in a mail box of either the rural or city type which does not depend for its operation on moving mechanical parts within the box itself, whereby a very reliable and substantially maintenance free indicator is provided.
More particularly, it is an object of this invention to provide a mail box indicating device of the above type in which the presence or absence of mail will be incli- 2,968,804 Ce Patented Jan. 17, 1961 cated wholly independently of the shape or weight of the mail itself so that abnormally large mail pieces requiring folding, even small postcards of little weight, will be indicated.
Still another object is to provide a device of the above type which is normally in an off position so that no power is required for its operation except at the particular instance when it is desired to ascertain whether or not mail is present.
Yet another object is to provide a remote mail box indicating device which is readily adapted for apartment mail boxes wherein a common power source is provided for a plurality of indicators so that the application of the invention to different mail boxes in an apartment dwelling is greatly facilitated.
These and many other objects and advantages of the present invention are attained, briefly, by providing a photoelectric apparatus mounted on the mail box in such a manner that a beam of light is caused to traverse the volume of the box from a light source to a photoelectric cell. Suitable electrical wires for energizing the light source and for communicating signals from the photocell pass from the apparatus in the mail box to a remote location such as a country dwelling house or an apartment. Within the house or apartment there is provided an indicating means including a light or buzzer adapted to visually or audibly indicate the presence or absence of mail upon operating a switch or a button. If the indicator light goes on or the buzzer sounds in response to pressing of the button, the operator is informed that mail is present. On the other hand, if no light or sound results, then the operator is apprised that there is no mail in the box. Alternatively, the arrangement may be such that the absence of mail will be indicated by a shining of the light or a sounding of the buzzer whereas the presence of mail will result in the light or buzzer not working.
In a preferred embodiment of the device especially useful for apartment house mail boxes, there are provided a plurality of photoelectric cell systems adapted for use with a plurality of mail boxes and a single powerpacl; for supplying proper energizing voltages to these units as well as power for operating the remote indicating lights, buzzers or other indicating means. In accordance with an important feature of the invention, there is provided a reflector adapted to co-operate with the light source and the photoelectric cell such that the beam will traverse the volume of the mail box along two separated paths whereby at least one of the paths will invariably be interrupted by the presence of mail to cause the indicating means to be actuated.
A better understanding of the invention will be had by referring to the accompanying drawings, in which:
Figure l is a highly schematic diagram illustrating by way of example only one embodiment of the present invention useful for rural type mail boxes in which the electrical circuit associated therewith is shown in a simplified schematic manner; and,
Figure 2 is a perspective view of the contemplated arrangement of the invention with respect to the indicating of the presence or absence of mail in apartment mail boxes such as are used in cities.
Referring first to Figure 1, there is illustrated a conventional rural type mail box 10 provided with a hinged front cover 11 for receiving mail such as the envelope 12. Mounted on the mail box 10 is a photoelectric apparatus comprising a light source 13 adapted to direct a beam of light to a photoelectric cell 14 as indicated by the arrows. This beam traverses the inner volume of the mail box and will be interrupted by the presence of any mail such as the letter envelope 12. The light source 13 may be energized by a pair of leads 15 and 16 3 passing to a remote location such as the interior of a dwelling. These leads are connected across a switch button 17 in series with a battery 18.
The photoelectric cell 14 is connected by means of a pair of leads 19 and 20 to actuate a relay coil 21 having a switch arm 21 connected in series with an indicator such as a lamp 22. The switch arm 21 and lamp 22 are connected across the switch button 17 and battery 18 in parallel with the leads 15 and 16 as shown. The relay coil 21 is adapted to be energized in response to .acth sition of the photoelectric cell 14 in the mail box when struck by the light beam from the source 13.
In operation, upon depression of the switch button 17 by the dweller who wishes to ascertain the presence or absence of mail, electrical energy from battery source 18 will pass through the leads 15 and 16 to light the light source 13 in the mail box 10. Assume for the moment that there is no mail in the box. In this event, the light beam will strike the photoelectric cell 14 generating a signal which will be passed by the leads 19 and 20 to the relay coil 21 energizing the same. Energization of the relay coil 21 will move the switch arm 21 from its normally closed position as shown, to the open contact thereby disconnecting the indicating light 22 from across the battery 18 and switch 17. Therefore, the absence of mail in the box will be indicated by the fact that the lamp 22 does not go on.
On the other hand, if a letter such as the letter 12 is present, the beam from the light source 13 upon energization thereof by closing of the switch button 17, will be interrupted and shielded from the photoelectric cell 14 whereby no signal will be present in the coil 21 and thus the switch arm 21 will remain in its normally closed position. In such position, the lamp 22 will then light indicating to the operator that mail is present in the box.
It should be noted that there may be a slight mechanical delay in the operation of the relay coil 21 and the switch arm 21' after the button 1'7 is closed in the event no mail is present. Therefore, the operator will observe first a slight flicker of the lamp 22 immediately upon the initial closing of the button 17. This flicking on of the light 22 briefly will occur during the time the switch 17 is closed and before the relay 21 has time to move the arm 21' downwardly to its open position. This small light flick will serve to indicate that the apparatus is operating. On the other hand, it should be noted that by making the relay coil 21 and switch arm 21' a normally open relay such that the arm 21 will assume its solid line position only upon energization of the coil 21, then the presence of mail will be indicated by first a slight flicker and then absence of shining of the light 22, whereas its absence would be indicated by a steady shining of light 22. It should be understood, of course, that the circuit may be designed to a oid any flicker if desired.
Further, while Figure 1. illustrates one type of electrical circuit in combination with the photoelectric apparatus, which will enable the presence or absence of mail to be indicated, it will be readily understood that other electrical systems may be used. Referring now to Figure 2, there is illustrated a remote indicating device for use with those types of mail boxes used in apartment houses. As shown, by way of example, there are provided two adjacent mail boxes 23 and 24 which may comprise a portion of a row of many mail boxes. Each of the mail boxes such as the mail boxes 23 and 24 has associated with it a photoelectric apparatus 25 or 26 adapted to 'be mounted on the rear of the boxes in an out of the way position. Each of the photoelectric apparatuses is identical and, therefore, description of one will suflice for all. The apparatus 26, for example, includes a light source 27 adapted to direct a light beam into a photoelectric cell 28 by reflecting the beam off a reflector 29 secured to the inside of the door of the box 24. By this arrangement, two paths of light traverse the inner volume of the box and increase the chances of the beam being broken should a very narrow piece of mail, such as a mailing tube which might avoid a single beam, be inserted in the box.
The energization for the light source 27 and the sig nals from the photoelectric cell 28 are communicated by means of a four pronged socket 30 adapted to co-operate with a plug on a power line 31 leading to a central power-pack 32. From the same power-pack 32 there may be provided another line 33 passing up to a mounting plate 34 on the wall of a persons apartment, such as apartment number four. The mounting plate 34 includes a button 35 and an indicating light 36. The button 35 and indicating light 36 would correspond to the switch button 17 and light 22 of Figure 1 and the circuit within the power-pack 32, the mounting plate 34, and the photoelectric apparatus 26 may be the same as schematically illustrated in Figure 1. It will be noted that the power-pack 32 contains a number of other outlets for providing electrical energy for operating the other photoelectric systems associated with other mail boxes in the same building such as for the apartments 1, 2 and 3. By this arrangement, several devices may be readily and economically installed in compact packages behind the various apartment mail boxes and simple connecting conductors passed to a central powerack located in the cellar of the building from which other suitable conductors lead up to the indicating devices disposed in the various kitchens, for example, of the apartments themselves.
The operation of the apparatus illustrated in Figure 2 is the same as that in Figure 1. When the dweller wishes to ascertain the presence or absence of mail, he or she simply depresses the button 35. If the circuit arrangement is as shown in Figure 1 wherein the relay arm 21 is normally closed and opens only upon energization of the relay coil 21, the continuous shining of the light 36 will indicate the presence of mail whereas its failure to shine continuously, will indicate the absence of mail.
From the above described arrangements, it will be seen that the present invention provides a greatly improved remote indicating device for mail boxes which does not rely upon any movable mechanical apparatus in the box itself. Thus, the possibilities of wearing out of mechanical parts due to corrosion or rust are wholly avoided. It is only necessary that the inserted mail intersect the light beam. Further, none of the various electrical elements are energized except upon voluntary operation of the switch button 17 by the operator, and thus all circuits are normally de-energized except when the operator desires to ascertain the presence or absence of mail. The circuit need then only be energized during the particular portion of time that the button 17 is depressed. By the use of a reflector such as the reflector 29, the light beam is doubled in length and thereby the possibility of its being interrupted by a piece of mail is greatly increased. It will be evident that additional reflectors could be used to criss-cross the light path over the interior volume of the mail box. In addition, it will be readily understood that rather than an indicating lamp 22, a simple buzzer or bell may be substituted therefor to give an audible signal as to the presence or absence of mail.
Finally, it will be evident that the buttom 17 may be of a toggle type which may be simply thrown to a set position to hold the apparatus energized wherein if there is no mail present, the relay coil 21 will move theswitch arm 21' to the open position and the indicating light 22 or buzzer will be de-energized. However, with the ap paratus in this condition with the switch button 17 maintained closed, as soon as mail is inserted in the box 10 cordingly, the house dweller is apprised instantly of the exact time when mail is inserted in the box and need not periodically sample the device.
Other modifications within the scope and spirit of this invention will readily occur to those skilled in the art. The invention is, therefore, not to be thought of as limited to the specific embodiments disclosed for illustrative purposes only.
What is claimed is:
1. An apparatus for detecting the presence or absence of mail comprising, in combination: a substantially light proof box structure having a door means providing access to said box for inserting mail; an artifical light source mounted to a first interior portion of said box structure in a position to pass a beam of light, upon energization, from said first interior portion of said box to a second interior portion such that said beam is interrupted if mail is present in said box; a photoelectric cell positioned at said second interior portion to receive said beam of light and provide a control signal only in the absence of any mail; a source of electrical energy; a switch disposed exteriorly of said box for connecting said source of electrical energy to energize said light source upon closing; an indicating means connected to said source and switch to be energized simultaneously with said light source in response to closing of said switch; and a control means connected to said photo-electric cell and said indicating means and responsive to said control signal from said photo-electric cell to de-energize said indicating means, whereby said indicating means is energized and remains energized if mail is present in said box and is momentarily energized and then de-energized if mail is absent from said box.
2. The subject matter of claim 1, including at least one light reflector mounted in the interior portion of said box in a position to reflect said beam of light from said source to said photoelectric cell whereby said beam of light transverses across said interior along paths angulated to each other in passing from said first interior portion to said second interior portion.
References Cited in the file of this patent UNITED STATES PATENTS 1,167,045 Cade et a1. Jan. 4, 1916 1,256,740 'Steiger Feb. 19, 1918 1,342,468 Smith June 8, 1920 2,118,836 Carter May 31, 1938 2,212,211 Pfund Aug. 30, 1940 2,763,853 Grant Sept. 18, 1956