Note: Descriptions are shown in the official language in which they were submitted.
'738
The present invention relates to a method of assembling
a motor drive, and more particularly to assembling motorized
drives Eor timing control devices, such as those relating to
timer/controllers employing small subEractional horse power
timing motors.
Small synchronous timing motors are typically used with
a speed reducer for driving timer/controllers or programmer
timers as they are sometimes referred to, employed for service
cycle control of domestic appliances such as clothes dryers,
washing machines and microwave cooking ovens.
In the design of appliances of the aforesaid type
employing a timing motor and speed reducer, the motor and speed
reducer subassembly drivingly engages a series of cam wheels for
sequentially actuating and deactuating electrical switches for
controlling various appliance electrical Eunctions.
In known programmer timers for appliances, heretofore
it has been the practice to provide a suitable common housing or
casing for the cam actuating mechanism and switches and to attach
the separate motor and speed reducer thereto with suitable
fastening techniques. Typically, the speed reducer mechanism is
assembled onto the switch housing and the motor is then fastened
thereto. In such known programmer timers, the switches and can
mechanism are usually assembled onto the opposite side of the
housing and suitable electrical terminals for the switches
provided for connecting the motor leads and switches thereto.
This type of programmer timer assembling arrangement has required
numerous positioning and assembly operations which have proven to
be costly in high volume manufacturing.
It has, there-Eore, long been desired to provide a
technique for assembling a motor and speed reducer to a cam
actuated switch programmer in a manner which permits rapid and
inexpensive modular assembly during manufacturing.
According to one aspect of the present invention there
is provided a method of assembling a motor gear drive with device
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to be driven, the method including the steps of providing a gear
box with an electrical terminal guide means and having a power
output shaft extending from one side thereof and a power input
shaft connec-tion provided on the opposite side thereof, and
providing a motor having a motor shaft extending therefrom and a
pair of electrical terminals extending therefrom in the direction
of the motor shaft. The method further includes the steps of
inserting the motor shaft into the gear box and engaging -the
motor shaft with the power input connection and inserting the
electrical terminals in the direction of the motor shaft into the
guide means all in a common direction, and inserting -the power
output shaft into engagement with a device to be driven and
simultaneously in a common direction therewith, inserting the
terminals into electrical power source connection of the device.
According to another aspect of the invention there is
provided a method of assembling a motor drive including the steps
of providing a motor speed reducer in a housing with an output
shaft engageable from one side thereof and extending electrical
connector means in the direction of the power shaft from the one
side of the housing. The method further includes the steps of
extending releasable fastening means from the housing means on
one side and inserting substantially simultaneously, in the
direction of the output shaft, the output shaft, the connector
means and the fastener means into a drive to be driven and
operatively engaging each of the means with the device for
transmitting electrical power to the motor means and mechanical
power to the device and securing the motor speed reducer to the
device.
Brief Description of the Drawings
Figure 1 is a side view in elevation of the power
transmission module of the present invention shown installed on a
device to be driven portions of which are broken away for
clarity;
Figure 2 is a bottom view of -the module of Figure 1
with the device to be driven omitted for clarity; and,
3~3
Figure 3 is a section view taken along section indicat-
ing lines 3-3 of figure 2.
Detailed Description
Referring now to Figures 1 and 2, the power transmis-
sion module is indicated generally at 10 with a motor 12
preferably of the synchronous permanent magnet type having a
mounting flange 14. The motor is received on a gear case or
housing 16 with the motor output shaft 18 received in the gear
case in mechanical engagement with the input gear (not shown)
thereof. The motor flange 14 is retained against the gear case
by a suitable fastening expedient as, for example, heat deformed
plastic rivets 20 received through the flange 14.
The side 22 of the gear case opposite the motor has
extending therefrom an output pinion 24 for driving engagement
with the device to be driven, indicated
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generally at 30, which has a surface 26 upon which the
gear case surface 22 is mounted in contact therewith.
The gear case 16 has a terminal guide lug 28 extending
therefrom and disposed adjacent the surface 22 and has a
pair of apertures 32 formed therethrough.
The motor 12 has a pair of electrical terminals
34, 36 extending out~ardly and do~nwardly therefrom.
Each of the terminals is received, respectively, thro~gh
one of the apertures 32 and extends outwardly therefrom
generally at right angles to the side 22 of the gear
case. The portion of the terminals between the lug 28
and the motor 12 is preferably provided with suitable
insulation.
R~ferring no~- to fig~re 3, the lug 28 is sho~n
in enlarged cross section, wherein the guide pin portion
3~ formed preferably integrally therewith and extending
oownwardly therefrom is clearly illustrated. The guide
pin portion 38 engages a corresponding guiàe hole 39
formed in the device 30 for aligning and positioning the
gear case 16 against the surface 26 of the device 30.
The electrical terminals 34, 36 each have
barbs, indicated respectively, at 40, 42 provided
thereon for engaging the wall of one of the holes 32 for
resisting removal from the direction of insertion, or
push loads directed upwardly on the ends of the pin, as
shown in figure 3.
Referring to figures 1 and 2, the~fastening
means for the module 10 is illustrated in the form of a
plurality of barbed prongs disposed in sets indicated
generally at 44, 46 disposed on opposite sides of the
gear case 16. Each set of prongs 44, 46 preferably
comprises a plurality of barbed prongs extending from
the side wall of the gear case downwardly in a direction
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generally parallel to the axis of pinion 24. With
reference to fi~ure 1, the set 44 of barbed prongs
comprises three prongs extending in generally spaced
parallel relationship with barbed tips 4B provided
thereon for snap locking engagement with the wall of
device 30 when the barbs are received in a hole 50
provided in the surface 26 of the device to be driven.
It will be understood that, for assembly, the
module 10 is positioned over the surface 26 of the
device 30 to be driven, pinion 24 is inserted to a
suitable clearance hole 52 provided in the aevice to be
driven, simultaneously the guide pin 3& is eng3ged in a
locating ho~e 3q and bar~c 44 and 4~ er.ter ho~es
provided tne.efor as shown typically at 50 in figure 1.
As the modul~ 10 is further moved to enga~ement with the
surface 26 of a device to be driven, barbeo PL ongs 44,
46 snap-locK to engage the undersurface 56 of the device
to be criven; a~d, terminals 34, 36 engage suitable
electrical rec-pt3cles shown as tubular connectors 58,
60 provioed ir, device 30. Tne receptacles 58, 60
function to su;-~ly electrical power to the motor 12.
Tne p ~-ion 24 provides mechanical power from
the module 10 t~ the device 30 to be driven by
engagement with the teeth of pinion 24. The module 10
is shown in th~ fully operationally installed position
in figure 1 wit~, the side 22 of gear case 16 in contact
with surface 2~ of a driver 30. It will be understood
that, if it is required to remove the dule 10 from
assembly with the device 30, it is necessary to have
access to the tips of the barbs 44, 4~ to compress the
barbs for release through the engagement hole s~ch as
hole 50.
~12~
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The present invention thus provides a plug-in
power transmission module for attachment to a device to
be driven such as a programmer/controller, and which may
be installed with a simple push-in snap-locking
engagement. The present invention provides simultaneous
connection of a driving gear pinion, motor electrical
connector terminals and snap locking fastening means for
retaining the module in its operating position.
Although the invention has hereinabove been
1~ described with reference to ~ne illustrated embodiment,
it will be understood that the invention is capable of
modification and variation by those of ordinary skill in
the art within the scope of the following claims.
