U.S. patent number 3,602,015 [Application Number 04/807,712] was granted by the patent office on 1971-08-31 for electromechanical interlock for laundry apparatus.
This patent grant is currently assigned to Westinghouse Electric Corporation. Invention is credited to John D. Hughes.
United States Patent |
3,602,015 |
Hughes |
August 31, 1971 |
ELECTROMECHANICAL INTERLOCK FOR LAUNDRY APPARATUS
Abstract
Interlock for the door of a clothes washing machine or the like.
The interlock is characterized by the provision of a
solenoid-actuated door lock, which solenoid is operatively
connected to a source of electrical power by means of a condition
responsive structure and also by a manually operable switch.
Energization of the solenoid serves to unlatch the door lock to
thereby provide a "fail-safe" device, which can only be opened when
the machine is not operating and by actuation of the manual
operable switch.
Inventors: |
Hughes; John D. (Loudonville,
OH) |
Assignee: |
Westinghouse Electric
Corporation (Pittsburgh, PA)
|
Family
ID: |
25197018 |
Appl.
No.: |
04/807,712 |
Filed: |
March 17, 1969 |
Current U.S.
Class: |
68/12.26;
68/139 |
Current CPC
Class: |
D06F
37/42 (20130101) |
Current International
Class: |
D06F
37/00 (20060101); D06F 37/42 (20060101); D06f
033/02 (); D06f 039/14 () |
Field of
Search: |
;68/12,139
;134/57DL,58DL ;4/292 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Price; William I.
Claims
What is claimed is:
1. Door interlock for a clothes washing machine having an access
door to the washing apparatus and suitable circuitry including a
timer for controlling the operation thereof, said interlock
comprising:
a manually actuatable switch;
a timer-actuated switch;
movable means for normally locking said door when said door is in a
closed position;
solenoid means connected to said locking means for moving said
locking means to an unlocking position when said solenoid is
actuated; and,
a fluid pressure switch serially connected to said solenoid with
said manually actuable switch and said timer-actuated switch and
moved from an open to a closed position in response to the level of
the washing fluid within said machine being at least below said
access door.
2. The door interlock of claim 1 wherein said fluid pressure switch
is open whenever said washing machine contains washing fluid.
Description
BACKGROUND OF THE INVENTION
This invention relates, in general, to laundry apparatus and, more
particularly, to door lock structure therefor.
It is well known that commercial washing machines of the tumbler
type utilize water which exceeds the level of the machine opening.
This means that if the door is opened prematurely, a person could
be scalded by the extremely hot water. There are also other
hazardous conditions which exist, for example, during the water
extraction part of the cycle when accessibility to the interior of
the machine is prohibitive.
Accordingly, it is the general object of this invention to provide
a new and improved clothes washing machine.
It is a more particular object of this invention to provide, in a
clothes washing machine, an electromechanical door interlock, the
purpose of which is not frustrated by an electrical power
failure.
Another object of this invention is to provide a door lock for a
washing machine which cannot be unlatched during operation of the
machine or at preselected times during the operation of the
machine.
BRIEF SUMMARY OF THE INVENTION
Briefly, the above-cited objects are accomplished by the provision
of a lock having a latch and catch arrangement wherein the latch is
spring biased into a door locking position. A solenoid is provided
for overriding the spring through the pivoting of a lever in
response to energization of the solenoid. In order to provide a
safety feature which prevents unlatching of the lock at any time
during operation of the machine or during preselected times during
the operation thereof, a timer-actuated switch is provided which is
opened at the preselected times, consequently, the solenoid cannot
be energized. A pushbutton switch is also provided which switch
cooperates with the timer-actuated switch to permit energization of
the door lock solenoid, closure of both switches, simultaneously,
being required before the door can be opened.
In a modified form of the invention, a pressure-actuated switch is
combined in circuitry with the timer-actuated and pushbutton
switches such that the door unlock solenoid cannot be energized
while water remains in the machine, even though operation of the
machine has terminated.
Further objects and advantages of the present invention will become
more apparent when considered in view of the drawings and detailed
description forming a part hereof.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a clothes washing machine
representing the invention;
FIG. 2 is a plan view of a latch arrangement employed for locking
the door structure of the machine shown in FIG. 1;
FIG. 3 is a schematic of one form of interlock employed in the
machine illustrated in FIG. 1; and
FIG. 4 is a schematic of a modified form of the invention shown in
FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, especially FIG. 1, reference
character 10 designates generally a clothes washing machine of the
tumbler type (i.e. basket rotates about substantially horizontal
axis). While the present description will be confined to a machine
of this type, it will be appreciated that those machines which are
referred to as "top loading" may also employ the invention.
Furthermore, the invention could be utilized in clothes dryers. The
machine 10 comprises a body or shell 11 having attached thereto a
service panel 12 and a top panel 13.
The machine 10 is provided with a fabric conditioner dispenser (not
shown) which is accessible through a door 14 in the top panel 13. A
detergent dispenser (also not shown) is accessible through a door
16 also carried by the top panel 13. The operation of the machine,
being designed for use as a commercial unit, can only be varied
insofar as the water temperature is concerned. To this end, there
is provided an actuator knob 17. Other features which generally
characterize the machine 10, are a coin meter 18 and a coin vault
19.
A door structure 21 supported for pivotal movement by a front wall
22 of the shell 11 provides access to the interior of the clothes
basket (not shown). The door structure has a glass 23 mounted
centrally thereof for viewing the interior of the washing machine
during operation.
A door lock structure generally indicated at 24 (see FIG. 2)
comprises a catch member 26 carried on the inside of the door
structure 21. A latch housing 27 is mounted on the inside of the
front wall 22 adjacent the catch 26. The latch housing has a
transverse slot 28 which cooperates with a latch member 29 for
movement from left to right and vice versa, as viewed in FIG. 2.
The latch member 29 is operatively connected to a roll pin
structure 31 which, in turn, is attached to a link latch or lever
32 pivotally supported by the latch housing 27. The latch member 29
is normally biased, by means of a spring 33, into locking
engagement with the catch 26, that is, when the door structure 21
is in its closed position.
A solenoid 34 mounted on a bracket 36, carried by the front wall
22, is connected to the lever 32 by a spring 37. It will be
appreciated that upward movement (as viewed in FIG. 2) of a plunger
38 of the solenoid 34 will effect pivoting of the lever 32 such
that the latch will be moved out of engagement with the catch
26.
Energization of the solenoid 34 is accomplished, in accordance with
the embodiment shown in FIG. 3, through closure of a pushbutton
switch 39 and the closure of a timer-actuated switch 41. In the
preferred mode of operation, the switch 41 is adapted to be closed
by the timer only when the cycle of operation of the machine has
terminated. It should be apparent that the use of the spring 37
serves as a protective device which prevents the burning out of the
solenoid 34, should the lock structure 24 become stuck.
In the embodiment shown in FIG. 4, there is provided a pressure
switch 42 which is opened any time the machine contains water. In
view of the foregoing description it will now be apparent that
there has been provided an interlock for a clothes washing machine
which interlock comprises a manually engaged latch and catch
arrangement wherein the disengagement can only be accomplished
through energization of a door unlock solenoid which solenoid
requires the coincidence of at least three predetermined
conditions, namely, an inoperative machine, the machine drained of
water and the manual operation of a pushbutton switch.
Since numerous changes may be made in the above apparatus and
different embodiments may be made without departing from the spirit
thereof, it is intended that all matter contained in the foregoing
description or shown in the accompanying drawings, shall be
interpreted as illustrative and not in a limiting sense.
* * * * *