Planetarium

Abstract

A planetarium projection system in which the angle between the precessional and diurnal axes is adjustable includes a projector unit supported for precessional rotation about its axis in a first ring which in turn is rockably supported by opposite radial pins in a second ring which is rotatably supported in a concentric third ring for diurnal motion. The third ring is rockably supported in a vertical yoke for latitude alteration, the yoke being mounted on a base rotatable about a vertical axis. Motor driven pinion and gear assemblies rotate the projector about its precessional axis, the second ring about the diurnal axis and adjust the first ring about the axis of the radial pins to vary the angle between the diurnal and precessional axes, and a control network selectively energizes the individual motors for forward and reverse rotation.

Parent Case Text

REFERENCE TO RELATED APPLICATION

The present application is a continuation-in-part of patent application Ser. No. 172,798, filed Aug. 18, 1971, now abandoned.

Description

BACKGROUND OF THE INVENTION

The present invention relates generally to improvements in planetaria and it relates more particularly to an improved planetarium projection system in which the celestial bodies may be shown as viewed from the earth, moon or selected planets.

Planetaria of the heretofore known types, other than those of the triaxial motion type which are operatively associated with a high grade highly complex computor, can project the images of the heavens and celestial bodies only as seen from the earth. For educational purposes, there is a need to show the celestial bodies as they are seen from the moon or other planets such as Mars, Venus or the like, but a planetarium which will meet this need is intended for a great number of spectators and is large and expensive. Such a planetarium is therefore much too costly for ordinary school use, and even when it is available, unskilled students cannot operate the apparatus in a suitable manner to achieve satisfactory results in the studies of elementary and intermediate astronomy. Thus the benefit derived is very small in spite of the large expenditure.

SUMMARY OF THE INVENTION

A principal object of the present invention is to provide a planetarium which can be operated with a very simple mechanism without employing a computor network to project the images of the heavenly bodies not only as seen from the earth, but also as seen from other planets such as Mars, Venus or the like throughout the diurnal motion thereof.

Another object of this invention is to provide a planetarium which can be operated with extreme ease especially for educational purposes in projecting the images of celestial bodies as seen from planets other than the earth.

A further object of the present invention is to provide a planetarium system of the above nature characterized by its simplicity, low cost, high versatility and ruggedness and reliability.

The above and other objects of the present invention will become apparent from a reading of the following description taken in conjunction with the accompanying drawings which illustrate a preferred embodiment thereof.

In a sense, the present invention contemplates the provision of a planetarium system in which a planetarium projector unit is supported for precessional rotation about its axis in a first ring which is pivotly supported for rolling about its diameter in a second ring, which in turn is rotatable about its axis for diurnal motion. The second ring is rotatably supported for diurnal rotation in a third ring which is rockably supported in gimbals by a vertical yoke for altitude alteration, the yoke being mounted on a base rotatable about a vertical axis. The improved planetarium is characterized by the projector unit being precessional rotatably mounted on a first ring which is pivotly rockably supported by a second ring which is rotatably supported by a concentric third ring for diurnal motion, the angle between the precessional and diurnal axes being adjusted by rocking the first ring about its pivots either manually or by a motor driven adjustment. The third ring is supported by a yoke for rocking about a horizontal axis for latitude alteration and the yoke is mounted on a base for rotation about a vertical axis. The various motions are effected by reversible motors through suitable speed reductions and drive couplings and a remotely controlled network is provided which is coupled to the projector and different motors through slip ring and brush arrangements for controlling the individual drive motors and projector light sources.

Since the axes of principal planets are inclined 0.degree. to 30.degree. with respect to the ecliptic pole, it is sufficient for educational purposes that the varying angles between the axis for diurnal motion and the axis for precession motion be limited to the range of 0.degree. to 40.degree..

In accordance with this invention, the change in the angle between the axis for diurnal motion and the axis for precession makes it possible to project the images of the celestial bodies as seen from a planet other than the earth such as Venus, Mercury or the like. As compared with conventional planetaria operated in combination with a computor, the present apparatus is extremely simple in construction and very easy to operate. Accordingly, it is most suitable for widespread educational uses with respect to cost and operation.

For the projection of the images of the stars as seen from representative planets, the angles between the foregoing two axes to be set for the respective cases may be indicated specifically or on a suitable scale. This will make the planetarium easier to operate when the angle is adjusted either manually or automatically by remote control. Even youngsters will then be able to operate the apparatus to its maximum capability. It is also easy to adjust the angle by watching the images of the heavens in converse manner.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a preferred embodiment of the present invention in simplied form;

FIG. 2 is a medial longitudinal sectional view showing in detail the drive mechanism for the projector diurnal and precessional rotation and the mechanism for adjusting the angle between the axes of these rotations, the diurnal and precessional axes being shown as coinciding for convenience of illustration; and

FIG. 3 is a diagramatic view of a control network for the different planetarium system motions.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings which illustrate a preferred embodiment of the present invention, the reference numeral 1 generally designates the axis for diurnal motion, 2 an axis for precessional motion, 3 an axis for latitude adjustment or alteration, and 4 a projector unit of known construction including at both its upper and lower ends various projectors for projecting images of the fixed stars, planets and the like. The projector unit 4 is so supported about the middle of its constricted body by a holding or first ring member 6 so as to be movable about the above-mentioned axes. A lateral support rod 5 serves to vary the angle .theta. between the axis 1 for diurnal motion and the axis 2 for precessional motion and has its axis passing through the intersection O of the three axes. The angle .theta. is adjusted as desired by turning the projector unit 4 about the lateral support rod 5 without causing any detrimental effect to or interfering with the motions of the projector unit 4 about the foregoing three axes.

The lateral support rod 5 diametrally extends from the holding ring member 6 for rotatably holding the projector unit 4 and supports the projector unit 4 in a rotary wheel or second ring 7 for diurnal motion by means of the holding ring member 6 and the lateral support rod 5.

The axis 3 for latitude alteration corresponds to opposite pivot rods which project radially outwardly from an outer frame or third ring 12 rotatably supporting the rotary wheel 7 for diurnal motion. The axis 3 for latitude alteration, as is known, is supported by housing 10' on a yoke 10 and operated by a means for effecting latitude adjustment or alteration stored in one of the housings. Indicated at 8 is a base for the yoke 10 supported by a rotary column 9 on a suitable pedestal.

The operation mechanism of the axes 1, 2 and 3 of the projection unit 4 indirectly supported on the yoke 10 as mentioned above is detailed below with reference to FIG. 2. The pivot rods defining the axis 3 for latitude alteration are fixed in a projection on the outer ring 12 by pins 11. The rotary wheel 7 for diurnal motion is adapted to smoothly rotate along the inner circumference of the outer ring 12 by a ball bearings 13. The rotary wheel 7 for diurnal motion is driven through a speed reduction unit by a reversible electric motor M1 fixed on the rotary wheel 7, by means of an internal gear 16 mounted circumferentially on the outer ring 12 and meshing with a gear 15 on the output shaft of the speed reduction unit 14 of motor M1. The motion of the rotary wheel 7 rotated by the motor M1 causes the diurnal motion of the projector unit 4, being rotated about the axis 1 for diurnal motion.

The electric currents for driving and controlling the rotary wheel 7 inside the outer ring 12 are transmitted to the motor M1 by an electric contact brush assembly 18 provided on the rotary wheel 7 and electric slip rings 17 provided circumferentially on the outer ring 12. That is, the annular slip ring assembly 17 is fixed circumferentially on the outer ring 12, and the brush assembly 18 on the rotary wheel 7 is rotated together with the rotary wheel 7 and receives the electric currents from the slip ring 17 to control the motor M1. The lateral support rod 5 connecting the rotary wheel 7 with the holding ring member 6 is an operation axis as an essential part of the present invention, as already mentioned. The opposite ends of the lateral support rod 5 are pivoted in the rotary wheel 7 by a pivot bearing 19, and the inner ends thereof are fixed by pins 23 in the holding ring member 6. A gear 21 fixed to one of the lateral support rods 5 is driven within a limited angle by a motor M2 fixed to the rotary wheel 7 through a speed reduction unit 20 and a pinion gear 22 meshing with the gear 21. The lateral support rod 5 thus varies the inclination of the axis 2 for precessional motion. The lateral support rod 5 does not completely rotate with respect to the rotary wheel 7, but inclines the projector unit 4 within a range of .+-. 30.degree. with respect to the axis 1 for diurnal motion. The electric current to the motor M2 is transmitted through electric slip rings 24 provided circumferentially on the lateral support rod 5 and an electric contact brush assembly 25 projecting from the rotary wheel 7.

On the other hand, precessional motion, that is, the rotation about the axis 2 for precessional motion of FIG. 1, is slowly effected by a motor M3 provided with a speed reduction unit 26. A gear 27 is fixed on the shaft of the speed reduction unit and meshes with a gear 28 fixed circumferentially on the axis 2. The motor M3 and the speed reduction unit 26 are fixed to the holding ring member 6. Thus, the rotation of the gear 28 causes the rotation of the tubular shaft 2' of the axis 2 for precessional motion, provided with the gear 28, and the shaft 2' is rotatably supported by a bearing 29 in the holding ring member 6 and is rotated by the motor M3 about a coaxial shaft 30 vertically penetrating the projector unit 4 and effects precessional motion. The transmission of the electric currents to the motor M3 is effected by the connection of electric slip rings 31 fixed circumferentially on the axis 2 with an electric contact brush assembly 32 provided on the holding ring member 6. The main axis 2' is provided at its top and bottom with flanges 33 and 34. As is known, for instance, the northern sky projection system is fitted to the flange 33, the southern sky projection system is fitted to the flange 34, thus providing a planetarium projection system. The axis 30 for annual motion of the projector unit 4 connects the southern and northern hemispheres or the upper and lower hemispheres in FIG. 1 and generally extends thereto through the hollow shaft or main axis 2'.

It is known in the art that a plurality of slip rings and contact brushes for power supply to the motors M1, M2 and M3 are provided for controlling the direction and speed of rotation of the motors.

Electric control circuits for the drives shown in FIG. 2 are described below with reference FIG. 3.

As shown in FIG. 3, a control console E comprises a control box including a dual 12 volt direct current source for energizing the motors for driving the projector unit 4 to effect its diurnal and precessional motions, an alternating current source (24V) for energizing the lamps for projecting the stars and the associated switches and switch contacts. Only the principal switches and switch contacts are shown in FIG. 3, but of course, all of the control switches for operating the projector unit 4 and projection are included in the console E.

Though not specifically shown in FIG. 2, a motor M4 for rotating the axis 3 for latitude alteration is drive coupled to an end of the axis and connected through a known double throw switch to the direct current source of the console E to drive motor M4 in either direction. A motor M5 for rotating the base 8 and a lamp L8 for the meridian projection are also connected to the power source of the console E through a double throw and single throw switch respectively. The minus poles of these loads are connected to a common line e of the console E.

As explained in connection with FIG. 2, all selective operations of the projector unit 4 are made by means of electric connection between the slip ring and brush assemblies provided in connection with each of the axes. So in the construction of the present system, the output of the power source of the console E, not shown in FIG. 2, is connected first through the first contact consisting of a slip ring 35 and a brush 36 provided about the axis 3; second at the contact between the slip ring 17 and the brush 18; third at the contact between the slip ring 25 and the brush 24; fourth at the contact between the slip ring 31 and the brush 32 and then transmitted to the respective loads. Thus, the first connection requires switch contacts (slip rings and brushes combined) enough for connecting the second and following loads, and the second connection, switch contacts (slip rings and brushes combined) enough for connecting the third and following loads. In FIG. 3, there are 12 combinations of the slip rings 35 and the brushes 36 which are like relay contacts connected to each of the second and following connections. They repeat the actuation of the circuits in response to selective switch control in the console E. At the second connection, eight contacts out of the 12 are connected to each of the third and following connections, but the remaining four are connected to the motor M1 for diurnal motion, the motor M2 for inclination alteration of the axis 2, a lamp L1 for equator projection (not shown in FIG. 2) and a lamp L2 for a pole point projection. The minus poles of these four contacts are connected to the common line e of the console E. Similarly, at the third connection, seven contacts out of the eight are connected to the fourth connection, but the remaining one, to the motor M3 for the axis 2 for precession motion. At the fourth connection, all the seven contacts are connected, though not shown in FIG. 2, to a lamp L3 for fixed star projection, a lamp L4 for moon projection, a lamp L5 for planet projection, a lamp L6 for sun projection, a lamp L7 for precession dial projection, a motor M6 for annual motion, etc. Moreover, rheostats, as shown in FIG. 3, are provided in some of the transmission circuits for controlling the intensities of respective lamps.

By an operator's selective operation of the switches of the console E of FIG. 3, the selected circuits are connected to the loads of the projector unit 4, and one of the elements M4, M5 and L8 at the first connection or the circuits of the elected loads at the second and following connections are closed, thus actuating all or any predetermined number of the selected loads at the same time, that is, the projector lamps, the drive motors in the desired directions, etc. Usually by operating the switches of the console E as above, the planetarium can be made to operate as desired, and besides the loads first actuated can be stopped and other loads operated.

While there has been described and illustrated a preferred embodiment of the present invention, it is apparent that numerous alterations, omissions and additions may be made without departing from the spirit thereof.

Claims

I claim:

1. A planetarium system having an adjustable angle between the diurnal motion and precessional motion axes comprising a planetarium projector unit, a ring first mount supporting said projector unit for precessional rotation about the axis thereof, a second mount, a third mount supporting said second mount for diurnal rotation about the axis thereof, a fourth mount supporting said third mount for rocking about a transverse axis of said third mount for adjusting the latitude orientation of said projector system, a base supporting said fourth mount and means including diametrically opposing rods radially extending between said first and second mounts for varying the angle between said precessional and diurnal axes.

2. The planetarium system of claim 1 wherein said ring first mount rotatably engages the mid-portion of said projector unit for precessional rotation about the axis thereof.

3. The planetarium system of claim 1 including an internally toothed gear mounted in and rotatable with said third ring and electric motor mounted on and rotatable with said second ring, a pinion gear driven by said motor and engaging said internally toothed gear, and means for selectively energizing said motor.

4. The planetarium system of claim 1 wherein a first of said rods is affixed to said first ring and said angle varying means includes a first gear mounted on said first rod, a motor mounted on and rotatable with said second ring, a gear driven by said motor and engaging said first gear, and means for selectively energizing said motor.

5. The planetarium system of claim 1 including a first gear rotatable with said projector about the precessional axis thereof, a motor mounted on said first ring, a gear driven by said motor and meshing with said first gear and means for selectively energizing said motor.

6. A planetarium system comprising a celestial body projector unit, first means for supporting said projector for rotation about a first medial axis thereof corresponding to precessional motion and for rotation about a second axis corresponding to diurnal motion and second means for adjusting the angle between said first and second axes about a third axis transverse to such first and second axis independently of the rotation of said projector unit about said first and second axis and including a pivot member coaxial with said third axis about which said projector unit is adjustable, each of said first, second and third axes being oblique to the vertical.

7. The system of claim 6 including third means for supporting said first and second means for angular variation about a fourth axis at an angle to said first, second and third axes to alter the latitude orientation of said system.

8. The planetarium system of claim 6 wherein said first means comprises a first mount supporting said projector for rotation about said first axis, and a second mount rotatable about said second axis, said pivot member extending between said first and second mounts.