US3609265A

US3609265A - Dual-actuated switch-operating mechanism

Info

Publication number: US3609265A
Application number: US49665A
Authority: US
Inventors: Siegfried Garbe; Joseph F Oles
Original assignee: Hoover Co
Current assignee: Hoover Co
Priority date: 1970-06-25
Filing date: 1970-06-25
Publication date: 1971-09-28
Anticipated expiration: 1988-09-28
Also published as: CA924362A; GB1358077A

Abstract

This invention in the preferred form relates to a dryer door switch-operating mechanism which in major part comprises a single-operation member adapted for both axial and rotary motion. Operation of the member requires both motions and in sequential order of first axial motion caused by closing of the door and then rotary motion created by manual reset to close the switch.

Description

United States Patent Inventors Appl. No. Filed Patented Assignee DUAL-ACTUATED SWITCH-OPERATING MECHANISM 5 Claims, 10 Drawing Figs.

U.S. Cl 200/6l.62,

200/4 Int. Cl H01h 3/16 Field of Search ZOO/61.62,

References Cited UNITED STATES PATENTS 2,734,281 2/1956 Kauffmann 34/87 3,149,212 9/1964 Smith......... ZOO/61.7

3,539,736 11/1970 Naimer.... 200 4 3,134,862 5/1964 Nelson 200/4 FOREIGN-PATENTS 867,129 5/1961 GreatBritain zoo/61.7

Primary Examiner-David Smith, Jr. Assistant Examiner-M. Ginsburg Attorneys-Alfred G. Gross and James A. Wanner ABSTRACT: This invention in the preferred form relates to a dryer door switch-operating mechanism which in major part comprises a single-operation member adapted for both axial and rotary motion. Operation of the member requires both motions and in sequential order of first axial motion caused by closing of the door and then rotary motioncreated by manual 1,958,123 5/1934 Barretetal. 210/72 reset to close the switch.

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01 E mum vww 8m DUAL-ACTUATEI) SWITCH-OPERATING MECHANISM BACKGROUND OF THE INVENTION An object of the present invention is to provide a switch mechanism which requires two separate and sequential operations to operate a single switch. One of these operations could be conducted by closing a door and the second of these operations could be manual, generally in such form as a pushbutton.

Another object of the present invention is to provide such a switch operation mechanism which is provided with relatively few operational members which are simplified, easy to manufacture and form a compact structure.

One primary application of such a switch operation mechanism is a domestic laundry appliance such as a clothes dryer wherein operation of the clothes dryer is available only after the dryer door is closed and a further operation of pushing a manual reset button. These two operations in combination and in this sequential order close a single switch which activates a control system for the clothes dryer.

A further object of this invention is that the switch mechanism operates to open or deactivate the switch upon a single operation, namely opening the door. After opening the door the switch will only be reactivated by both closing the door and pushing the manual reset in sequential order.

A further object of the invention is that the switch is operated by a single-operation member, the operation member being capable of both an axial and a rotary motion. Furthermore, in the preferred form the axial motion is caused by one operation, such as the door closing, while the rotary motion is caused by a second operation, such as by pushing a manual reset.

Such a switch-operating mechanism is particularly useful as a safety start mechanism for a domestic appliance such as a clothes dryer which has sufficient interior volume so as to be enticing to small children or pets. The activation of a control circuit with the switch mechanism of the present invention cannot occur solely upon closing of the door but requires both closing the door and operation of a manual reset. Operation cannot occur by operation of the manual reset and then closing the door. Thus the machine cannot be operated by a small child entrapped in the interior since activation requires operation of the manual reset which would in turn require opening the door to reach the manual reset.

Shown and described below are several forms of preferred embodiments practicing the present invention of a simplified switch operation mechanism.

DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a domestic appliance, such as a clothes dryer, incorporating the present invention.

FIG. 2 is an enlarged fragmentary sectional view along line 2-2 of FIG. I of one form of the invention.

FIG. 3 is an enlarged elevational view of the switch-operating mechanism of a second modification as viewed from the interior of the cabinet.

FIG. 4 is a fragmentary sectional view of the switch-operating mechanism of FIG. 3 taken along the line 4-4.

FIG. 5 is a side elevational view of the operation member of the switch-operating mechanism of FIGS. 3 and 4.

FIG. 6 is an end view ofthe operation member of FIG. 5.

FIG. 7 is an elevational view similar to FIG. 3 but of a third modification of the switch-operating mechanism.

FIG. 8 is a fragmentary sectional view of the switch-operating mechanism of FIG. 7 taken along the line 88.

FIG. 9 is a side elevational view of the operation member of FIGS. 7 and 8, and

FIG. 10 is an end view of the operation member of FIG. 9. Referring now to the drawings, FIG. 1 discloses a domestic appliance in the form ofa clothes dryer 2 in which the present invention can be utilized in its preferred form. The clothes dryer 2 is provided with an outer casing 4 and a control knob 6 which operates a timer mechanism not shown.

The dryer cabinet furthermore is provided with a front access opening 8 for loading and unloading clothes and normally closed by a door 10 having hinges l2. Mounted on the outer casing 4, adjacent the edge of the door 10 provided with hinges 12, is a manual reset button 14. The closing of the door 10 and the operation of the manual reset button provide two motions utilized to operate the switch mechanism described below.

FIG. 2 shows one preferred embodiment of the present invention of the door switch mechanism 15. This mechanism is provided with a microswitch 16 having a plunger 18. The microswitch 16 is of the type that the contacts, not shown, are closed when the plunger 18 is depressed and the contacts are spring biased open when no force is applied to plunger and thus the plunger is in an extended position. The microswitch I6 is supported on a mounting bracket 20 which is in turn supported off the front panel 22 of the cabinet 4 near the access opening. The plunger 18 is guided by an opening 19 in the mounting bracket.

The mounting bracket 20 also supports a switch operation member 24 so that the operation member 24 may reciprocate. Mounted with respect to the switch operation member 24 by means of a pin 26 is a door engagement member 28. The door engagement member 28 is mounted for axial reciprocation through openings 30 and 32 in the mounting bracket 20. The door engagement member 28 also extends through an opening 34 located in the front panel 22 at a position where the front panel 22 is recessed for location of the door 10 in a closed position. The door engagement member 28 is provided with a beveled edge 36 on the end protruding through the openings 32 and 34.

A leaf spring 38 is supported on one end by the mounting bracket. The other end of the leaf spring 38 engages the operation member 24 so as to act as a rotary positioning means by biasing the operation member 24 toward the front panel 22 about pin 26 and to also axially bias the operation member 24 toward the door engagement member 28. Since the door engagement member 28 is pin mounted with respect to the operation member 24 by means of pin 26, the door engagement member 28 will also be biased axially through the

openings

30, 32 and 34.

When the door 10 is open, the operation member 24 and the door engagement member 28 will be in a first

axial position

24 and 28 shown in FIG. 2 in phantom lines. Upon clos ing of the door 10, the edge of the door will engage the beveled edge 36 of the door engagement member 28 so as to axially slide the door engagement member 28 and the operation member 24 against the bias of the leaf spring 38 to a second axial position shown in solid lines in FIG. 2. It is noted that when the operation member 24 is in this second axial position, it has not yet engaged the plunger 18 of the microswitch 16.

The operation member 24 is free to pivot around the pin 26 against the bias of the leaf spring 38. The operation member 29 is provided with an elongated axial slot 42 through which a pin 44, carried by the manual reset button I4, is entrapped. The button 14 is reciprocated on an axis transverse to the axis of the operation member 24. The button 14 is mounted by a grommet 46 on the front panel 22 in a position with respect to the door 10 generally shown in FIG. 1.

Due to closing of the door the operation member 24 is in the second axial position which is also the first rotary position and shown by solid lines in FIG. 2. It is also noted that when the operation member 24 is in this position caused by the biasing of the leaf spring 38, and due to the pin 44, the manual reset button 14 extends outwardly beyond the grommet 46.

An axial force on the manual reset button 14 at this time causes the operation member 24 to be rotated against the bias of the leaf spring 38 to a second rotary position 24" shown also in phantom lines in FIG. 2. During this movement, switch actuation means or the cam face 48 of the operation member 24 engages the plunger 18 biasing the plunger 18 to a retracted position, thus closing the contact of the microswitch I6.

The can portion of the operation member 24 is also provided with a notch 50, which when the operation member 24 is fully rotated to the second rotary position 24", engages the plunger 18 holding the plunger 18 in the retracted position. This engagement also holds the operation member 24 in the second rotary position 24".

The closing of the contacts of microswitch l6 and the holding of these contacts in a closed position will activate a circuit, including the timer, for operation of the machine. This circuit will remain activated as long as the operation member 24 is held in the second rotary position 24". Upon ending of the dryer operation cycle the timer will deenergize the circuit but the microswitch 16 will still remain in the closed or activated position. When the door 10 is opened, either during or after the dryer operation cycle, the leaf spring 38 will bias both the operation member 24 and the door engagement member 28 axially toward the first axial position 24' and 28'.

Upon sufi'icient axial motion, the notch 50 will no longer engage the plunger 18 of the microswitch l6 and the leaf spring 38 will bias the operation member 24 from the second rotary position 24' toward the first rotary position shown in solid lines, which will in turn axially move the manual reset button 14 outwardly.

The motion of the operation member, when the door 10 is open, removes the force from the plunger 18, which opens the contacts of the switch 16 by means of a spring (not shown) generally located in the microswitch. The operating mechanism will again be in the phantom position 24' and 28 shown in FIG. 2.

It 24noted that operation of the manual reset button, when the door 10 is open, and thus the operation member 24 is in the first axial position 24', will not activate the microswitch 16 since this rotary motion will not bring the cam face 48 into engagement with the plunger 18.

It is, therefore, noted that both operations of closing the door 10 and pushing the manual reset button 14 must occur before activation of the microswitch 16. Furthermore, since the operation member will not be retained in its second rotary position 24", if the manual reset button 14 is operated prior to closing of the door 10, the closing of the door 10 must be prior to operation of the manual reset button 14 or at least simultaneous.

FIGS. 3 to 6 teach another preferred embodiment of the invention located basically in the same position in the clothes dryer of FIG. I as the first embodiment. The microswitch 16, including the plunger 18, is supported on a bracket 120. Located generally adjacent to the microswitch 16 is an operation member 124. This operation member 124 is mounted in the bracket I by bearings 13] and 133, for both an axial reciprocation motion and an annular rotary motion, by means of a door engagement member 128 and extension 129. The door engagement member 128 and extension 129 are integrally injection molded with the operation member 124 as shown in FIG. 5.

A left-hand coiled compression spring 138 is positioned around the extension 129 between a washer 139 and one end of the operation member 124. The compression spring 138 is used to axially bias the operation member 124 to a first axial position 124 against the bearing 133 as shown in phantom lines in FIG. 3.

The door 10 is hinged on the edge adjacent the location of the switch-operating mechanism. Therefore, closing of the door 10 will cause the edge ofthe door to apply a force against the door engagementmember 128 and thus bias the operation member 124 against the compression spring 138 to a second axial position shown in solid lines in FIG. 3.

The operation member 124 is provided with an axial cam surface 148, which upon axial movement, would engage the microswitch plunger 18 if the operation member 124 were in proper rotary alignment. The closing of the door, with movement of the operation member 124 between the first axial position and the second axial position, however, will not operate the plunger 18 since the correct rotary alignment has not yet been obtained. This axial motion will, however, provide correct axial alignment of the cam surface 148 with the plunger 18.

FIG. 4 shows the switch-operating mechanism of FIG. 3 in end elevation. The solid-line position of the operation member 124 in FIG. 4 corresponds to the second axial position or solid-line position of the operation member 124 shown in FIG. 3. This position is also the first rotary position of the operation member 124.

As in the embodiment taught in FIG. 2, a manual reset button 14 is mounted on the front panel 22 by means of a grommet 46. The manual reset button 14 is axially reciprocatable and is biased outwardly by a spring 147. The operation member 124 is provided with a button engagement portion 125 which extends radially through the axis of reciprocation of the manual reset button 14.

Operation of the manual reset button 14 against the spring 147 imparts a rotary movement of the operation member 124 through the button engagement portion 125 which rotates the operation member 124 from the first rotary position, shown in solid lines in FIG. 4, to a second rotary position 125" shown in phantom lines.

The operation member 124 is provided with a rotary cam face 149 perpendicular to the axial cam face 148. Since the cam portion or switch actuation means is in axial alignment with the plunger 18 of the microswitch 16, due to the closing of the door 10, the rotary motion imparted to the operation member 124 will cause the rotary cam face 149 to engage the plunger 18, thus closing the contacts of the microswitch 16. Friction between the plunger 18 and the top of the cam surface will keep the operation member 124 in the second rotary position when the manual reset button is released.

As seen in FIGS. 3, 5 and 6, the operation member 124 is further provided with a rotary positioning means or barrel cam portion 152 having a relatively thin portion 154 and a thick portion 156. A pin 158 is supported on the mounting bracket so as to engage the barrel cam portion 152 of the operation member 124.

When the operation member 124 is in the first axial position shown in phantom lines in FIG. 3, the pin 158 is within the thin portion 154 of the barrel cam 152. This pin, when the operation member 124 is in this first axial position, prevents rotary motion of the operation member 124 and thus retains the operation member 124 in the first rotary position.

When the operation member 124 is axially moved to the second axial position by the closing of the door 10, the pin 158 will now be located in the thick portion 156 of the barrel cam 152 so as to no longer prevent rotary motion of the operation member 124. Therefore, rotary motion can now be imparted to the operation member 124 by the manual reset button 14 to move the operation member 124 to the second rotary position. This guarantees that the axial motion of the closing of the dryer door 10 is prior to the rotary motion caused by operation of the manual reset button 14.

Furthermore, the thick portion 156 and thin portion 154 of the barrel cam 152 are connected by a bevel portion 160. This bevel portion 160, along with the pin I58, imparts a rotary motion from the second rotary position to the first rotary position to the operation member 124 when the door 10 is opened since the spring 138 axially biases the operation member 124 from the second axial position to the first axial position. This guarantees that the operation member 124 is always in the first rotary position when it is in the first axial position and thus the door 10 must be closed and the manual reset button again operated in order to restart the dryer. The barrel cam 152, along with the pin 158, thus guarantees the proper sequential order.

FIGS. 7 through 10 show a third preferred embodiment of the same general configuration as that shown in FIGS. 3 through 6, but using a different operation member 224. This embodiment again has a microswitch 16, including a plunger 18, mounted by a bracket 220 on the front panel 22. The operation member 224 is also mounted by the bracket 220 by means of

bearings

231 and 233.

The operation member 224 is also again provided with an integral door engagement member 28 and an extension 229. The spring 238, however, in this embodiment is both a compression spring and a torsion spring, one end of the spring resting on the button engagement member 224 so as to act as a rotary positioning means. The spring 238 also axially biases the operation member 224 to a first axial position 224' shown in phantom lines in FIG. 7.

The closing of the door again provides axial movement against the spring 238 to position the operation member 224 in a second axial position shown in solid lines in FIG. 7. As in the earlier embodiment shown in FIGS. 3 to 6, a manual reset button 14 engages button engagement portion 225 of the operation member 224 and is used to rotate the operation member 224 from a first rotary position shown in solid lines in FIG. 8 to a second rotary position 225" shown in phantom lines.

The operation member 224 is provided with a rotary cam face 249 which engages and depresses the plunger 18 of the microswitch 16 when the operation member 224 is in the second axial position and rotated from the first rotary position to the second rotary position.

Furthermore, the cam portion or switch actuation means is provided with a notch 250 which engages the plunger 18 to retain the operation member 224 in the second rotary position against the torsional bias of the spring 238. However, when the door 10 is open, the compression of the spring 238 will axially bias the operation member 224 to the first axial position, thus disengaging the notch 250 from the plunger 18 so as to permit torsional biasing of the spring 238 to move the operation member 224 back to the first rotary position.

The operation member 224, as taught in FIGS. 7 through 10, is also provided with an axial cam face 148 perpendicular to the rotary cam face 149. Thus, axial motion of the operation member 224 from the first axial position to the second axial position, if the operation member 224 is held in the second rotary position, will cause engagement of the axial cam face 148 of the plunger 18 to depress the plunger.

It is noted, however, that the manual reset button 14 must be continuously depressed during the axial motion of the operation member 224 from the first axial position to the second axial position in order for the axial cam face 148 to operate the plunger 18. In this respect this embodiment is similar to the first embodiment taught in that closing of the door must be either prior or simultaneous with the operation of the manual reset button. If the manual reset button was depressed first and then released, the torsion of the spring 238 would position the operation member 224 in the first rotary position so that the cam face 148 would not engage the plunger 18.

The axial cam face 148 may be removed from the operation member 224 so as to provide an operation similar to that of the second embodiment. With the axial cam face 148 removed, axial movement of the operation member 224 from the first axial position to the second axial position when in its second rotary position, will be impossible since the cam portion will engage the extended plunger 18 which will prevent further motion to the second axial position. Thus, with the axial cam face 148 removed, closing of the door must be prior and not simultaneous with the operation of the manual reset button 14.

The above three modifications teach several of the preferred forms of practicing the present invention which requires that two distinct motions of either simultaneous or sequential order are required to operate a single switch. However, other modifications may be made to the illustrated embodiments without departing from the scope of the invention. Therefore, it is intended that the appended claims include all such modifications and alternations.

We claim:

1. A switch-operating mechanism requiring two independent operation motions, said switch-operating mechanism comprising; a switch, an operation member mounted adjacent said switch for both axial and rotary movement, said operation member having both first and second axial positions and first and second rotary positions, cam means on said operation member in both axial and annular alignment with said switch when said operation member is in said second axial position and said second rotary position, axial biasing means axially biasing said operation member to said first axial position, rotary positioning means retaining said operation member in said first rotary position when said operation member is in said first axial position means rotating said operation member from said first rotary position to said second rotary position when said operation member is in said second axial position, and a separate means from said rotating means for axially moving said operation member from said first to said second axial position, whereby operation of said operating mechanism requires a first force to move said operation member against said biasing means from said first axial position to said second axial position and then a second independent force to move said operation member from said first rotary position to said second rotary position to position said cam means in said annular alignment with said switch so as to close said switch.

2. The switch operation mechanism of claim 1 wherein said rotary positioning means cooperates with said axial biasing means to move said operation member from said second ro tary position to said first rotary position when said operation member moves from said second axial position to said first axial position.

3. A door-switch-operating mechanism for a clothes dryer having a cabinet including a cabinet opening through which clothes are inserted and removed, a door mounted with respect to said cabinet and movable between a closed position and an open position so as to selectively cover said cabinet opening when in said closed position and uncover said cabinet opening when in said open position, said door-switch-operating mechanism comprising a switch, a switch operation member, manual reset means, and door engagement means, said switch operation member activating said switch when said door engagement means is operated by movement of said door to said closed position and said manual reset means is operated so as to further operate said switch-operating mechanism, said switch being deactivated when said door is moved to said open position, the improvement comprising;

said operation member being mounted for both axial and rotary movement adjacent said switch, switch actuation means on said operation member, biasing means axially biasing said operation member to a first axial position wherein said switch actuation means is out of axial alignment with said switch and whereby movement of said door to said closed position moves said door engagement means and thus axially moves said operation member against said biasing means to a second axial position so that said switch actuation means is in axial alignment with respect to said switch and operation of said manual reset means when said operation member is in said second axial alignment position rotatably moving said switch operation member from a first rotary position to a second rotary position bringing said switch actuation means into rotary alignment with said switch thereby actuating said switch.

4. The door-switch-operating mechanism of claim 3 wherein said switch actuation means includes cam means, and said operation member, said cam means, and said door engagement means are integrally molded.

5. The door-switch-operating mechanism of claim 4 including rotary positioning means for maintaining said operation member in said first rotary position when said operation member is in said first axial position and permitting rotary movement of said operation member from said first rotary position to said second rotary position when said operation member is in said second axial position, said rotary positioning means comprising barrel cam means on said operation member.

Claims

2. The switch operation mechanism of claim 1 wherein said rotary positioning means cooperates with said axial biasing means to move said operation member from said second rotary position to said first rotary position when said operation member moves from said second axial position to said first axial position.

3. A door-switch-operating mechanism for a clothes dryer having a cabinet including a cabinet opening through which clothes are inserted and removed, a door mounted with respect to said cabinet and movable between a closed position and an open position so as to selectively cover said cabinet opening when in said closed position and uncover said cabinet opening when in said open position, said door-switch-operating mechanism comprising a switch, a switch operation member, manual reset means, and door engagement means, said switch operation member activating said switch when said door engagement means is operated by movement of said door to said closed position and said manual reset means is operated so as to further operate said switch-operating mechanism, said switch being deactivated when said door is moved to said open position, the improvement comprising; said operation member being mounted for both axial and rotary movement adjacent said switch, switch actuatioN means on said operation member, biasing means axially biasing said operation member to a first axial position wherein said switch actuation means is out of axial alignment with said switch and whereby movement of said door to said closed position moves said door engagement means and thus axially moves said operation member against said biasing means to a second axial position so that said switch actuation means is in axial alignment with respect to said switch and operation of said manual reset means when said operation member is in said second axial alignment position rotatably moving said switch operation member from a first rotary position to a second rotary position bringing said switch actuation means into rotary alignment with said switch thereby actuating said switch.