US2459351A

US2459351A - Illuminated test device

Info

Publication number: US2459351A
Application number: US549471A
Authority: US
Inventors: Weincord Maurice
Original assignee: Individual
Current assignee: Individual
Priority date: 1944-08-14
Filing date: 1944-08-14
Publication date: 1949-01-18
Anticipated expiration: 1966-01-18

Description

Jan. 18, 1949. E

ILLUMINATED TEST DEVICE Filed Aug. 14, 1944 Patented Jan. 18, 1949 UNITED STATES- PATENT OFFICE 1 Claim. (Cl. 175183) The present invention relates to an apparatus having particular utility as a testing and illuminating device for use by electricians and electronic service and assembly personnel in performing various operations that are required in conjunction with making tests and observations upon intricate electrical circuit systems, such as radio circuits telephone and telegraph apparatus and the like.

An object of the present invention is to provide an electrically lighted apparatus having testing leads or terminal prods which may be utilized in making various types of test observations pertaining to circuit continuity and comparative resistance drop.

The lamp element in this type of device is intended to be used both to illuminate inaccessible or darkened recesses within an apparatus and as a target for denoting by intensity variations the resistance factors of electrical elements or circuit components.

For a more comprehensive understanding of the present invention reference will now be had to the accompanying drawing and to the following detailed specification in which like reference characters are employed to designate corresponding parts throughout and in which:

Fig. 1 is a transverse sectional view of an apparatus embodying certain other features of the present invention;

Fig. 2 is a transverse sectional view taken approximately on line 2-2 of Fig. 1; and

Fig. 3 is a diagrammatic circuit illustrating schematically how an apparatus according to Figs. 1 and 2 may be designed utilizing an inductance coupling as an electric power source.

Referring now more particularly to the accompanying drawing, the reference numeral 4! will be observed as indicating a tubular housing pref erably molded of electrically non-conductive material and threaded internally as at l2 to receive the end plug 42 which is similarly threaded and the rim of which may be peripherally fluted for convenience in manipulation.

The forward end of the tubular case 4! is semispherically curved as at 15 and thereat provided with a concentric opening it through which a magnification bead ll integrally formed with an electric bulb 48 may protrude. Bulb 48 includes an internal lighting element II and is hermetically sealed into a conventional type of screw threaded base l9 which is received between the convolutions of a specially shaped compression spring 49, the forward convolutions of which are of greater diameter and secured as at 26 by welding or otherwise to a prod 5| and the rearward convolutions 2! of which are also enlarged to seat within suitable provisions in an insulated collar 53 that fits over the forward portion of a battery comprising the cells 46 and 4'! encased in insulating jackets after the conventional manner and practice.

The end plug 42 is molded with a convenience ear terminal 32 through which the electrical conductor 54 may be inserted behind the place at which the conductor extremity 43 is secured as by soldering 44 to the electrically conductive sleeve 45. The wire 54, which may be a longitudinal eX- tension of the endmost convolution of the spring 49, is insulated from the cells by reason of the jackets carried by the latter members and serves the purpose of facilitating rapid assembly of the parts by afiording a means for placing the target lamp and its socket spring during the original insertion into the case 4! as well as during subsequent insertions such as are necessary following lamp replacements.

When the apparatus is assembled in the manner illustrated in Fig. 1 with the base plug 42 screwed tightly forward and the terminal 35 of the foremost cell 47 in contact with the center contact element 34 of the lamp base It, the apparatus is conditioned for continuity testing, that is, by engaging the alligator cord terminal onto the grounded chassis of an apparatus under test, the lamp may be lighted by engaging the test prod 5| at any point in the subject circuit.

By withdrawing the plug screw 42 until a space is afiorded between the cell terminal 35 and the contact 34 of the lamp base, the apparatus may be employed as a plunger operated flashlight either in conjunction with continuity testing, or by engaging the prod 5! with the alligator terminal 55 the target lamp 48 may be lighted when the prod 5| is forced inwardly by touching the object to be observed.

When the plug 42 is fully inserted and with the alligator terminal 55 engaging the prod 5!, the apparatus is continuously lighted and may be thus employed without requiring the prod compression operation as aforedescribed.

It is to be understood that in various types of electrical manufacturing and assembly operations as well as in laboratory experimental work these Various modes of functioning lend themselves particularly to the convenience of testing and cheer ing intricate circuit systems augmenting their test apparatus and supplying local visibility where otherwise shadows or inadequate lighting render inaccessible parts of an apparatus susceptible to erroneous assembly as a result of poor visibility.

In factory assembly test operations where a work laboratory may consist of a long table provided with line supply outlets, a transformer may be used instead of the battery featured in Figs. 1 and 2 as indicated diagrammatically in Fig. 3 at 6!. The secondary voltage is appropriate to the requirements of target lamp 62 and the test prod or alligator clamp terminal 63 may be of the same type featured in Figs. 1 and 2 as may also the probe rod 64 resemble the corresponding element in "the battery type of apparatus;

* While the present invention has been explained and described with reference to specific illustrations it is to be understood nevertheless that obvious margins of variation may be incorporated without departing from the essence't'hereoL-accordingly it is not intended to be limited by the specific details in the accompanying drawing nor by the particular language of the foregoing specification except as indicated in the hereunto appended claim.

The invention claimed is:

A circuit continuity tester comprising a tubular housing member having a visibility opening at one end and an accessibility opening at its other end, an illumination bulb disposed adjacent said visibility, an electrically conductive'wire helix having its intermediate convolutions constricted for screw threaded engagement with the filament contact base of said bulb andhaving its extreme convolutions radially and longitudinally distended for compressive engagement with the internal forward wall of said housing on the one hand and with the foremost end of a battery of cells con-,

stituting a power unit on'the other hand, an electrically conductive prod bar secured to the foremost ones of said distended convolutions and extending through a journal opening-of said housing whereby said helix may be compressed durin abutment engagement of said prod bar, and a closure plug for said housing having an electrically conductive terminal plug to engage the rearmost end of said battery of cells and including in electrical engagement therewith a flexible lead wire terminating with a test engagement terminal element, said plug being screw adjustable throughout a distance to permit contactual engagement between said illuminatingbulb and the foremost terminal of abattery cell in "opposition to the tension of said helix spring or to be spaced therefrom so that the device may be usedas a prod controlled illumination tester or as a continuous illumination under corresponding conditions of test requirements.

MAURICE REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS WEINCORD.

Number Name Date 1,386,474 Vince Aug. 2, 1921 1,653,669 Rydzy Dec. 27, 1927 2,104,888 Spahr Jan. 11, 1938 2,156,319 Steele May 2, 1939 2,164,148 Swanson June 27,1939 2,204,136 King et a1 June 11,1940 2,249,690 Gelardin July 15, 1941 2,256,129 Tainer Sept. 16, 19-41 2,261,320 Williams Nov. .4, 1941 FOREIGN PATENTS Number Country Date a 259,275 Great Britain 861911.20, "1926