US2684410A

US2684410A - Blanking switch associated with variable wave guide antenna

Info

Publication number: US2684410A
Application number: US212098A
Authority: US
Inventors: Romar E Stein
Original assignee: Gilfillan Bros Inc
Current assignee: Gilfillan Bros Inc
Priority date: 1951-02-21
Filing date: 1951-02-21
Publication date: 1954-07-20
Anticipated expiration: 1971-07-20

Description

July 20, 1954 5, gram 2,684,410

BLANKING SWITCH ASSOCIATED WITH VARIABLE WAVE GUIDE ANTENNA Filed Feb. 21, 1951 2 Sheets-Sheet l INVENTOR. aw?

prraewsys' lllwT July 20, 1954 R. E. STEIN 2,684,410

Filed Feb. 21, 1951 2 Sheets-Sheet 2 i Fig.5.

[Zr G42 5O 55 4| 29 5| O 55 25 40 \x \X 201142 E. 375/, 6 INVENTOR.

Patented July 20, 1954 BLANKING SWITCH ASSOCIATED WITH VARIABLE ill/AVE GUIDE ANTENNA Romar E. Stein, Los Angeles, Calif., assignor to Gilfillan Bros., Inc., Los Angeles, Calif., a corporation of California Application February 21, 1951, Serial No. 212,098

6 Claims.

The present invention relates to an improved switch construction characterized by its adjustment features, and is particularly useful for controlling an electrical circuit associated with the movable wave guide element of a radar antenna for energizing related circuits in predetermined time relationship with respect to the scanning movement of the radiated antenna beam.

in radar installations, a variable wave guide antenna is used for purposes of radiating an antenna beam in a predetermined direction, the direction being cyclically varied, to obtain a scanningor sweeping of such antenna beam in space by oscillating a wave guide element. Other parts of the radar installation require related cir cuits to be energized in accordance with the particular angular position of the radiating beam, and for that purpose, as shown herein, a switch is coupled to the oscillatory wave guide element so as to be operated in synchronism, at predetermined times, in relationship to the scanning movement of the antenna beam.

The present invention therefore contemplates the provision of an improved switch operating in synchronism with such oscillatory wave guide member, the switch being constructed so as to give long life and being capable of precise adjustment whereby the switch may be adjusted to compensate for mechanical variations in different antennas with which it is used.

An object of the present invention, therefore, is to provide an improved switch construction for accomplishing the aforementioned purposes.

A specific object of the present invention is to provide an improved switch of this character which is closed for a selected period of time while the associated wave guide member moves between its extreme limits of oscillatory movement.

Another specific object of the present invention is to provide an improved switch of the type mentioned in the previous paragraph which incorporates adjustment means whereby the switch may be adjusted to open at any point with re spect to either end of travel of the oscillatory wave guide member.

Another specific object of the present invention is to provide an improved switch of this character which may be adjusted to open at predetermined points with respect to either end of movement of the oscillatory wave guide member, and further incorporates adjustment means whereby the period during which the switch is closed may be adjusted with respect to any selected portion of travel of the oscillatory member.

guide Another specific object of the present invention is to provide an improved switch of this character which is of rugged construction and capable of being operated over a long period of time without failure.

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

Figure 1 is a view in end elevation of a switch associated with a variable wave guide radar antenna in accordance with features of the present invention, certain parts of the structure shown being broken away and fragmented for purposes of more clearly illustrating internal structure;

Figure 2 is a View in plan of the switch shown in Figure l, but with certain parts thereof fragmented and sectioned for purposes of showing internal structure;

Figure 3 is a view taken generally as indicated by the line 3-3 in Figure l; and

Figure 4 is a sectional view taken on the line 4-4 of Figure 3.

Referring to Figure 1, the switch casing housing or base I0 is firmly mounted as, for example, by releasable bolts l i to the stationary wave guide element l2 of the radar antenna l3. The other wave guide element M, which cooperates with the stationary guide element l2, is oscillated vertically in Figure l, as indicated by the arrows l5, by conventional means which are not shown here. The effect of such oscillatory movement represented by the arrows i5 is to cyclically vary the spacing, i. e., the so-called A-dimension, defined by the operation of the legs lZA, MA on the stationary and movable guide members, respectively. By thus cyclically varying the spacing, i. e., the so-called A-dimension, a scanning movement is imparted to the highly directional antenna beam radiated by a series of dipoles it, each of which are mounted 011 the guide member [2 with a probe thereof extending into the variable width wave guide defined by the legs (2A, MA. The stationary guide member l2 may have mounted thereon a longitudinally extending parasitic reflector IT.

The switch in the casing 10 is operated in timed relationship with movement of the variable wave guide member 14, and the time during which it is operated, as described in detail hereinafter,

may be adjusted with respect to either end of travel of the guide member I4, and further may be adjusted to remain closed during any selected period corresponding to a selected period of travel of the guide member i i. For purposes of actuating the switch, which has the general reference numeral is (such switch iii, in fact, comprising eight switches as described hereinafter), a pair of upwardly extending arms 29 (Figures 1 and 3) is interconnected between the movable guide member ill and the movable portion 22 of the switch is. The lower ends of these arms are releasably fastened to the guide member it by machine bolts 23.

Actually, the switch l9 includes four identically constructed

switches

24, 24, 24, 24 in the upper deck (Figure 1) and four identically constructed

switches

25, 25, 25, 25 in the lower deck. Corresponding ones of such switches, 24, 25, as shown in Figure 1, are serially connected to an upper deck terminal 26 and a lower deck terminal 2?.

Briefly, the upper deck switch :24 .is actuated in upward movement of the guide member l4, and the lower deck switch 25 is actuated in downward movement of the guide member [4, and the point at which the

switches

24, 25 are operated, i. e., opened, with respect to the upper and lower limits of travel of the guide member I4,

may be adjusted by corresponding upper and lower

deck adjustment screws

28 and 29. Since there are four upper deck switches 24, there are four corresponding adjustment screws 28., and likewise there is an adjustment screw 29 for each of the four lower deck switches 25. Further, by adjusting the angular position of the upper cam 30, each of the upper deck switches 2 may be adjusted in unison; likewise, by adjusting the angular position of the lower cam ti, each of the lower deck switches 25 may be adjusted in unison.

It is observed, with reference to Figure 1, that each of the switches i i, 25 have a common element, namely, the generally V-shaped spring element 32 which is affixed to the housing Hi by bolt 33 with contact elements mounted on each of its free ends, such contact elements cooperating with like contact elements mounted on the insulated leaf springs 3t, 35. These

leaf springs

34, 35 are mounted on the post 3'? of insulating material, which is bolted to the casing I8 with projecting ends of

such leaf springs

34, 35 providing terminals 26, it is observed that the V-shaped switch spring element 32 is insulated from the casing iii.

It is observed, as clearly shown in Figure 4, that the free ends of the V-shaped spring switch element 32 cooperates with the rounded reduced ends of the adjustment screws 23, 29, in such a manner that corresponding free ends may be adjusted physically with reference to the

corresponding spring elements

34, 35 whereby the point at which the

switches

24, 25 are operated, i. e., opened, with respect to upper and lower movement of the arm 28, may be adjusted. Various means may be used to lock the adjustment screws 28, 2% in their adjusted position, and such means, since they are preferred, are shown herein as looking plates as, all which cooperate with the shanks of the screws 28, 2Q, respectively, to secure the same against movement.

The switches 2:8, 25 actually are both normally closed switches, as shown in Figure 4, and switch 2 2 is caused to be opened upon engagement of the switch 25 is opened upon engagement of the cam 3i with the spring element 35. Both of these

cam members

30, 3| have their opposite ends supported on the upper ends of the arms 28, 2s, one end of these cams 38, 3! being slip fitted into one of the arms 20, whereas the other end of these

cams

39, 3! is locked to the other arm 20, as shown :in Figure l, by a clamping plate ii, the opposite ends of which are bolted to the arm 2E so as to clamp each of the cams 3e, 3! between the plate GI and the upper end of such arm 20.

Each of these

cams

30, 3! may comprise simply an insulating rod with a smaller rod passing through an eccentrically located bore in the larger rod, and with both the larger and smaller rods afiixed together, as for example, by a pin or set screw. Such smaller rod has one of its ends provided with a hexagon head and screw driver adjustment slot, so that the assembly comprising such larger and smaller rods may be rotated to different adjusted positions once the clamping plate All is released.

It is evident that adjustment or the cam 30 efifects the time at which each of the upper deck switches 24 is operated; similarly, adjustment of the lower cam 31 effects the time at which each of the lower deck switches 25 is operated.

ifferent electrical circuits connected to terminals 2t, 2? are thus normally closed in intermediate position of the oscillatory wave guide member 24 which, as mentioned previously, oscillates in the direction indicated by the arrows It in Figure 1. It is only when the guide member i4 is moved towards either one of its extreme positions that either switch 2 or 25, as the case may be, is interrupted to thereby interrupt such electrical control circuit which includes, for purposes of reference, the terminal 2%, switch element 24, switch element 25 and terminal It is obvious from the foregoing description that the point at which the switch 2%, 25 is operated with reference to the angular position of the antenna beam radiated from the antenna 13 may be adjusted individually by

corresponding adjustment screws

28, 29 which are thus capable of providing a compensatory effect for unpredictable operation of the antenna.

.After once installing the composite switch It on the wave guide antenna 13, the

individual switches

24, 25 are adjusted by adjustment of the corresponding adjustment screws 25, 2s. Later, when it is desired to install the same switch on a difierent antenna of the same novel dimensions, or to re-install the same switch on an antenna after it has been repaired, or, more important, upon replacement of a magnetron, adjustment of each of the switches E lor 25 in unison may be effected by adjustment of the

corresponding cam

35, 3|, thereby avoiding the necessity of adjusting each of the

screws

28, 29, individually.

While the 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 maybe 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. Ina switch of the character described, a housing, :a generally V-shaped spring element having an intermediate portion thereof affixed to said housing, a pair of cantilever supported spring elements each cooperating with opposite free ends of said V-shaped spring element, a pair of adjustment screws mounted on said housing and adapted to engage and move corresponding opposite legs of said Vshaped spring element to different adjusted positions, a movable switch actuating element including a pair of generally parallel extending adjustable cams arranged to engage and. move opposite ones of said pair of cantilever supported spring elements.

2. In a switch of the character described, a switch base, a generally V-shaped spring switch element attached at a point intermediate its ends to said base, means mounted on said base for adjusting independently the position of opposite free ends of said V-shaped element, a pair of cantilever supported spring elements having opposite free ends thereof cooperating with opposite free ends of said V-shaped element to form a pair of switches, a movable switch actuating member mounted for movement relative to said base and comprising a pair of adjustably positioned cams engageable with opposite ones of said cantilever supported spring elements.

3. In a switch of the character described, a base, a first pair of resilient cantilever supported switch arms on said base, adjustable means on said base for adjusting the position of the free ends of each or" said arms, a second pair of resilient cantilever supported switch arms cooperating respectively with opposite ones of the first pair of switch arms to provide a pair of switches which remain normally closed in the adjustable range of said adjustable means, switch actuating means movably mounted .with respect to said base, said switch actuating means including a pair of adjustably positioned elements adapted to engage and to move corresponding ones of said second pair of cantilever supported switch arms.

a. In an arrangement of the character described, a movable element reciprocablein a first direction and a stationary element, a switch base aiiixed stationarily with respect to said stationary element, a first pair of cantilever supported switch arms mounted on said base, a pair of adjustment screws having their longitudinal axes extending generally perpendicular to said first direction and engaging opposite ones of said air of switch elements to adjust their respective positions, a second pair of cantilever supported switch eiements cooperating with corresponding ones of said first pair of switch elements to provide a pair of serially connected switches, a switch actuating member aifixed to said movable element, said switch actuating member comprising a pair of adjustably positioned cams each functioning to engage and to move corresponding ones of said second pair of switch elements.

5. In a switch of the character described, a base, a first pair of resilient cantilever supported switch elements mounted on said base, a pair of adjusting elements on said base cooperating with a corresponding one of said pair of resilient switch elements to adjust their respective positions, a second pair of cantilever supported switch elements on said base and engageable with said first pair of switch elements in the adjustment range of said adjusting elements, a reciprocable switch actuating member, means mounting said reciprocable switch actuating member for reciprocal movement with respect to said base, said switch actuating member including a pair of adjustably positioned elements functioning to engage and move a corresponding one of said second pair of cantilever supported switch elements.

6. In an arrangement of the character described, a switch base, a series of generally V- shaped spring switch elements each being aligned and having an intermediate portion thereof af fixed to said base, each of said generally V- shaped switch elements having associated therewith a pair of adjustment screws, adjustably positioned on said base and functioning to engage and to move opposite free ends of a corresponding one of said V-shaped spring elements to different adjusted positions, a series of pairs of cantilever supported switch elements each having opposite free ends thereof cooperating with opposite free ends of said V-shaped spring elements, a reciprocable switch actuating member, said switch actuating member carrying a pair of cam members which extend parallel to each other and parallel to the aligned axes of the first and secand mentioned series of switch elements, said cam members functioning to engage and to move in unison opposite ones of said second series of switch elements.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,671,615 Spahr May 29, 1928 1,89 i,025 Dennison et al Jan. 10, 1933 2,079,252 I-Iealy May 4, 1937 2,415,242 I-Iershberger Feb. 4, 1947 2,520,270 Batcheller Aug. 29, 1950