Patent Application
20230203743
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 comprising 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 comprise 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.
Embodiments of inventions will now be described, strictly by way of example, with reference to the accompanying drawings, in which:
The laundry machine 100 has a door 110, which is rotatably connected to the housing 102 adjacent to the access opening 104. The door 110 is pivotably mounted to the housing 102 by a hinge 140 or the like, such that the door 110 is movable between a closed door position (shown in
A door latch assembly 112 is provided to selectively hold the door 110 in the closed position. The door latch assembly 112 generally includes a bolt 114 mounted to the door 110, a bolt handle 120 mounted to the door, and a catch 124 mounted to the housing 102. Referring now also to
In the shown example, the first travel path 116 and second travel path 118 are spaced radially with respect to a rotation axis 132 of the door, with the second travel path 118 being closest to the rotation axis 132. However, this arrangement is not strictly required. For example, the first travel path 116 may be closer to the rotation axis 132 than the second travel path 118, or the first travel path 116 and second travel path 118 may be equidistant in the radial direction to the rotation axis 132.
The bolt handle 120 is mounted to the door 110, and at least a grip portion 120′ of the bolt handle 120 extends from an exterior face 122 of the door when the door 110 is in the closed door position. Thus, a user can contact the grip portion 102′ to operate the bolt handle 120, even when the door 110 is closed. The bolt handle 120 is operatively connected to the bolt 114 and configured to move the bolt 114 from the first bolt position to the second bolt position, such as shown in
The catch 124 is mounted to the housing 102, and positioned within the first travel path 116, but not within the second travel path 118. The catch 124 is configured to engage the bolt 114 when the door 110 is in the closed door position and the bolt 114 is in the first bolt position, and the bolt 114 and the catch 124 are configured to exert an opening force opposing movement of the bolt 114 along the first travel path 116 upon movement of the door 110 from the closed door position towards the open door position. When the bolt 114 is in the first bolt position, the catch 124 resists movement of the bolt 114, and thus the door 110, away from the closed door position. However, when the bolt 114 is in the second bolt position, the bolt 114 does not interact with the catch 124, and so the bolt 114 and door 110 can be moved freely away from the closed position. This arrangement allows selective and independent control of the opening force required to overcome the catch 124 and open the door 110 when the bolt 114 is in the first bolt position, and an unlatching force necessary to move the bolt 114 from the first bolt position to the second bolt position to thereby negate the need to apply the opening force to open the door 110.
Details of an exemplary door latch assembly 112 are shown in
The linear path 130 may be oriented in any direction. In the example of
The catch 124 is positioned to protrude into the slider housing 148 at a location where it surrounds the bolt 114 when the bolt is in the first bolt position. However, sliding the bolt 114 to the second bolt position removes the bolt 114 from the confines of the catch 124.
The door latch assembly 112 may include features to control or influence the position or movement of the bolt 114 along the linear path 130. For example, the bolt handle 120 may 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 114.
One example of a resilient member is shown in
The arrangement of
The shape, position and construction of the springs 138a may be modified in various ways while still providing an unlatching force that is independent of the door opening force. For example, a single spring 138a may be used or the locations of the springs 138a may be changed. As another example, each spring 138a may be formed as a separate part, such as a ribbon of spring steel bent to form a protrusion 152, that is attached to the bolt handle 120 or bolt 114. The positions of the protrusions 152 and detents 154 also may be reversed (e.g., protrusions 152 on the door 110 and detents 154 on the bolt handle 120). The springs 138a also may be replaced by other resilient members, such as a compression spring located between the slider portion 120″ and the rear retaining wall 150. In such cases, the protrusions 152 and detents 154 may be omitted. Other alternatives and variations will be apparent to persons of ordinary skill in the art in view of the present disclosure.
The bolt 114 and catch 124 may have any construction suitable to generate an opening force to resist accidental opening of the door 110 caused by normal internal operating forces (e.g., laundry movement), while allowing the door 110 to open upon applying a sufficiently large force to overcome the opening force by pushing from inside the door 110, or pulling from the outside the door 110.
Details of an exemplary bolt 114 and catch 124 are shown in
In this embodiment, the shapes and material properties of the leaf springs 124a, 124b and entry face 114b affect the magnitude of the force required to close the door with the bolt 114 in the first bolt position, and the shapes and material properties of the leaf springs 124a, 124b and exit face 114b affect the magnitude of the opening force with the bolt 114 in 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 124a, 124b and bolt 114. For example, in the shown embodiment, the wedge-shaped entry face 114a tapers at a first angle A1 to an entry wedge tip 114a′, and the wedge-shaped exit face 114b tapers at a second angle A1 to an exit wedge tip 114b′. The leaf springs 124a, 124b have similar tapered regions against which the entry face 114a and exit face 114b press to spread the leaf springs 124a, 124b apart. The first angle A1 and the second angle A2 (and the corresponding faces of the leaf springs 124a, 124b) may be equal to each other, in which case the opening force will be approximately equal to the closing force. Alternatively, the angles A1, A2 (or leaf springs faces) may have different angles to provide greater or lesser leverage to force the leaf springs 124a, 124b apart, leading to different opening and closing forces.
The bolt 114 and catch 124 may be configured to generate a preload force to hold the door 110 when the door 110 is in the closed position. For example, the exit face 114b may be dimensioned such it holds the leaf springs 124a, 124b spread slightly apart to generate a restoring force against the exit face 114b, even when the door 110 is fully closed. Such preload force helps prevent the door 110 from 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 bolt 114 to the second bolt position. The bolt 114 also may include features to ensure that the preload force is generated when the door 110 is closed with the bolt 114 in the second bolt position, and then moved to the first bolt position to lock the door 110. For example, the bolt 114 may have a tapered tip 114′ that is shaped to push apart the leaf springs 124a, 124b as the bolt 114 is moved from the second bolt position to the first bolt position while the door 110 is closed. This tapered tip 114′ also ensures that the side edges of the leaf springs 124a, 124b do not block the bolt 114 from being moved from the second bolt position to the first bolt position when the door 110 is closed.
Other embodiments may use other bolts 114 and catches 124. For example, the bolt 114 may have a round shape, rather than a rhombus shape. As another example, the catch 124 may be formed by rigid arms that are connected to the housing 102 by resilient springs that bias the arms together. In other cases, the catch 124 may comprise a single cantilevered arm with a protrusion or hook that holds the bolt 114. The catch 124 also may comprise a rigid pin while the bolt 114 comprises a pair of resilient springs that snap over the pin when the door 110 is opened or closed with the bolt 114 in the first bolt position. In this case, the springs that form the bolt 114 may be oriented such that the pin slides between them as the bolt is moved from the second bolt positon to the first bolt position, in a manner essentially the same as how the bolt 114 of
In the embodiment of
It will be appreciated from the foregoing that the bolt 114 and bolt handle 120 can have any number or variety of operative connections to the door 110 and 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 spring 138c as shown in the embodiment of
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.
