 |
Description  |
|
|
BACKGROUND OF THE INVENTION
U.S. Pat. No. Re. 25,805, which is assigned to the present assignee,
describes and claims an electric programmer of the same general type as
the programmer of the present invention. The programmer of the present
invention, like the programmer described in the patent, is comparatively
simple in its construction, and it is capable of being used in certain
non-critical type applications where extreme accuracy of a programming
operation is not required.
The programmer of the present invention is easy and convenient to use. An
important feature of the programmer is the provision of manual controls
which are directly accessible from the front of the programmer. These
controls are adjustable to set the time interval that each of the valves
or other instrumentalities, activated by the programmer of the invention,
is to remain in its active state.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the programmer of the invention with the
cover in place;
FIG. 2 is a front elevational view of the programmer of FIG. 1, with the
cover removed to reveal the internal operating components of the
programmer;
FIG. 3 is a side view of the programmer of FIG. 2, taken essentially along
the line 3--3 of FIG. 2;
FIG. 4 is a perspective view of a part employed in the programmer of FIGS.
1 through 3;
FIG. 5 is a sectional view taken along the line 5--5 of FIG. 3;
FIG. 6 is a partial section taken along the line 6--6 of FIG. 5;
FIG. 7 is a sectional view taken along the line 7--7 of FIG. 3;
FIG. 8 is a sectional view taken along the line 8--8 of FIG. 3;
FIG. 9 is a schematic wiring diagram showing the electrical connections
within the programmer; and
FIG. 10 is a fragmentary perspective representation of certain details of
the programmer.
DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT
The programmer of the invention is designated 10 in FIG. 1, and it includes
a housing 12, and a cover 13 hinged to the housing. The cover is held in a
closed condition with respect to the housing by an appropriate latch 14.
As shown in FIG. 2, a mounting plate 16 is supported within the housing 12
which, in turn, supports a conventional type of clock motor 18 (FIG. 3),
from which projects a shaft 20 on which is mounted a small gear 22. Gear
22 drives a second larger gear 24 which is mounted on shaft 26, the shaft
26 being supported by the mounting plate 16. During operation of the
mechanism, the clock motor 18 drives a clutch and dial assembly (to be
described) around shaft 26, through its drive shaft 20, and through gears
22 and 24.
A conventional clutch 28 is rotatably mounted on shaft 26. The clutch
carries a disc 30 in such a manner that the disc 30 is normally rotated by
the motor 18 in a counterclockwise direction as it is viewed in FIG. 2.
The clutch 28 permits disc 30 to be rotated by hand in a counterclockwise
direction, as viewed in FIG. 2, so as to permit the disc to be set to any
desired time position when the programmer 10 is being installed or
adjusted.
From an examination of FIG. 2, it will be seen that disc 30 carries a
plurality of indicia corresponding to the conventional hour markings on a
24-hour clock, and that a small pointer 32 is printed upon a circuit
selector control (to be described) so as to facilitate the setting of the
disc 30 to any desired angular position with respect to the hour markings
on its face. The disc 30 is provided with a plurality of equi-spaced holes
34 located around its periphery. These holes 34 correspond in spacing to
various desired time periods with respect to the hour markings on the disc
30. The holes 34 are designed so that a segmental gear 36, as illustrated
in FIG. 4 of the drawings, may be mounted on the disc 30 at any desired
location around its periphery.
The segmental gear 36 includes annular projections 38 which are adapted to
be located on the under surface of disc 30 and to fit within the
corresponding holes 34. The annular projections are internally threaded to
receive screws 42 (FIG. 2) which serve to mount the segmental gear 36 on
the disc 30 at the desired angular position, in order to hold the
segmental gear 36 securely on disc 30, so that it is rotated with disc 30.
The segmental gear 36 may be made any length desired so as to correspond
to a given time period. Furthermore, if desired, several additional
segmental gears (not shown) corresponding to the segmental gear 36 may be
mounted upon the disc 30 at other angular positions.
A framework 44 is attached to the rear side of plate 16 adjacent to the
motor 18 (FIG. 3). This framework 44 rotatably supports a programmer shaft
46, on which is mounted gear 48. Gear 48 is adapted to be engaged by the
segmental gear 36 during rotation of the disc 30 so as to cause rotation
of the shaft 46. Preferably the segmental gear 36 is proportioned as to
dimensions with respect to gear 48 so that gear 48 is turned one complete
revolution each time it is engaged by the segmental gear 36.
The shaft 46 carries disc 50 which, in turn, carries a plurality of
individual shafts 51. Each shaft 51 (FIG. 6) is rotatably mounted on disc
50, and each carries an eccentric pin 52 at its inner extremity, as shown
in FIGS. 5 and 6. Each shaft 51 is held within disc 50 by a serrated
retaining ring 53. Each of the shafts 51 is supported in the disc 50 by a
detent arrangement, and each has a head 51A (FIG. 8) which may be turned
by a screwdriver to any desired angular position, so as to set its
eccentric pin 52 at a corresponding angular position.
The framework 44 also carries a small snap-action switch 54 of conventional
design capable of making and breaking a conventional alternating or direct
current circuit (FIG. 7). The switch 54 is operated by a screw 55 which is
threaded into one end of an angular switch actuator arm 58. Arm 58 is
rotatably supported on the frame 44 by a pivot pin 57, and the arm is
spring-biased in a clockwise direction in FIG. 7 by an appropriate coil
spring 59 (FIG. 8) which is coiled around pivot pin 57. One end of the
coil spring 59 engages a shoulder 58B on actuator arm 58, and the other
end of the coil spring engages a post 63. The actuator arm 58 is integral
with an annular member 61.
The actuator 58 is positioned so that in the "off" position of switch 54
its other end rests between two of the eccentric pins 52. However, as the
shaft 46 is turned by the segmental gear 36, the pins 52 will engage a
projection 58A on the actuator 58 and will cause the actuator to turn
against the bias of spring 59, in a counterclockwise direction in FIG. 7.
As the shaft 46 continues to turn, the actuator arm 58 moves screw 55 away
from the switch 54 so that at a given predetermined point the switch 54
closes. By turning the individual eccentric shafts 51 (FIG. 6) it is
possible to vary the duration of the time interval when the switch 54 is
on or off, for each actuation of the switch by the different eccentric
pins 52, as the disc 50 is turned by the arcuate segmental gear 36.
As shown in FIG. 2, the individual shafts 51 are easily accessible from the
front of the instrument, and each may be set to a desired angular setting
by a simple screwdriver adjustment. The portion of the front face of disc
50 adjacent each of the shafts 51 may be suitably calibrated, so that the
shafts may be set to establish individual activation times of the circuits
controlled thereby for intervals, for example, extending from five to
thirty minutes, for each valve.
The shaft 46 also carries a rotatable switch wafer 60 which serves as a
distribution switch. The wafer 60 supports a rotatable wiper contact disc
64 which is turned by the shaft 46, and which is formed of appropriate
metal. The wiper contact disc 64 serves to complete an electric circuit
between a common switch contact 65 and a plurality of further contacts 66,
on a selective basis as the disc 64 is rotated.
The programmer 10 also includes a star wheel 78 (FIG. 2) which is mounted
on a shaft 80 which is rotatably secured by a bearing 82 to the plate 16.
Star wheel 78 is engaged by a spring-loaded pawl arm 79, so that the star
wheel may be detented from one angular position to the next. The star
wheel 78 is adapted to be rotated a fraction of a turn one each time disc
30 is rotated by engagement with a pin 84 secured to the underside of
segmental gear 36 (FIGS. 3 and 4). As disc 30 turns in a counter-clockwise
direction, pin 84 is moved down against pawl 79 in FIG. 3 causing the pawl
to turn down into the plane of the drawing against the tension of its
spring 81, so as to turn the star wheel 78 from one angular position to
the next. Pin 84 then slides over the end of the pawl and the pawl springs
back to its original position. The star wheel 78 may carry one or more
dependent pins 86 which are adapted to engage an actuating arm 88 of a
switch 90 of a conventional design, the switch being mounted on plate 16.
The plate 16 also mounts a switch 92 which is used in controlling the
operation of the programmer.
The switch 92 may be switched to a central "off" position in which the
operating circuits of the programmer are de-activated, although the clock
motor 18 continues to turn the disc 30. This setting of the switch 92 is
appropriate, for example, for a rainy day. The switch 92 may be set to
"automatic" for normal operation of the programmer. The switch may also be
set to "manual" which permits the circuit selector disc 50 to be turned
manually to activate any one of the circuits, merely by manually turning
gear 48, when it is not engaged by the segmental gear 36.
As shown by the wiring diagram of FIG. 9, the programmer includes a
terminal board 98. The circuit is supplied, for example, with 24-volts, 60
cycle alternating current by line connections to the two terminals
designated L1 and L2. These terminals are connected to the clock motor 18
through a circuit breaker 94 which may be reset by a reset button 95 (FIG.
2). The terminal L2 is also connected to the common contact of the switch
92. The manual contact of switch 92 is connected to the movable contact 65
of the wafer switch 60 and through a pilot light 93 to the terminal L1.
The contacts 66 of switch 60 are connected to respective terminals 1-6 on
the terminal strip 98. The terminal L1 is also connected to a common
terminal C. The various electric operated valves of the sprinkler system
in which the programmer is incorporated are connected between the common
terminal C and respective ones of the terminals 1-6.
It will be appreciated that when switch 92 is set to "manual" (M), the
pilot light 93 will be energized, and the movable contact 65 of wafer
switch 60 may be moved manually to any one of the contacts 66 of the wafer
switch to complete a circuit to the electric valve connected to a
corresponding one of the terminals 1-6. The particular valve will then
remain energized until the movable contact 65 is moved off the
corresponding switch contacts 66.
For automatic operation, the switch 92 is set to "automatic" (A). Then,
whenever the segmental gear 36 on disc 30 engages the circuit selector,
the movable contact 65 is moved successively from one contact 66 to
another, so that the various electric valves connected to terminals 1-6
may be successively activated. In each instance, the valves remain
activated for as long as switch 54 is closed, and this interval for each
electrically operated valve, is controlled by rotating the respective
shafts 51. However, the corresponding electrically operated valves are
energized only if the skip-a-day switch 90 is closed by a projection 86 on
the star wheel 78. Therefore, on any day in which it is desired that the
valves are not to be energized, the projection 86 is removed from the star
wheel for that particular day.
It wll be appreciated, of course, that although a particular embodiment of
the invention has been shown and described, modifications may be made. It
is intended in the claims to cover the modifications which come within the
true spirit and scope of the invention.
* * * * *
|
|
 |
|
 |
Description |
|
