Motion sensor and detection system

A motion sensor comprises first and second housings comprised of electrically conductive material, first and second electrically conductive elements movably supported respectively in the first and second housings, and a joinder member for interconnection of the first and second housings, the joinder member being comprised of electrically insulative material and defining a passage permitting movement of the first and second electrically conductive means between the first and second housings responsively to orientation of the tag. The joinder member, the housings and the first and second electrically conductive elements are collectively dimensioned to provide for electrical conductivity between the first and second housings upon reorientation of the tag from a disposition wherein neither of the first and second electrically conductive elements are in registry with the joinder member. Detection circuitry is associated with the sensor to provide electrical output indication of the sensing of motion of parent structure on which the sensor and detection circuitry are disposed.

FIELD OF THE INVENTION 
This invention relates generally to motion detection and pertains more 
particularly to improved motion sensors and detection systems. 
BACKGROUND OF THE INVENTION 
In various instances, need exists for the detection of motion of electrical 
devices. For example, in certain types of portable, battery-powered 
apparatus, it is desirable to conserve battery power by maintaining the 
battery disconnected from the load circuitry of the apparatus during 
periods in which the apparatus is immobile and to reconnect the battery 
with its load circuitry when the apparatus equipment is moved. 
While various forms of motion detectors are known, from applicant's 
viewpoint, they do not sufficiently meet the current demands of industry 
in respects such as size, sensitivity and simplicity of structure. 
SUMMARY OF THE INVENTION 
The present invention has as its primary object the provision of improved 
motion sensing and detection apparatus. 
It is a more particular object of the invention to provide for enhanced 
battery life conservation in battery-powered, portable devices. 
In attaining the foregoing and other objects, the present invention 
provides a motion sensor comprising first and second housings comprised of 
electrically conductive material, first and second electrically conductive 
elements movably supported respectively in the first and second housings, 
and a joinder member for mechanical interconnection of the first and 
second housings, the joinder member being comprised of electrically 
insulative material to electrically isolate the housings from one another 
and defining a passage permitting movement of the first and second 
electrically conductive means between the first and second housings 
responsively to orientation of the sensor or apparatus carrying the same. 
The joinder member, the housings and the first and second electrically 
conductive elements are collectively dimensioned to provide for electrical 
conductivity between the first and second housings upon reorientation of 
the tag from a disposition wherein neither of the first and second 
electrically conductive elements is in registry with the joinder member to 
other disposition. 
The invention will also be seen to provide motion sensing and detecting 
apparatus, comprising: first and second housings comprised of electrically 
conductive material; first and second electrically conductive means 
movably supported respectively in the first and second housings, and 
joinder means for interconnection of the first and second housings, the 
joinder means being comprised of electrically insulative material and 
defining a passage permitting movement of the first and second 
electrically conductive means between the first and second housings 
responsively to orientation of the motion sensor, and detection circuitry 
having electrical connection with the first and second housings and 
responsive to the movement of the first and second electrically conductive 
means to provide output indication of motion of the apparatus. 
The foregoing and other objects and features of the invention will be 
further understood from the following detailed description of preferred 
embodiments thereof and from the drawings wherein like reference numerals 
identify like components and parts throughout.

DESCRIPTION OF THE PREFERRED EMBODIMENTS AND PRACTICES 
Referring now to FIGS. 1-3, motion sensor 24 will be seen to include first 
and second housings 32 and 34, each comprised of electrically conductive 
material and being preferably in the form of a hollow, cup-shaped device. 
First and second electrically conductive elements 36 and 38, which are 
desirably metal spheres, are disposed respectively in the first and second 
housings to be highly mobile therein. A joinder member 40 interconnects 
the first and second housings and is comprised of electrically insulative 
material, defining a central passage permitting movement of spheres 36 and 
38 between the first and second housings responsively to orientation of 
the tag. 
The joinder member, the housings and the first and second electrically 
conductive elements are collectively dimensioned, as discussed in detail 
below, to provide for electrical conductivity between the first and second 
housings upon reorientation of the tag from disposition wherein neither of 
spheres 36 and 38 are in registry with the joinder member. The latter 
disposition is seen in FIG. 3, which also shows member 40 to have an 
interior, circularly continuous rib 40a against which flanges 32a and 34a 
of housings 32 and 34 abut on assembly, the rib electrically insulating 
the housings from one another. As is also seen in FIGS. 2 and 3, joinder 
member 40 includes circularly extending, mutually spaced locking tabs, 
shown at 40b, 40c, 40d and 40e, which secure the assembly. 
Turning to FIG. 4, motion sensor is shown in a second disposition, wherein 
spheres 36 and 38 are in contiguous relation, sphere 38 having rolled into 
engagement with sphere 36, based on movement of the motion sensor. Sphere 
38 is thus in registry with rib 40a, and the sphere diameters and the 
dimension of rib 40a longitudinally of the movement passage are selected 
to insure that sphere 38 retains electrical engagement with housing 34 
when in engagement with sphere 36 and conversely for movement of sphere 36 
into engagement with sphere 38. This event gives rise to electrical 
continuity between conductor 28, connected to housing 34 and conductor 26 
connected to housing 32. The conductive path is thus from conductor 26, 
through housing 32, through spheres 36 and 38, through housing 34 and to 
conductor 28. 
As for the above noted collective dimensioning of the components of the 
motion sensor, reference is now made to the schematic showings of FIGS. 5 
and 6. The motion sensor is elongate, with central, longitudinal axis C. 
In the FIG. 5 showing, the electrically conductive elements are indicated 
as blocks 36a and 38a and various dimensions are indicated. Equal lengths 
Ll and L2 apply to the housings 32 and 34. Lengths L3 and L4 apply to 
blocks 36a and 38a and are shown as essentially equal to lengths Ll and 
L2. Length L5 is the dimension of rib 40a along axis C. Given the equality 
among Ll, L3 and L2, L4, the collective dimensioning of components in the 
FIG. 5 showing, for operativeness of the motion sensor, is simply that 
each of L3 and L4 exceed L5. This assures that, on motion to which the 
motion detection is sensitive, one or the other of blocks 36a and 38a will 
span rib 40a and yet retain electrical connection with its housing when 
engaging the other block. 
In the FIG. 6 showing, lengths L3', and L4', of blocks 36b and 38b are 
shown as equal and less than lengths L1 and L2 as is the case with the 
spherical elements of the preferred embodiment discussed above. Here, for 
operativeness of the motion sensor, the sum of lengths L3', and L4', need 
exceed the sum of lengths L1 and L5 and also need exceed the sum of 
lengths L2 and L5. 
Turning to FIGS. 7 and 8, system 50 is used to detect the movement of the 
electrically conductive elements sensed by the motion sensor. Housing 32 
of the motion sensor is electrically connected by line 26 to the negative 
terminal of battery B, which terminal is the ground reference in the 
system. Housing 34 is electrically connected by line 28 to input line 52 
of system 50. When the elements 36 and 38 are making contact with one 
another, input line 52 is electrically connected to the negative terminal 
of the battery. When the elements are separated, the line 52 voltage level 
is pulled up to the battery voltage V+through resistor 54, the resistance 
value of which is very large so that the current through the resistor is 
minimized when line 52 is grounded. 
When the motion sensor is at rest, elements 36 and 38 will be stationary 
and will either be in contact or be separated from one another. Therefore, 
input line 52 will be at a constant voltage level (ground or V+). When 
there is movement, the elements will be in random motion, sometimes making 
contact and sometimes separated. This will cause line 52 to toggle between 
V+and ground. The system includes for motion detection a transition 
detector 56, a latch 58, a timer 60 and an analog switch 62. The system is 
furnished with clock pulses over line 64 from a suitable clock pulse 
generator or crystal (not shown). 
Transition detector 56 is operative to sense a change in voltage level on 
input line 52, either from ground to V+or from V+to ground. When there is 
no motion, the inputs to exclusive OR (XOR) gate 66 will be at opposite 
logic levels. If the upper input is high (logic 1), the lower input will 
be low (logic 0) and vice versa, since the lower input is connected to the 
upper input by an inverter 68. The following truth table applies. 
______________________________________ 
UPPER LOWER 
STATE INPUT INPUT OUTPUT 
______________________________________ 
1 0 0 0 
2 0 1 1 
3 1 0 1 
4 1 1 0 
______________________________________ 
From the table, it can be seen that both states 2 and 3 will cause the 
detector 56 output to be high. When line 52 changes voltage level, the 
inputs to gate 66 will be at the same logic level for a short period of 
time (states 1 or 4). While the inputs are in this state, the output of 
detector 56 will go low. This creates a pulse on output line 70 of the 
detector on both positive and negative transitions of line 52. The pulse 
width is determined by the propagation delay of inverter 68 and the charge 
time of capacitor 72. The timing of this pulse is shown in FIG. 8, parts 
(a) and (b). 
The detector 56 output is applied over lines 74 and 76 respectively to 
latch 58 and timer 60. When the detector output goes low, as is seen in 
part (b) of FIG. 8, it resets the timer, causing the output of the timer 
on line 84 to go low for a preselected time period T, as is shown in part 
(c) of FIG. 8. The detector output also provides a clock signal on line 74 
for latch 58. On the positive edge of the pulse, the output of the latch 
will go high, as is seen in part (d) of FIG. 8. The output of the latch 
provides a control signal on line 78 for analog switch (SW) 62. When the 
latch 58 output goes high, analog switch 62 is enabled. This event passes 
the clock input on line 64 through the switch to the timer over line 80 
and to other circuitry (not shown) over line 82. This event is seen in 
part (e) of FIG. 8. 
Once the clock input is applied to the timer, the timer begins to count. If 
another pulse is thereafter generated by transition detector 56, the timer 
will be reset and will restart its count, as is the case in the showing of 
FIG. 8. If there is no motion for the time period set, the timer will 
overflow, causing the output of the timer to go high. This resets the 
latch and causes the output of the latch to go low. Once the output of the 
latch goes low, the analog switch is disabled and this event disconnects 
the clock input from the timer and such other circuitry. Such other 
circuitry, which is connected to battery B, would fulfill the function of 
the apparatus on which the motion sensor and detection system are 
disposed. Where the other circuitry is CMOS, its current consumption is 
directly proportional to the clock frequency on line 82. The invention, by 
disabling the clock, substantially reduces battery loading. A 
substantially greater life expectancy is thus afforded by apparatus of the 
invention. 
Evidently, where there is the condition of continuing resetting of the 
timer, motion being sustained, the battery is loaded by the other 
circuitry and the apparatus associated with the motion sensor is thereby 
fully operative. 
The invention will thus be seen to provide motion sensing and detecting 
apparatus, comprising: first and second housings comprised of electrically 
conductive material; first and second electrically conductive means 
movably supported respectively in the first and second housings, and 
joinder means for interconnection of the first and second housings, the 
joinder means being comprised of electrically insulative material and 
defining a passage permitting movement of the first and second 
electrically conductive means between the first and second housings 
responsively to orientation of the motion sensor, and detection circuitry 
having electrical connection with the first and second housings and 
responsive to the movement of the first and second electrically conductive 
means to provide output indication of motion of the apparatus. 
The invention further includes parent structure to which the apparatus is 
affixed, the parent structure including an electrical power source 
connected to the apparatus and to other circuitry of the parent structure, 
the apparatus being operative to effect operational loading of the power 
supply by the other circuitry on the detection circuitry output indication 
and to lessen electrical power communication from the power source to the 
other circuitry in the absence of the detection circuitry output 
indication. 
Where the other circuitry is of CMOS character, the detection circuitry 
functions to discontinue supply of clock pulses applied thereto to the 
other circuitry. The detection circuitry includes a detector unit 
connected to one of the housings to selectively generate an output signal 
indicative of motion of the apparatus, a switch operative on such 
detection means output signal generation to conduct clock pulses 
therethrough to the other circuitry, and a timer advanced by the clock 
pulses conducted through the switch. The timer has a predetermined pulse 
count capacity and is connected to the detection unit to receive the 
detection unit output signal and to thereby be reset to zero count. The 
timer is operative to render the switch inoperative to conduct clock 
pulses therethrough on counting pulses in excess of the predetermined 
count capacity thereof. A latch is connected to the detection unit to 
receive the detection unit output signal, the latch thereupon rendering 
the switch operative to conduct the clock pulses therethrough. The latch 
is connected to the timer to receive indication therefrom of the counting 
of pulses in excess of the predetermined count capacity thereof, the latch 
being connected to the switch to render the switch inoperative to conduct 
the clock pulses therethrough upon receiving such excess count indication 
from the timer. 
As contrasted with unsealed sensors of the prior art with attendant ingress 
of contaminants, joinder member 40 is configured as shown as a snap ring 
tightly engaging the cup housing members. 
Further, a high degree of mobility is afforded spheres 36 and 38 in the 
passage collectively defined by the housings and the joinder member. 
Various changes may evidently be introduced in the foregoing structure 
without departing from the invention. For example, the number of spheres 
employed may be of number exceeding the two spheres in the preferred 
embodiment. Thus, the particularly described and preferred embodiment is 
intended to be illustrative and not limiting of the invention. The true 
spirit and scope of the intention is set forth in the appended claims.