WO2024003580A1

WO2024003580A1 - Refuse container

Info

Publication number: WO2024003580A1
Application number: PCT/GB2023/051735
Authority: WO
Inventors: Carl Taylor
Original assignee: Shift Logic Ltd
Current assignee: Shift Logic Ltd
Priority date: 2022-06-30
Filing date: 2023-06-30
Publication date: 2024-01-04
Anticipated expiration: 2024-12-30
Also published as: GB202209653D0; GB2620181A

Abstract

In one aspect, a refuse container (1) comprises a first section (2) and second section (4) hingedly connected to each other to move between an open and closed position, and a retaining mechanism (13) to releasably maintain the container 1 in the closed position, and further comprising two tabs (9, 17) that are offset relative to each other yet within 100mm, to allow the tabs (9, 17) to be separated single-handedly by a 'finger-snapping' motion. In another aspect, a refuse container (1) comprises a collar to be formed from two portions (20, 21) with at least one protruding member (27) to retain a liner to the collar. The aspects individually and combined facilitate the relining of a refuse container with a bin liner.

Description

Refuse Container

This invention relates to a refuse container such as a waste bin, for example for use in a domestic environment such as a domestic kitchen.

Background

A number of designs of refuse container are known for use in domestic kitchens. Typically, such refuse containers are designed to include a container to hold a liner or bag, the refuse container having a closable lid. Typically, the opening of the liner or bag is folded over the upper rim or collar of the container, the lid is placed over the upper rim or collar and the liner is held in place by friction between the liner, the outer surface of the upper rim or collar of the container and the inner surface of the lid. In use, the user opens the lid to allow objects to be deposited within the liner, after which the lid is closed. In some cases the lid is manually opened and closed. Some designs include a foot pedal mechanism whereby the lid can be opened without the user need to touch the lid.

After a period of time, the liner becomes full and the user needs to remove and replace the liner. To do this, in a typical design, the lid is removed and the liner is pulled from the upper opening of the container.

However, the weight of the objects within the liner, and the tendency of the liner to stick to or seal against the inner surface of the container can result in the user needing to apply a significant pulling load to the liner to extract the liner from the container. Some users find the application of such a load awkward, and so struggle to remove a filled liner from the container.

Furthermore, the liners are typically of a relatively thin, light weight plastics material and the application of a large load thereto to remove the liner from the container can result in the liner tearing or splitting, and this may result in spillage of materials from within the liner which is undesirable.

One solution that overcomes some of these issues is a front-opening refuse container, which comprises two sections attached together by a hinge that can transition between an open configuration and a closed configuration. This allows for the liner to be removed when the container is in an open configuration, decreasing the degree to which the liner sticks to the inner surface of the container and thereby reducing the puling load applied by the user to the liner. In order to keep the container in the closed configuration when the liner is in use, the refuse container is provided with a retaining mechanism, typically in the form of a latch or a pair of magnets. However, the use of both hands or a degree of force is frequently required to release the retaining mechanism, which increases the difficulty of replacing the liner, especially for users with mobility issues. Moreover, as more objects are added to the liner, the portion of the liner that is in contact with the outer surface of the upper rim or collar of the container and the inner surface of the lid will be subjected to increasing stress due to the weight of the objects within the liner. This force can result in a strain in the liner, causing deformation and breakage of the liner, or the liner coming loose from the upper rim or collar of the container, preventing the liner from being held in an open position to receive further objects. This means that the liner either has to be removed from the refuse container without being filled, thereby increasing waste, or reinstalled over the upper rim or collar of the container, inconveniencing the user. In order to prevent the liner coming loose from the collar of the container, the liner is sometimes arranged such that a greater portion of the liner is folded over the collar of the container. However, this liner configuration can result in an excess portion of liner protruding from below the lid of the refuse container, which is both unhygienic and unsightly.

It is an object of the invention to provide a refuse container in which at least some of the disadvantages associated with known arrangements are overcome or are of reduced effect.

Statement of Invention

According to a first aspect of the invention, there is provided a refuse container comprising: a first section; a second section, the second section being hingedly connected to the first section about a hinge axis along an axial direction to allow the first and second sections to transition between an open configuration and a closed configuration; a lid mountable upon the first and second sections when the first and second sections are in the closed configuration, the lid being openable to allow access to the interior of the container; and a retaining mechanism, wherein the retaining mechanism is configured to releasably maintain the container in the closed position, wherein the first section comprises a first tab arranged on a portion of the first section that is in contact with the second section when the first and second sections are in the closed configuration, and wherein the second section comprises a second tab arranged on a portion of the second section that is in contact with the first portion when the first and second sections are in the closed configuration, wherein the first tab and second tab are misaligned with respect to each other along the axial direction of the refuse container and wherein the first tab and second tab are arranged such that, when the first and second sections are in the closed configuration, the first tab and second tab are within 100 mm of each other along the axial direction of the refuse container.

By providing the first and second tabs that can be operated in opposite directions, the refuse container can be opened with one hand, thereby facilitating opening of the refuse container with the minimal amount of effort.

Each of the first tab and second tab may be integrally formed with the first and second sections respectively. This facilitates the manufacture of the refuse container by reducing the amount of assembly.

It will be appreciated that the tabs are structures providing a handle surface and that are misaligned so as to be offset in a partially overlapping or spaced apart manner exposing free surfaces thereof against which two fingers (or thumb and finger) of a user’s hand can press, simultaneously in opposite directions, sufficiently close to allow a user to single-handedly apply opposite forces to prise the two sections apart to open the container. This reduces and practically avoids a risk of inadvertent pulling or moving the entire container as may be observed with single handles. The tabs may be provided as a multi-tab configuration, and/or as a reversible insert, to be adjustable for left-handed and right-handed use.

The first tab and second tab may be arranged such that, when the first and second sections are in the closed configuration, the first and second tab are adjacent to each other in the axial direction. Alternatively, the first tab and second tab may be arranged such that, when the first and second sections are in the closed configuration, the first tab and second tab partially overlap each other along a portion of the length of each of the first tab and second tab in the axial direction.

These arrangements of the first and second tabs ensure that the tabs may be operated easily with one hand.

The first tab and second tab may be of a similar size. For example, the first tab and second tab may have a similar length in the axial direction and/or a radial direction perpendicular to the axial direction and/or the first tab and second tab may have a similar area in cross-section. The first tab and second tab may be substantially the same size.

By ensuring the first tab and second tab have similar sizes or the same size, the first tab and second tab may be operated using a similar amount of force to open the refuse container, facilitating the opening of the refuse container by one hand.

The retaining mechanism may comprise at least one pair of magnets or magnetically attracting components, optionally the pair of magnets comprises a first magnet that is attached to the first section and a second magnet that is attached to the second section, such that when the first and second sections are in the closed configuration, the first and second magnets or components are in contact with each other and the retaining mechanism maintains the first and second sections in the closed configuration by the magnetic attraction between the first and second magnets or magnetically attracting components, respectivley.

By using at least one pair of magnets as the retaining mechanism, the first and second sections may be kept in the closed configuration easily and with a minimum number of moving parts that may wear and need replacing.

The first section and second section may be provided with a first collar portion and a second collar portion respectively, wherein, when the first and second sections are in the closed configuration, the first collar portion and second collar portion are arranged to form a collar configured to receive a liner having an opening, wherein the first collar portion and second collar portion are each provided with at least one protruding member, the at least one protruding member protruding from a surface of each respective collar portion, wherein optionally the at least one protruding member is configured to, in use, retain the liner in an open arrangement.

By providing the at least one protruding member on each of the first and second collar portions, there is an additional means by which the liner is held in an open arrangement over the collar of the refuse container. This provides the result that the liner may be held in the open arrangement regardless of the weight of objects deposited within the liner, without an excess portion of liner protruding from below the lid of the refuse container. This improves the efficiency and hygiene of the refuse container, as well as reducing waste from partially filled or damaged liners being removed prematurely.

The respective at least one protruding member may be formed integrally with each respective collar portion. This facilitates the manufacture and assembly of the refuse container.

The respective at least one protruding member may be provided on an exterior surface of the respective collar portion.

The refuse container may further comprise a base member upon which the refuse container stands, in use. The base member may be attached to the first section.

The base member provides additional rigidity and stability for the refuse container.

The base member may comprise at least one recessed portions on the interior surface of the base member.

The provision of at least one or more recessed portions means that any liquid that may come out of the liner, for example through a hole in the liner, is collected within the refuse container and does not leak out. Additionally or alternatively to the at least one recessed portion, the base member may further comprise a lip portion on the interior surface of the base member, wherein the lip portion is arranged such that the lip portion is in contact with at least part of an interior surface of the second section when the first and second sections are in the closed configuration. The lip portion may be attached to or formed integrally with the base member.

The provision of the lip portion means that any liquid that may come out of the liner, for example through a hole in the liner, is collected within the refuse container and does not leak out. Furthermore, the lip portion may act as a backstop to prevent the second section from rotating about the hinge axis past the position in which the first and second sections are in the closed configuration.

According to a second aspect of the invention, there is provided a refuse container comprising: a first section; a second section, the second section being hingedly connected to the first section about a hinge axis along an axial direction to allow the first and second sections to transition between an open configuration and a closed configuration; and a lid mountable upon the first and second sections when the first and second sections are in the closed configuration, the lid being openable to allow access to the interior of the container, wherein the first section and second section are provided with a first collar portion and a second collar portion respectively, wherein, when the first and second sections are in the closed configuration, the first collar portion and second collar portion are arranged to form a collar configured to receive a liner having an opening, wherein the first collar portion and second collar portion are each provided with at least one protruding member, the at least one protruding member protruding from a surface of each respective collar portion, wherein the at least one protruding member is configured to, in use, retain the liner in an open arrangement.

Any one or more embodiments of the first aspect may be combined with any one or more embodiments of the second aspect.

For the avoidance of doubt, whenever reference is made herein to ‘comprising’ or ‘including’ and like terms, the invention is also understood to include more limiting terms such as ‘consisting of’ and ‘consisting essentially’. Furthermore, whenever reference is made herein to “interior” or “exterior”, these terms are understood to refer to the interior or exterior of the refuse container when in the closed configuration. Whilst the invention has been described above, it extends to any inventive combination of the features set out above, or in the following description, drawings or claims. For example, any features disclosed in relation to the first aspect of the invention may be combined with any features of the second aspect of the invention and vice versa.

Description of Figures

The invention will further be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is an exploded view of a refuse container in accordance with an embodiment of the invention;

Figure 2 is a schematic view of the refuse container of Figure 1 in a closed configuration in accordance with the invention;

Figure 3 is a schematic view of the refuse container of Figure 1 and Figure 2 in an open configuration in accordance with the invention;

Figure 4a is a schematic sectional view, to an enlarged scale, illustrating part of the refuse container of Figures 1 to 3; and

Figure 4b is a schematic sectional view, to an enlarged scale, illustrating part of the refuse container of Figures 1 to 3 with a liner.

Detailed Description

Figure 2 shows a schematic representation of a refuse container 1 according to an embodiment of the present invention. Figure 1 shows the refuse container 1 in an exploded view and Figure 3 shows the refuse container 1 of Figure 2 in an open configuration. The illustrated embodiment of the present invention will be described with reference to each of these Figures interchangeably.

Refuse container 1 comprises a first section 2 and a second section 4 that are joined together by a hinge 10. Hinge 10 is in the form of a piano hinge, and is formed of hinge components 11 , 12 and hinge rod 24. In the illustrated embodiment, hinge components 11 , 12 are formed as separate components that are attached to the first section 2 and second section 4 respectively. In an alternative embodiment, hinge component 11 may be formed integrally with first section 2 and, additionally or alternatively, hinge section 12 may be formed integrally with second section 4. Other hinge types may be used.

The first and second sections 2, 4 may be formed of a metal or metal alloy, such as stainless steel, or may be formed from a polymer or polymer blend, such as polypropylene. Each of the first and second sections 2, 4 may be painted or otherwise coated in a coating layer that may be formed from the same material as the first and second sections 2, 4, or from a different material.

The first section 2 and second section 4 are hingedly connected to each other by hinge 10 such that first section 2 and second section 4 can rotate about hinge axis H between a closed configuration, as illustrated in Figure 2, and an open configuration, as shown in Figure 3. When the first section 2 and second section 4 are in the closed configuration, they are configured to form a container 5 having a diameter D1. In the illustrated embodiment, the first section 2 and second section 4 are arranged such that, in the closed configuration, they form a cylindrical container 5 having a circular cross-section. However, other container and cross- sectional shapes are possible, such as generally square, rectangular, or other polygonally shaped footprints.

First section 2 and second section 4 are provided with trim components 6, which forms the point of attachment for trim portions 8, 16, which are attached to the trim components 6 attached to first section 2 and second section 4 respectively.

First section 2 is provided with a first collar portion 20 and second section 4 is provided with a second collar portion 21 . When the first and second sections 2, 4 are in the closed configuration, the first collar portion 20 and the second collar portion 21 are arranged to form a collar 22. The dimensions of the first collar portion 20 and second collar portion 21 are configured such that, when the first and second sections 2, 4 are in the closed configuration, the diameter D2 of the collar 22 is less than the diameter D1 of the container 5.

In the illustrated embodiment, the first and second sections 2, 4 are attached to trim components 6, trim portions 8, 16 and first and second collar portions 20, 21 by tapping screws 7. However, each of these components may be attached together by alternative methods, such as adhesive or rivets. In the illustrated embodiment, trim portions 8, 16 are formed integrally with tabs 9, 17. Alternatively, tabs 9, 17 may be formed separately, or may be formed integrally with first and second sections 2, 4.

Refuse container 1 further comprises lid 28. Lid 28 may be formed in any number of forms, as is widely known in the art. However, in the illustrated embodiment, lid 28 comprises a body 29 of cylindrical shape, corresponding to the cylindrical shape of the first and second sections 2, 4 in the closed configuration, and a cover 30 pivotally mounted to the body 29. The cover 30 is sprung or otherwise biased towards an open position relative to the body 29, and a releasable latch mechanism is provided to allow the cover 30 to be latched in a closed position. The exterior diameter of the lid DI is equal to the diameter of the container D2. Each of the first collar portion 20 and second collar portion 21 further comprise a lip portion 23, which act as a base on which the lid 28 rests when the first and section sections 2, 4 are in the closed configuration, and a wall portion 25.

In use, a liner 40, for example in the form of a thin plastics material bag or sack, is located within the container 5. The liner 40 is arranged such that an upper, open end thereof of folded over the wall portions 25 of the first and second sections 2, 4, and the body 29 of the lid 28 covers the exposed part of the liner 40, securing the liner 40 in position between the wall portions 25 and body 29 of the lid 28 such that the liner 40 is retained in an open arrangement. The user may place objects within the refuse container 1 by operating the latch mechanism to allow the cover 30 to open, and subsequently closing the cover 30 and latching it in position. When the liner 40 becomes full and requires removal and replacement, the lid 28 is removed and the upper end of the liner 40 is released from the collar 22. Subsequently, the second section 4 is moved relative to the first section 2 to open the container 5. With the container 5 opened in this manner, the liner 40 is readily accessible within the container 5 and may easily be removed therefrom. The load that must be applied to the liner 40 to remove it from the container 5 is greatly reduced compared to traditional refuse container designs, and so the risk of tearing, ripping or splitting of the liner 40 is greatly reduced. Once the liner 40 has been removed, the container 5 may be returned to its closed configuration and a new liner 40 located therein, the upper edge of the new liner 40 being folded around the wall portions 25 of the collar 22 and the lid 28 positioned to close the container 5 and secure the new liner 40 in position in an open arrangement. The presence of the lid 28 further serves to retain the cylinder 5 in its closed condition.

Each of the first collar portion 20 and second collar portion 21 are provided with at least one protruding member 27 protruding from a surface of the respective first and second collar portions 20, 21 . In the illustrated embodiment, the at least one protruding member 27 is on an exterior surface of the first and second collar portions 20, 21 . Alternatively, the at least one protruding member 27 may be provided on an interior surface of the first and second collar portions 20, 21 . The at least one protruding member 27 may be formed integrally with the first and second collar portions 20, 21 , or may be attached to the first and second collar portions 20, 21 by methods known in the art.

The at least one protruding member 27 is configured to have a radial dimension such that, when the refuse container 1 is in use, the at least one protruding member 27 engages the liner 40 against the inner surface of the body 29 of the lid 28. This provides an additional frictional force acting on the liner 40 to hold the liner 40 in the open configuration regardless of the weight of objects deposited within the liner 40, without an excess portion of liner 40 protruding from below the lid 28. The refuse container 1 further comprises a retaining mechanism 13 configured to releasably maintain the refuse container 1 in the closed position. In the illustrated embodiment, the retaining mechanism 13 is provided by two pairs of magnets 26 arranged in the trim portions 8, 16 of the first and second sections 2, 4. When the first and second sections 2, 4 are in the closed configuration, the magnets 26 are arranged such that two separate pairs of magnets are in contact with one another and maintain the refuse container 1 in the closed configuration by attraction between each magnet 26 in the magnet pairs. However, the retaining mechanism may instead be a different number of magnets 26 arranged in alternative positions within the refuse container 1 , or an alternative retaining mechanism, such as a latch mechanism. Suitable magnets for use in the retaining mechanism of the present invention include Feyg LW001 neodymium bar magnets.

When the refuse container 1 is in the closed configuration, first tab 9 and second tab 17 are located in proximity to, but displaced from, one another in an axial direction parallel to hinge axis H. The first tab 9 and second tab 17 are within 100 mm of each other along the axial direction of the refuse container 1 parallel to hinge axis H. Preferably, the first tab 9 and second tab 17 are within 50 mm of each other along the axial direction of the refuse container 1.

By providing the first and second tabs 9, 17 in an offset manner, they can be operated by applying force to their exposed surfaces in opposite directions, the refuse container 1 can be opened with single-handedly, for instance using two fingers to perform a ‘snapping’ gesture, thereby facilitating opening of the refuse container 1 with the minimal amount of effort.

As shown in Figure 2, the first tab 9 and second tab 17 are arranged such that, when the first and second sections 2, 4 are in the closed configuration, the first and second tab 9, 17 are adjacent to each other in the axial direction.

Alternatively, the first tab 9 and second tab 17 may be arranged such that, when the first and second sections 2, 4 are in the closed configuration, the first tab and second tab 9, 17 overlap each other along a portion of the length of each of the first tab 9 and second tab 17 in the axial direction.

The first tab 9 and second tab 17 may be of a similar size. For example, the first tab 9 and second tab 17 may have a similar length in the axial direction and/or a radial direction perpendicular to the axial direction. The first tab 9 and second tab 17 may have a similar area in cross-section. The first tab 9 and the second tab 17 may be substantially the same size. In the illustrated embodiment, as shown in Figure 2, the first tab 9 and the second tab 17 have the same size. Alternatively, the first tab 9 and second tab 17 may not be the same size. For example, the first tab 9 may be at least two-thirds of the size of the second tab 17 or vice versa. The refuse container further comprises a base member 14, upon which the refuse container 1 stands, in use. In the illustrated embodiment, the base member 14 is attached to first section 2 by brackets 29 and screws 32. However, the base member 14 may be formed integrally with the first section 2, or attached to the first section 2 by any method of attaching two components known in the art.

The base member 14 may comprise at least one recessed portion 15 on the interior surface of the base member 14 and/or a lip portion 18, which allows for the collection of liquid in the event of the liner 40 breaking, and preventing the refuse container 1 from leaking liquid. It will be appreciated that the description hereinbefore is of one example embodiment of the invention and that a wide range of modifications and alterations may be made thereto without departing from the scope of the invention as defined by the appended claims.

Claims

1 . A refuse container comprising: a first section; a second section, the second section being hingedly connected to the first section about a hinge axis along an axial direction to allow the first and second sections to transition between an open configuration and a closed configuration; a lid mountable upon the first and second sections when the first and second sections are in the closed configuration, the lid being openable to allow access to the interior of the container; and a retaining mechanism, wherein the retaining mechanism is configured to releasably maintain the container in the closed position, wherein the first section comprises a first tab arranged on a portion of the first section that is in contact with the second section when the first and second sections are in the closed configuration, and wherein the second section comprises a second tab arranged on a portion of the second section that is in contact with the first portion when the first and second sections are in the closed configuration, wherein the first tab and second tab are displaced from one another along the axial direction of the refuse container and wherein the first tab and second tab are arranged such that, when the first and second sections are in the closed configuration, the first tab and second tab are within 100 mm of each other along the axial direction of the refuse container.

2. A refuse container according to claim 1 , wherein the first tab and second tab are arranged such that, when the first and second sections are in the closed configuration, the first and second tab are adjacent to each other in the axial direction, and optionally partially overlap each other.

3. A refuse container according to claim 1 or 2, wherein the retaining mechanism may comprise at least one pair of magnets or magnetically attracting components.

4. A refuse container according to claim 3, wherein the pair of magnets comprises a first magnet that is attached to the first section and a second magnet that is attached to the second section, such that when the first and second sections are in the closed configuration, the first and second magnets are in contact with each other and the retaining mechanism maintains the first and second sections in the closed configuration by the magnetic attraction between the first and second magnets.

5. A refuse container according to any one of the preceding claims, wherein the first section and second section are provided with a first collar portion and a second collar portion respectively, wherein, when the first and second sections are in the closed configuration, the first collar portion and second collar portion are arranged to form a collar configured to receive a liner having an opening, wherein the first collar portion and second collar portion are each provided with at least one protruding member, the at least one protruding member protruding from a surface of each respective collar portion, and wherein optionally the at least one protruding member is configured to, in use, retain the liner in an open arrangement.

6. A refuse container according to claim 5, wherein the at least one protruding member of the first collar portion and/or the at least one protruding member of the second collar portion are formed integrally with the first and second collar portions respectively.

7. A refuse container according to claim 5 or 6, wherein the at least one protruding member is formed on an exterior surface of the first collar portion and/or the at least one protruding member is formed on an exterior surface of the second collar portion

8. A refuse container according to any one of the preceding claims, wherein the refuse container further comprises a base member upon which the refuse container stands, in use.

9. A refuse container according to claim 8, wherein the base member is attached to the first section.

10. A refuse container according to claim 8 or 9, wherein the base member may comprise at least one recessed portions on the interior surface of the base member.

11. A refuse container comprising: a first section; a second section, the second section being hingedly connected to the first section about a hinge axis along an axial direction to allow the first and second sections to transition between an open configuration and a closed configuration; and a lid mountable upon the first and second sections when the first and second sections are in the closed configuration, the lid being openable to allow access to the interior of the container, wherein the first section and second section are provided with a first collar portion and a second collar portion respectively, wherein, when the first and second sections are in the closed configuration, the first collar portion and second collar portion are arranged to form a collar configured to receive a liner having an opening, wherein the first collar portion and second collar portion are each provided with at least one protruding member, the at least one protruding member protruding from a surface of each respective collar portion, wherein the at least one protruding member is configured to, in use, retain the liner in an open arrangement.

12. A refuse container according to claim 11 , wherein the at least one protruding member of the first collar portion and/or the at least one protruding member of the second collar portion are formed integrally with the first and second collar portions respectively.

13. A refuse container according to claim 11 or claim 12, wherein the at least one protruding member is formed on an exterior surface of the first collar portion and/or the at least one protruding member is formed on an exterior surface of the second collar portion

14. A refuse container according to any one of claims 11 to 13, wherein the refuse container further comprises a retaining mechanism, wherein the retaining mechanism is configured to releasably maintain the container in the closed position, wherein the first section comprises a first tab arranged on a portion of the first section that is in contact with the second section when the first and second sections are in the closed configuration, and wherein the second section comprises a second tab arranged on a portion of the second section that is in contact with the first portion when the first and second sections are in the closed configuration, wherein the first tab and second tab are misaligned with respect to each other along the axial direction of the refuse container and wherein the first tab and second tab are arranged such that, when the first and second sections are in the closed configuration, the first tab and second tab are within 100 mm of each other along the axial direction of the refuse container.

15. A refuse container according to claim 14, wherein the first tab and second tab are arranged such that, when the first and second sections are in the closed configuration, the first and second tab are adjacent to each other in the axial direction.

16. A refuse container according to claim 14 or claim 15, wherein the retaining mechanism may comprise at least one pair of magnets.

17. A refuse container according to claim 16, wherein the pair of magnets comprises a first magnet that is attached to the first section and a second magnet that is attached to the second section, such that when the first and second sections are in the closed configuration, the first and second magnets are in contact with each other and the retaining mechanism maintains the first and second sections in the closed configuration by the magnetic attraction between the first and second magnets.

18. A refuse container according to any one of claims 11 to 17, wherein the refuse container further comprises a base member upon which the refuse container stands, in use.

19. A refuse container according to claim 18, wherein the base member is attached to the first section.

20. A refuse container according to claim 18 or claim 19, wherein the base member may comprise at least one recessed portions on the interior surface of the base member.