CUSHION CLIP

This application claims priority to Japanese patent application serial number 2008-8607, the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a cushion clip. More particularly, the present invention relates to a cushion clip that is attached an attachment hole formed in either of a stationary member and a movable member while the cushion clip is positioned therebetween, so as to absorb an impact that can be produced when the movable member moves toward the stationary member.

2. Description of Related Art

This type of cushion clip is already known. Generally, in such a cushion clip, a cushioning portion that is capable of absorbing an impact is integrated with an engagement portion that is capable of engaging an attachment hole formed in a stationary member or a movable member. Further, in the cushion clip thus constructed, the cushioning portion is formed of a soft resin material and has a hollow and substantially cylindrical shape. When the movable member moves toward the stationary member, the cushioning portion is elastically deformed and compressed between the stationary member and the movable member. As a result, the impact can be absorbed. Thus, the cushion clip is capable of providing an impact absorbing function.

The cushion clip may preferably be used to absorb an impact that can be generated when a door (cover) of a glove box of a vehicle is closed. The cushion clip used in the glove box may provide following functions in addition to the impact absorbing function.

(1) The cushion clip can prevent the door of the glove box from vibrating while the vehicle is moving.

(2) The cushion clip can prevent the door from directly contacting the glove box even when the door is strongly pushed by hand or elbow of a passenger or the like, so as to prevent noise generation and damage of the door and/or the glove box.

(3) The cushion clip can absorb a dimensional error of the door, so as to prevent rattling of the door resulting from its inaccurate positioning due to the dimensional error of the door.

(4) The cushion clip can have a good appearance in size and shape when the door is opened.

Therefore, the cushion clip used in the glove box is required to have the following characteristics in order to provide the functions described above.

(a) When the door is closed, the cushion clip can be appropriately compressed, so as to generate a reaction force that is capable of preventing the glove box from vibrating.

(b) The cushion clip can generate a large reaction force when a large load is applied thereto.

(c) In order to generate a desired (required) reaction force regardless of magnitude of the dimensional error of the door, the cushion clip can generate a substantially constant reaction force over a wide range of amount of compression.

(d) The cushion clip is small and not have an irregular shape.

If the cushion clip does not have the characteristics described above, various problems can be produced. For example, the door of the glove box cannot be sufficiently prevented from vibrating. This may lead to noise generation. Further, the door cannot be smoothly closed.

Thus, the cushion clip used in the glove box is required to have the following characteristics with regard to a relation between the reaction force and the amount of compression.

(i) In an initial compression period of the cushion clip, as the amount of compression is increased, the reaction force can be quickly increased such that the desired reaction force can be quickly obtained.

(ii) In a middle compression period of the cushion clip, which corresponds to a period after the reaction force reaches a lower limit of the desired reaction force, as the amount of compression is increased, the reaction force can be slowly or gently increased.

(iii) In a terminal compression period of the cushion clip, which corresponds to a period after the reaction force reaches an upper limit of the desired reaction force (after the amount of compression reaches a desired amount of compression), as the amount of compression is increased, the reaction force can be quickly increased.

Further, a relation between the reaction force and the amount of compression in an ideal cushion clip is shown in FIG. 7 as an ideal reaction force line. As will be apparent from FIG. 7, the ideal reaction force line may preferably include an initial compression range (a range A-B), a middle compression range (a range B-E) and a terminal compression range (a range E-).

A reaction force at a point B in the ideal reaction force line corresponds to the lower limit of the desired reaction force (which will be referred to as a minimum reaction force). When the cushion clip is compressed until the minimum reaction force can be generated, the cushion clip is capable of effectively preventing the door of the glove box from vibrating and generating noise while the vehicle is moving. Further, a reaction force at a point E in the ideal reaction force line corresponds to the upper limit of the desired reaction force (which will be referred to as a maximum reaction force). When the cushion clip is compressed until the maximum reaction force can be generated, a lock device of the door cannot be easily unlocked. Further, when the cushion clip is further compressed until a reaction force greater than the maximum reaction force is generated, the lock device of the door is subjected to an excessive load. This may lead to malfunction of the lock device.

Thus, the desired reaction force substantially corresponds to a reaction force between the minimum reaction force and the maximum reaction force. As will be appreciated from FIG. 7, the middle compression range (the range B-E) of the ideal reaction force line is very wide. That is, in the ideal cushion clip, a range R of the amount of compression in which the desired reaction force can be generated is very wide. This means that the ideal cushion clip can generate the desired reaction force over a wide range of the amount of compression. Further, the range R of the amount of compression may be referred to as an effective stroke of the ideal cushion clip.

A known cushion clip is taught, for example, by Japanese Laid-Open Patent Publication No. 2006-153083. The cushion clip includes a hollow cushioning portion. The cushioning portion has a protrusion that is formed in a bottom wall portion thereof.

Further, another known cushion clip is taught, for example, by Japanese Laid-Open Patent Publication No. 2007-225093. The cushion clip includes a cushioning portion having an accordion side wall. The cushioning portion has a protrusion that is formed in a bottom wall portion thereof.

A cushion clip is shown in FIG. 8, which cushion clip has the substantially same construction as the cushion clip taught by Japanese Laid-Open Patent Publication No. 2006-153083. The cushion clip 101 includes a cushioning portion 110 that is capable of absorbing an impact, and an engagement portion 120 that is capable of attaching the cushioning portion 110 to a stationary member. The cushioning portion 110 is made of a soft material having elasticity. Conversely, the engagement portion 120 is made of a hard material having a predetermined rigidity. Further, the cushioning portion 110 has a side wall portion 112 having a cone-shaped outer surface 170 and a vertically extending cylindrical inner surface 180. In addition, the cushioning portion 110 has a cavity portion 140 that is defined by the inner surface 180 of the side wail portion 112. The cushioning portion 110 has a substantially circular opening 160 that is defined by an upper end periphery 112a of the side wall portion 112. Further, the cushioning portion 110 has a bottom wall portion 113 that is integrated with the side wall portion 112. The bottom wall portion 113 has a projection 190 that is upwardly projected from the bottom wall portion 113 toward the circular opening 160.

In the cushion clip 101, the side wall portion 112 can be deformed due to compressive performance thereof, so as to generate a reaction force. Therefore, when a load applied to the cushion clip 101 is changed, the reaction force generated by the deformed side wall portion 112 can be changed in a quadratic curve. As a result, a range of amount of compression in which desired reaction force can be generated is very narrow. Therefore, the cushion clip 101 cannot generate the desired reaction force over a wide range of the amount of compression. That is, an effective stroke of the cushion clip 101 is very short.

It is, accordingly, one object of the present invention to provide improved cushion clips.

SUMMARY OF THE INVENTION

For example, in one aspect of the present invention, a cushion clip is constructed to be attached to an attachment hole formed in either of a stationary member and a movable member while the cushion clip is positioned therebetween, so as to absorb an impact that can be produced when the movable member moves toward the stationary member. The cushion clip may include a hollow cushioning portion that is capable of absorbing the impact and has a substantially circular central opening, and an engagement portion that is integrated with the cushioning portion and is capable of engaging the attachment hole. The cushioning portion has a bottom wall portion and a side wall portion. The side wall portion has cone-shaped outer and inner surfaces that are linearly tapered from a proximal end thereof toward a distal end thereof. The side wall portion has a top portion that is formed in the distal end thereof. The top portion has a radially inwardly projected inner periphery that defines the central opening therein.

According to the aspect of the invention, in an initial compression period of the cushioning portion, the side wall portion of the cushioning portion can be deformed in a compression direction. Therefore, in the initial compression period, a reaction force generated by the deformed side wall portion can be increased quickly. Conversely, in a middle compression period of the cushioning portion, the side wall portion of the cushioning portion can be deformed outwardly without being substantially deformed in the compression direction. Therefore, in the middle compression period, the reaction force generated by the deformed side wall portion can be gently changed. In addition, the side wall portion can be smoothly and constantly deformed until the top portion of the side wall portion contacts the bottom wall portion of the cushioning portion. Therefore, the cushioning portion can constantly generate a desired reaction force over a very wide range of amount of compression. That is, an effective stroke of the cushion clip is very long. Therefore, it is not necessary to enlarge the whole of the cushion clip in order to lengthen the effective stroke of the cushion clip. In addition, the cushion clip can be deformed without being substantially bent over.

Optionally, the side wall portion may have a thickness that is reduced from the proximal end thereof toward the distal end thereof.

Other objects, features and advantages of the present invention will be readily understood after reading the following detailed description together with the accompanying drawings and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external perspective view of a cushion clip according to a representative embodiment of the present invention;

FIG. 2 is a longitudinal sectional view of the cushion clip;

FIG. 3 is a longitudinal sectional view of the cushion clip, which view illustrates a condition in which the cushion clip is in an initial compression period;

FIG. 4 is a longitudinal sectional view of the cushion clip, which view illustrates a condition in which the cushion clip is in an initial stage of a middle compression period;

FIG. 5 is a longitudinal sectional view of the cushion clip, which view illustrates a condition in which the cushion clip is in a stable stage of the middle compression period;

FIG. 6 is a longitudinal sectional view of the cushion clip, which view illustrates a condition in which the cushion clip is in a final stage of the middle compression period;

FIG. 7 is a graph illustrating an ideal reaction force line of an ideal cushion clip; and

FIG. 8 is a partially sectional elevational view of a conventional cushion clip.

DETAILED DESCRIPTION OF THE INVENTION

A detailed representative embodiment of the present invention will be described with reference FIGS. 1 to 7.

As shown in, for example, FIG. 3, a representative cushion clip 10 may preferably be positioned between a box main body 50 (a stationary member) of a glove box of a vehicle and a cover or door 54 (a movable member) of the glove box while the cushion clip 10 is secured to the box main body 50, so as to absorb an impact that can be produced when the door 54 is closed. The cushion clip 10 is composed of a cushioning portion 20 that is capable of absorbing the impact, and an engagement portion 40 that is capable of engaging an attachment hole 52 formed in the box main body 50. The cushioning portion 20 and the engagement portion 40 may preferably be integrated with each other.

As shown in FIG. 2, the cushioning portion 20 of the cushion clip 10 is formed as an integrally formed hollow member that is composed of a bottom wall portion 24 and a side wall portion 22. The side wall portion 22 has a cone-shaped outer surface 26 that is linearly tapered upwardly (i.e., from a proximal end 22a of the side wall portion 22 toward a distal end 22b of the side wall portion 22), and a cone-shaped inner surface 28 that is linearly tapered upwardly (i.e., from the proximal end 22a of the side wall portion 22 toward the distal end 22b of the side wall portion 22). Further, the outer and inner surfaces 26 and 28 may preferably be tapered upwardly such that the side wall portion 22 has a thickness that is reduced from the proximal end 22a thereof toward the distal end 22b thereof. Further, the cushioning portion 20 has a cavity portion 32 that is defined by the inner surface 28 of the side wall portion 22. In addition, the cushioning portion 20 has a substantially circular central opening 25 formed in an upper or top portion 30 that is formed in the distal end 22b of the side wall portion 22. The opening 25 is defined by an inner periphery 30a of the top portion 30 and is continuous with the cavity portion 32.

Further, as will be apparent from FIG. 2, the inner periphery 30a of the top portion 30 is radially inwardly projected. That is, the top portion 30 is thicker than the side wall portion 22. Therefore, a lower end 30b of the top portion 30 has a thickness greater than the thickness of the distal end 22b of the side wall portion 22. As a result, the opening 25 that is defined by the inner periphery 30a of the top portion 30 has a diameter smaller than the inner diameter of the distal end 22b of the side wall portion 22.

As shown in FIGS. 1 and 2, the side wall portion 22 has one or more (two in this embodiment) vent holes 23 passing therethrough. The vent holes 23 are respectively formed so as to be positioned closer to the bottom wall portion 24. Further, the vent holes 23 are arranged and constructed so as to not affect deformation characteristics of the cushioning portion 20.

As shown in FIG. 2, the engagement portion 40 of the cushion clip 10 is composed of a disc-shaped base portion 42 that is embedded in the bottom wall portion 24 of the cushioning portion 20, and an engagement leg 44 that is projected downwards. The engagement leg 44 is shaped to be inserted into the attachment hole 52 formed in the box main body 50 (FIG. 3).

The cushioning portion 20 is formed of elastomer. Conversely, the engagement portion 40 is formed of polypropylene. That is, the cushioning portion 20 and the engagement portion 40 are integrally formed by two-color molding of elastomer and polypropylene.

Next, an operation of the cushion clip 10 thus constructed will now be described in detail.

First, as shown by broken lines in FIG. 3, the cushion clip 10 is attached to the box main body 50 by inserting the engagement let 44 into the attachment hole 52 of the box main body 50.

Thereafter, a load is applied to the door 54, so that the door 54 starts to move toward the box main body 50. When the door 54 contacts the cushioning portion 20 of the cushion clip 10, the door 54 starts to compress the cushioning portion 20. At this time, as shown by solid lines in FIG. 3, the side wall portion 22 can be deformed in a compression direction while the outer and inner surfaces 26 and 28 are arcuately curved outwardly. In this condition, a reaction force generated by the compressed cushioning portion 20 (the deformed side wall portion 22) can be quickly increased in proportion to an amount of compression of the compressed cushioning portion 20.

This condition is referred to as an initial compression period of the cushioning portion 20, which corresponds to the initial compression range (the range A-B) of the ideal reaction force line shown in FIG. 7.

As shown in FIG. 4, after the initial compression period of the cushioning portion 20 is completed, the side wall portion 22 of the cushioning portion 20 can be deformed to have a cylindrical shape. In this condition, the reaction force generated by the compressed cushioning portion 20 can be gently increased.

This condition is referred to as an initial stage of a middle compression period of the cushioning portion 20, which corresponds to an initial range (a range B-C) in the middle compression range (the range B-E) of the ideal reaction force line shown in FIG. 7.

As previously described, in the cushion clip 10, the outer and inner surfaces 26 and 28 are tapered upwardly such that the side wall portion 22 of the cushioning portion 20 can be reduced upwardly in thickness. Further, the lower end of the top portion 30 has a thickness greater than the thickness of the distal end 22b of the side wall portion 22. That is, the cushioning portion 20 is constructed such that the upper end of the side wall portion 22 can be deformed most easily. Therefore, in the initial stage of the middle compression period of the cushioning portion 20, the distal end 22b of the side wall portion 22, that is continuous with the lower end 30b of the top portion 30, is arcuately flexed in vertical cross section while the top portion 30 of the side wall portion 22 can be depressed inwardly downwardly. Conversely, a substantial portion of the side wall portion 22 can simply be deformed outwardly without being deformed in the compression direction. Thus, the substantial portion of the side wall portion 22 can be deformed cylindrically so as to extend in parallel with the compression direction.

As shown in FIG. 5, when the cushioning portion 20 is further compressed, the substantial portion of the side wall portion 22 of the cushioning portion 20 can be deformed outwardly while it is deformed in the compression direction. In this condition, the reaction force generated by the compressed cushioning portion 20 can be gently increased.

This condition is referred to as an intermediate stage of the middle compression period of the cushioning portion 20, which corresponds to an intermediate range (a range C-D) in the middle compression range (the range B-E) of the ideal reaction force line shown in FIG. 7.

In the intermediate stage of the middle compression period of the cushioning portion 20, the cylindrically shaped side wall portion 22 of the cushioning portion 20 can be flexed at a flexure portion while it is arcuately deformed outwardly. As will be recognized, because the side wall portion 22 has the thickness that is reduced from the proximal end 22a thereof toward the distal end 22b thereof, as the load applied to the door 54 is changed, the side wall portion 22 can be smoothly and constantly flexed due to flexural performance thereof while the flexure portion is gradually moved downwards. Therefore, even when the load applied to the door 54 is changed (increased), the reaction force generated by the deformed side wall portion 22 can be gently changed (increased) while the amount of compression of the cushioning portion 20 can be increased. Thus, in this stage, a desired reaction force can be generated. Further, because no obstacle (e.g., projection) is positioned in the cavity portion 32 of the cushioning portion 20, the side wall portion 22 can be smoothly and constantly flexed until the top portion 30 of the side wall portion 22 contacts the bottom wall portion 24 of the cushioning portion 20.

As shown in FIG. 6, when the cushioning portion 20 is further compressed, the cushioning portion 20 reaches a condition in which the top portion 30 of the side wall portion 22 contacts the bottom wall portion 24 of the cushioning portion 20. In this condition, the reaction force generated by the compressed cushioning portion 20 reaches an upper limit of the desired reaction force.

This condition is referred to as a final stage of the middle compression period of the cushioning portion 20, which corresponds to a final point (a point E) in the middle compression range (the range B-B) of the ideal reaction force line shown in FIG. 7.

When the cushioning portion 20 is further compressed after the cushioning portion 20 reaches the final stage of the middle compression period thereof (after the top portion 30 of the side wall portion 22 contacts the bottom wall portion 24 of the cushioning portion 20), the side wall portion 22 can be flexed due to compressive performance thereof and not flexural performance thereof. Therefore, when the load applied to the door 54 is changed, the reaction force generated by the deformed side wall portion 22 can be sharply changed.

This condition is referred to as a terminal compression period of the cushioning portion 20, which corresponds to the terminal compression range (the range E-) of the ideal reaction force line shown in FIG. 7.

According to the above embodiment, in the intermediate stage of the middle compression period of the cushioning portion 20, which corresponds to the intermediate range (the range C-D) in the middle compression range (the range B-E) of the ideal reaction force line, the side wall portion 22 can be smoothly and constantly flexed until the top portion 30 of the side wall portion 22 contacts the bottom wall portion 24 of the cushioning portion 20. Therefore, the intermediate stage of the middle compression period of the cushioning portion 20 is very wide. Thus, the cushioning portion 20 can generate the desired reaction force over a very wide range of amount of compression thereof. That is, an effective stroke of the cushion clip 10 is very long. In addition, in this stage, the cushion clip 10 can be deformed without being substantially bent over.

Further, the cushioning portion 20 is formed of elastomer. Therefore, the cushioning portion 20 may have excellent deformability and shock absorbability. Conversely, the engagement portion 40 is formed of polypropylene. Therefore, the engagement portion 40 may have high rigidity so as to be stably attached to the attachment hole 52. In addition, the cushioning portion 20 and the engagement portion 40 are integrally formed by two-color molding. Therefore, the cushioning portion 20 and the engagement portion 40 can be securely connected to each other.

Naturally, various changes and modifications may be made to the present invention without departing from the scope of the invention. For example, in the present embodiment, the side wall portion 22 of the cushioning portion 20 is shaped so as to have the thickness that is reduced from the proximal end 22a thereof toward the distal end 22b thereof. However, the side wall portion 22 of the cushioning portion 20 may have a uniform thickness over the entire length thereof provided that the outer and inner surfaces 26 and 28 of the side wall portion 22 are respectively tapered upwardly.

Further, the cushioning portion 20 can be formed of, for example, rubber, soft resin or other such materials. Conversely, the engagement portion 40 can be formed of hard resin, for example, polyacetal resin. In addition, the cushioning portion 20 and the engagement portion 40 can be integrally formed by multi-color molding or insert molding. Moreover, the cushioning portion 20 and the engagement portion 40 can be integrally formed by single-color molding of rubber or elastomer.

A representative example of the present invention has been described in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present invention and is not intended to limit the scope of the invention. Only the claims define the scope of the claimed invention. Therefore, combinations of features and steps disclosed in the foregoing detail description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe detailed representative examples of the invention. Moreover, the various features taught in this specification may be combined in ways that are not specifically enumerated in order to obtain additional useful embodiments of the present invention.

CUSHION CLIP

Information

Publication Number

Date Filed

Date Published

Inventors

Original Assignees

CPC

US Classifications

International Classifications

Abstract

Description

Claims

Priority Claims (1)