Laundry Machine Door Assembly

This application is directed to laundry washer and dryer door assemblies.

Laundry machines, particularly washers and dryers (and combination washer/dryers), are often configured with a drum access door on the front face of the machine. Such doors typically are designed to react to internal loads generated by normal operation, but release when the load exceeds a predetermined threshold. In particular, the laundry load can contact the door as the drum rotates during operation of the machine, and the door must resist forces caused by such contact to prevent the laundry from forcing the door open as the machine operates. However, a person such as a playing child might climb into the laundry machine drum, in which case the person preferably can push the door open from the inside to escape the drum. Thus, a laundry machine door might be designed to resist relatively low loads (e.g., 9 pounds or less) caused by normal operation, but release upon experiencing a higher load (e.g., 15 pounds or more) as might be generated in an emergency situation.

The design of a laundry machine door is further complicated if one takes into consideration the desire to make the door operable from the outside by persons who are not able to generate much force to open or close the door. For example, the Americans With Disabilities Act (ADA) suggests that a door should be openable from the outside by applying less than 5 pounds of force. It has been found that this additional functionality can be difficult to obtain, and a door that meets the internal load requirements described above oftentimes is not able to satisfy the ADA's suggested opening force threshold.

This description of the background is provided to assist with an understanding of the following explanations of exemplary embodiments, and is not an admission that any or all of this background information is necessarily prior art.

In a first aspect, there is provided a laundry machine having a housing having an access opening, a drum mounted within the housing and configured to rotate about a generally horizontal rotation axis, the drum including an open end located along the rotation axis and facing the access opening, a door rotatably connected to the housing adjacent to the access opening, the door being movable between a closed door position in which the door closes the access opening, and an open door position in which the door does not close the access opening, and a door latch assembly. The door latch assembly has: a bolt movable between a first bolt position and a second bolt position, wherein the first bolt position is located on a first travel path defined by movement of the door between the closed door position and the open door position, and the second bolt position is located on a second travel path defined by movement of the door between the closed door position and the open door position, a bolt handle having a grip portion that is accessible when the door is in the closed door position, the bolt handle being operatively connected to the bolt and configured to move the bolt from the first bolt position to the second bolt position, and a catch mounted within the first travel path and not within the second travel path, the catch being configured to engage the bolt when the door is in the closed door position and the bolt is in the first bolt position, wherein the catch and bolt are is configured to exert an opening force opposing movement of the bolt along the first travel path upon movement of the door from the closed door position towards the open door position. The bolt and the bolt handle are mounted to one of the door and the housing, and the catch is mounted to the other of the door and the housing.

The laundry machine may have a forced-air drying system.

The bolt may be mounted to move along a linear path between the first bolt position and the second bolt position.

The linear path may extend from the first bolt position towards a rotation axis of the door.

The bolt may be integrally formed with the bolt handle.

The bolt may be connected to the bolt handle by an intermediate linkage.

The bolt may be mounted to the door to move along a semicircular path about a bolt rotation axis between the first bolt position and the second bolt position.

The bolt rotation axis may be parallel to a rotation axis of the door.

The catch may be configured to exert a closing force opposing movement of the bolt along the first travel path upon movement of the door from the open door position to the closed door position.

The closing force may be equal to the opening force.

The bolt may be operatively connected to the door or the housing by a resilient member configured to exert an unlatching force opposing movement of the bolt from the first bolt position to the second bolt position.

The resilient member may include a spring positioned between the door or the housing and at least one of the bolt and the bolt handle.

The spring may be integrally formed with the bolt.

The unlatching force may be less than the opening force.

The unlatching force may be less than 5 pounds force, and the opening force may be between 9 pounds force and 15 pounds force.

The bolt may have an entry face directed towards the closed door position and an exit face directed towards the open door position, and the catch may have opposed leaf springs configured to be spread apart by the entry face upon movement of the door approaching the door closed position with the bolt in the first bolt position, and to move together to at least partially surround the exit face upon the door reaching the closed position with the bolt in the first bolt position.

The entry face may have an entry wedge that tapers towards the closed door position to an entry wedge tip, and the exit face may have an exit wedge that tapers towards the open door position to an exit wedge tip.

The entry wedge may taper at a first angle, the exit wedge may taper at a second angle, with the first angle being equal to the second angle.

illustrate a laundry machineaccording to exemplary embodiments. The laundry machine includes a housingthat defines an access opening, and a drummounted within the housing. The drumis mounted to the housingby pulleys, rollers, axles or the like, such that it can rotate relative to the housingabout a generally horizontal axis (i.e., less than 45°, and more typically less than 10°, relative to a vertical gravitational axis when the machineis positioned for use). The drumhas an open endlocated along the rotation axis and facing the access opening, such that laundry items can be passed into the drumvia the access openingand open endof the drum.

The laundry machinehas a door, which is rotatably connected to the housingadjacent to the access opening. The dooris pivotably mounted to the housingby a hingeor the like, such that the dooris movable between a closed door position (shown in) in which the doorcloses the access opening, and an open door position (shown in) in which the doordoes not close the access opening. The door may include a structural framethat surrounds a transparent window, or other features as known in the art. The laundry machinemay include a washing machine (i.e., a machine that uses water or other liquids to cleanse the laundry), a drying machine, or a combination washer/dryer. In the shown example, the laundry machineis a dryer having a forced-air drying system(shown schematically) including one or more heaters or heat pumps configured to generate heated air, and one or more fans configured to circulate the heated air through the drum.

A door latch assemblyis provided to selectively hold the doorin the closed position. The door latch assemblygenerally includes a boltmounted to the door, a bolt handlemounted to the door, and a catchmounted to the housing. Referring now also to, the boltis movable, by operating the bolt handle, between a first bolt position such as shown in, and a second bolt position such as shown in. In the first bolt position, the boltis located on a first travel paththat is defined by movement of the doorbetween the closed door position (shown in solid lines) and an open door position (shown in broken lines). In the second bolt position, the boltis located on a second travel pathdefined by movement of the doorbetween the closed door position and the open door position. It will be understood that the first travel pathand the second travel pathare paths defined by the bolt, with the bolt in the respective bolt position, as the doormoves (i.e., the bolttraces the first travel pathwhen the dooris moved between the open and closed positions with the boltin the first bolt position, and the bolttraces the second travel pathwhen the dooris moved between the open and close positions with the boltin the second bolt position).

In the shown example, the first travel pathand second travel pathare spaced radially with respect to a rotation axisof the door, with the second travel pathbeing closest to the rotation axis. However, this arrangement is not strictly required. For example, the first travel pathmay be closer to the rotation axisthan the second travel path, or the first travel pathand second travel pathmay be equidistant in the radial direction to the rotation axis.

The bolt handleis mounted to the door, and at least a grip portion′ of the bolt handleextends from an exterior faceof the door when the dooris in the closed door position. Thus, a user can contact the grip portion′ to operate the bolt handle, even when the dooris closed. The bolt handleis operatively connected to the boltand configured to move the boltfrom the first bolt position to the second bolt position, such as shown in.

The catchis mounted to the housing, and positioned within the first travel path, but not within the second travel path. The catchis configured to engage the boltwhen the dooris in the closed door position and the boltis in the first bolt position, and the boltand the catchare configured to exert an opening force opposing movement of the boltalong the first travel pathupon movement of the doorfrom the closed door position towards the open door position. When the boltis in the first bolt position, the catchresists movement of the bolt, and thus the door, away from the closed door position. However, when the boltis in the second bolt position, the boltdoes not interact with the catch, and so the boltand doorcan be moved freely away from the closed position. This arrangement allows selective and independent control of the opening force required to overcome the catchand open the doorwhen the boltis in the first bolt position, and an unlatching force necessary to move the boltfrom the first bolt position to the second bolt position to thereby negate the need to apply the opening force to open the door.

Details of an exemplary door latch assemblyare shown in. In this case, the boltand bolt handleare made as a unitary part, such as by forming them both in a single injection molding process, but this is not strictly required. The handleincludes a grip portion′ that is accessible to the user when the dooris closed, and a slider portion″ that may be fully or partially concealed under a decorative trimor within the door frame. The slider portion″ is captured in place between a slider housingand the door frame, which together form a space in which the slider portion″ can move back and forth along a linear pathbetween the first bolt position as shown in, and the second bolt position as shown in. The slider housingmay include travel stops, such as a rear retaining wall, to prevent excessive movement of the slider portion″.

The linear pathmay be oriented in any direction. In the example of, the linear pathextends from the first bolt position towards the rotation axisof the door. In this case, the grip portion′ is pushed towards the door rotation axisto release the boltfrom the catch. In other cases, the linear pathmay be oriented to be parallel with the door rotation axis, or at other angles.

The catchis positioned to protrude into the slider housingat a location where it surrounds the boltwhen the bolt is in the first bolt position. However, sliding the boltto the second bolt position removes the boltfrom the confines of the catch.

The door latch assemblymay include features to control or influence the position or movement of the boltalong the linear path. For example, the bolt handlemay include one or more resilient members, such as springs or blocks of resilient material (e.g., elastomeric foam), that generate a force that must be overcome to move the bolt.

One example of a resilient member is shown inas a pair of cantilevered springs. Each springextends from the slider portion″ of the bolt handle, and includes a protrusionthat extends perpendicular to the linear path. The protrusionengages one or more detentsformed in the door(e.g., in the slider housing) when the bolt handleis at one or more respective locations along the linear path, and thus operatively connects the boltto the door. In this case, a respective first detentis positioned to receive each spring's protrusionwhen the boltis in the first bolt position, and a respective second detentis positioned to receive each spring's protrusionwhen the boltis in the second bolt position. Each cantilevered springgenerates a restoring force that drives the respective protrusioninto the respective detent,, and this restoring force must be overcome to release the protrusionsfrom the detents,

The arrangement ofprovides an unlatching force to hold the boltin the first bolt position. The unlatching force must be overcome to move the boltout of the first bolt position and into the second bolt position. The magnitude of the unlatching force may be regulated by selecting the shapes and sizes of the protrusionand detent, and by selecting the restoring force of the cantilevered spring (e.g., by selecting appropriate dimensions or material properties). The magnitude of the unlatching force is independent of the magnitude of the opening force required to pull the door open when the boltis in the first bolt position. Thus, the door latch assemblymay be configured to have a relatively high opening force, such as a magnitude between 9 pounds force and 15 pounds force, and a relatively low unlatching force, such as less than 5 pounds force.

The shape, position and construction of the springsmay be modified in various ways while still providing an unlatching force that is independent of the door opening force. For example, a single springmay be used or the locations of the springsmay be changed. As another example, each springmay be formed as a separate part, such as a ribbon of spring steel bent to form a protrusion, that is attached to the bolt handleor bolt. The positions of the protrusionsand detentsalso may be reversed (e.g., protrusionson the doorand detentson the bolt handle). The springsalso may be replaced by other resilient members, such as a compression spring located between the slider portion″ and the rear retaining wall. In such cases, the protrusionsand detentsmay be omitted. Other alternatives and variations will be apparent to persons of ordinary skill in the art in view of the present disclosure.

The boltand catchmay have any construction suitable to generate an opening force to resist accidental opening of the doorcaused by normal internal operating forces (e.g., laundry movement), while allowing the doorto open upon applying a sufficiently large force to overcome the opening force by pushing from inside the door, or pulling from the outside the door.

Details of an exemplary boltand catchare shown in. Here, the catchis formed by a pair of opposed leaf springs,that extend along the first travel pathand are curved towards each other to form the catch receptacle. The bolthas a rhombus shape, as viewed perpendicular to the first travel path, with a wedge-shaped entry facedirected towards the closed door position, and a wedge-shaped exit facedirected towards the open door position. The entry faceis configured to spread apart the leaf springs,upon moving the doorto the closed position while the boltis in the first bolt position. When the doorreaches the fully closed position while the boltis in the first bolt position, the leaf springs,move towards each other to at least partially surround the exit face. Moving the doorfrom the closed position towards the open position causes the exit faceof the boltto contact and spread apart the leaf springs,

In this embodiment, the shapes and material properties of the leaf springs,and entry faceaffect the magnitude of the force required to close the door with the boltin the first bolt position, and the shapes and material properties of the leaf springs,and exit faceaffect the magnitude of the opening force with the boltin the first bolt position. The closing force and opening force may be selected to be the same or different by choosing appropriate shapes for the leaf springs,and bolt. For example, in the shown embodiment, the wedge-shaped entry facetapers at a first angle Ato an entry wedge tip′, and the wedge-shaped exit facetapers at a second angle Ato an exit wedge tip′. The leaf springs,have similar tapered regions against which the entry faceand exit facepress to spread the leaf springs,apart. The first angle Aand the second angle A(and the corresponding faces of the leaf springs,) may be equal to each other, in which case the opening force will be approximately equal to the closing force. Alternatively, the angles A, A(or leaf springs faces) may have different angles to provide greater or lesser leverage to force the leaf springs,apart, leading to different opening and closing forces.

The boltand catchmay be configured to generate a preload force to hold the doorwhen the dooris in the closed position. For example, the exit facemay be dimensioned such it holds the leaf springs,spread slightly apart to generate a restoring force against the exit face, even when the dooris fully closed. Such preload force helps prevent the doorfrom being able to open slightly before requiring the opening force to be overcome to fully open the door. The preload force can also generate friction to resist movement of the boltto the second bolt position. The boltalso may include features to ensure that the preload force is generated when the dooris closed with the boltin the second bolt position, and then moved to the first bolt position to lock the door. For example, the boltmay have a tapered tip′ that is shaped to push apart the leaf springs,as the boltis moved from the second bolt position to the first bolt position while the dooris closed. This tapered tip′ also ensures that the side edges of the leaf springs,do not block the boltfrom being moved from the second bolt position to the first bolt position when the dooris closed.

Other embodiments may use other boltsand catches. For example, the boltmay have a round shape, rather than a rhombus shape. As another example, the catchmay be formed by rigid arms that are connected to the housingby resilient springs that bias the arms together. In other cases, the catchmay include a single cantilevered arm with a protrusion or hook that holds the bolt. The catchalso may include a rigid pin while the boltincludes a pair of resilient springs that snap over the pin when the dooris opened or closed with the boltin the first bolt position. In this case, the springs that form the boltmay be oriented such that the pin slides between them as the bolt is moved from the second bolt position to the first bolt position, in a manner essentially the same as how the boltofslides between the springs forming the catch. Other alternatives and variations of a boltand catchwill be apparent to persons of ordinary skill in the art in view of the present disclosure.

show another alternative embodiment of a door latch assembly. In this case, the bolt handleis pivotally connected to the doorby a bolt handle hinge, such that the bolt handlerotates relative to the doorabout a bolt handle rotation axis, which may or may not be parallel to the door rotation axis. The bolt handleis operatively connected to the boltby an intermediate linkage, such that rotation of the bolt handlecauses translational movement of the boltalong the linear path. In this case, the intermediate linkageincludes a single link that is pivotally connected at one end to the bolt handleand at the other end to the bolt. However, other intermediate linkages may have multiple links, cam-and-follower linkages, sliding links (pin in slot or lost motion), and so on. The intermediate linkage also may include a rack and pinion arrangement, such as by providing a pinion gear on the bolt handleand a toothed rack on the bolt. Other alternatives and variations will be apparent to persons of ordinary skill in the art in view of the present disclosure.

In the embodiment of, the boltis slidingly mounted to the door(e.g., by being captured in a slider housingor mounted on a track or tracks), and also operatively connected to the doorby a resilient member to generate an unlatching force that must be overcome to move the boltfrom the first bolt position to the second bolt position. The resilient member may include a cantilevered springthat engages detents, such as described above, or other suitable structures. In this case the resilient member is a tension springthat connects the doorto the bolt handle, and generates a restoring force to pull the bolt handleinto a position corresponding to the first bolt position. Thus, the tension springis operatively connected to the boltto generate an unlatching force that biases the boltto the first bolt position.

show another embodiment of a door latch assembly. Here, the boltis slidingly mounted to the door to move along a linear path, and the bolt handleis slidingly mounted to the door to move at an angle (e.g., perpendicular) to the linear path. In this case, the bolt handleis operatively connected to the boltby an intermediate linkage including a pinand slotarrangement. The pinis fixed to the bolt, and fits within a slotformed in the bolt handle. Movement of the bolt handlecauses the slotto act as a cam to drive the pinand thus move the bolt. A compression springis provided to generate an unlatching force to bias the bolttowards the first bolt position. If desired, a protrusion and detent arrangement may be provided to resiliently hold the boltat one or more particular locations.

show another embodiment of a door latch assembly. In this case, the bolt handleand boltare integrally formed as a single unit, and mounted to the doorby a bolt handle hinge. The bolt handle hingeallows the boltand bolt handleto rotate about a common rotation axis, which can be referred to as a bolt rotation axisor a bolt handle rotation axis. A resilient member, such as a tension spring, connects the boltand bolt handleto the doorto provide an unlatching force that must be overcome to move the boltfrom the first bolt position to the second bolt position.

show another embodiment of a door latch assembly, in which the boltand the bolt handleare separately pivotally connected to the door. The boltis mounted to the doorby a bolt hingeto rotate about a bolt rotation axis, and the bolt handleis mounted to the doorby a bolt handle hingeto rotate about a bolt handle rotation axis. The bolt rotation axisand bolt handle rotation axismay be parallel to each other and to the door rotation axis, but neither parallel arrangement is strictly required. In this case, the boltis operatively connected to the bolt handleby an intermediate linkage, such as the single link described previously, and operatively connected to the doorby a resilient member in the form of a compression springthat generates an unlatching force that must be overcome to move the boltfrom the first bolt position to the second bolt position.

show another exemplary embodiment, in which the boltis mounted to the machine housing, and the catchis mounted to the door. In this case, the first travel pathis located closer to the door rotation axisthan the second travel path. While the positions of the boltand catchare reversed with respect to their mounting locations, their structure and operation can otherwise be the same as described above in relation to the embodiment of. Similarly, any of the other embodiments described herein may be reversed similarly to the embodiment of.

It will be appreciated from the foregoing that the boltand bolt handlecan have any number or variety of operative connections to the doorand to each other. It will also be appreciated that the foregoing embodiments may be modified by replacing features in one embodiment with features in another embodiment. For example, a compression springas shown in the embodiment ofcould be used in an embodiment otherwise constructed according to. Still further, it will be understood that the boltand bolt handlemay be mounted to the doorto have any number of respective movement paths, including linear paths, rotational paths, and variations thereof (e.g., movement along a complex curve via sliders or a four-bar linkage or the like). Other alternatives and variations will be apparent to persons of ordinary skill in the art in view of the present disclosure.

Embodiments such as those described herein can be configured to provide washing or drying machine door latch assemblies that can simultaneously satisfy internal force opening requirements to provide reliable operation and safety, and external force opening requirements to provide accessibility to users who might have limited ability to apply force to open the door from the outside. This is achieved by isolating, completely or to a large degree, the external force opening requirements from the internal force opening requirements. Thus, the internal force to open the door may be established at a relatively high magnitude (e.g., 9 pounds force or greater), while the external force to open the door may be established at a relatively low magnitude (e.g., 5 pounds force or less). Such embodiments can provide the full range of functionality without require an expensive electrical control system or the like. Furthermore, at least some embodiments may be configured to retrofit to existing door assemblies, either as a service kit or as a factory-installed option.

While embodiments may beneficially provide an external opening force that is less than the internal opening force, this is not strictly required in all cases. Embodiments may provide other advantages beyond the reduced comparative opening force. For example, an embodiment may beneficially provide a bolt handle that moves in a rotating path while the bolt moves in a linear path, or vice versa. As another example, an intermediate linkage may be provided to redirect the operating direction of the bolt as compared to the bolt handle, to thereby provide greater flexibility to design the manner in which the user engages the door. These or other benefits may be realized in other embodiments, which may or may not also provide a reduced external opening force. The present disclosure describes a number of inventive features and/or combinations of features that may be used alone or in combination with each other or in combination with other technologies. The embodiments described herein are all exemplary, and are not intended to limit the scope of the claims. It will also be appreciated that the inventions described herein can be modified and adapted in various ways, and all such modifications and adaptations are intended to be included in the scope of this disclosure and the appended claims.