Slider for Concealed Slide Fastener

This application is based on and claims priority under 35 USC § 119 from Japanese Utility Model Application No. 2024-001537 filed on May 16, 2024, the contents of which are incorporated herein by reference.

The present invention relates to a slider used for a concealed slide fastener in which when left and right element rows are meshed with each other, the meshed element rows are concealed so as not to be seen from a tape outer surface side exposed to the outside of a fastener tape.

As a slider used for a concealed slide fastener in the related art, the slider disclosed in Patent Literature 1 or Patent Literature 2 is known.

As illustrated in, a slider bodyfor the concealed slide fastener described in Patent Literature 1 includes a lower blade, railserected along side edges of the lower blade, left and right flangesextending in a direction in which the left and right flangesapproach each other from upper ends of the rails, a guide column, an attachment columnprotruding upward from the guide column, a lock clawattached to the attachment column, a clamperattached to the lock claw, and a pullattached to the clamper.

Further, as illustrated in, the concealed slide fastener is used in a state in which the slider bodyfor the concealed slide fastener, a pair of right and left fastener tapessewn to a fabricto which the fastener is attached, and fastener elementssewn to the fastener tapesare included. Each of the fastener tapesincludes a pair of right and left tape main portions, an element attachment portion, and a tape folding portionfolded in a U-shape along a tape length direction.

Regarding the slider bodyfor the concealed slide fastener described in Patent Literature 2,is a perspective view of the slider body, and similarly to, includes the lower blade, the railserected along the side edges of the lower blade, the left and right flangesextending in the direction in which the left and right flangesapproach each other from the upper ends of the rails, the guide column, the attachment columnprotruding upward from the guide column, the lock clawattached to the attachment column, the clamperattached to the lock claw, and the pullattached to the clamper.

However, regarding the slider for the concealed slide fastener described in each of Patent Literatures 1 and 2, when the slider is pulled up in a state in which a large lateral pulling force is applied to the fastener tapes (see an operation state in), a contact stress between the flanges of the slider and tape folding portions (portions corresponding to the tape folding portionsin) of the fastener tapes becomes large, and an operation feeling that flange tips are caught to the fastener tapes may be generated. In particular, in a case in which a thin fabric, a fabric having rough yarn weaves, or a fabric of a knit tape is used as the fastener tapes in order to achieve weight reduction and improve air permeability of the slide fastener, a phenomenon may occur that the flange tips bite into the fastener tapes and then it is difficult to further pull up the slider.

It is considered that when the flangesfurther protrude forward than the railsas in the slider illustrated in, this phenomenon is likely to occur due to a size and a protruding shape of protruding portions. Further, repetition of an opening and closing operation in a state in which the contact stress between the flanges and the fastener tapes of such a slider is large may cause the fastener tapes to be easily damaged, for example.

Therefore, the present invention has been made in view of the above circumstances, and provides a slider for a concealed slide fastener that has a reduced contact stress between flanges and fastener tapes of the slider, is more easily pulled up than that in the related art, and prevents flange tips from being caught to or biting into the fastener tapes.

A slider for a concealed slide fastener according to the present invention is a slider for a concealed slide fastener that includes

Further, in the slider for a concealed slide fastener, in some cases, regarding dimensions Wand Wdefined below, the ratio of W/Wis in a range of 25% to 35%.

Further, in the slider for a concealed slide fastener, in some cases, a radius of curvature of the flange inner-front curved portion is in a range of 1.2 mm to 2.0 mm.

Further, in the slider for a concealed slide fastener, in some cases, the radius of curvature of the flange inner-front curved portion is larger than a radius of curvature of a flange outer-front curved portion.

Further, in the slider for a concealed slide fastener, in some cases, a shape of the lower blade on a frontward opening side is a substantially elliptical shape elongated in a sliding direction of the slider, a major axis of the substantially elliptical shape is oriented in a front-rear direction of the slider, and a minor axis thereof is oriented in the left-right direction of the slider.

Further, in the slider for a concealed slide fastener, in some cases, a length Din a front-rear direction of the lower blade existing forward with respect to the front end portion of each of the rails is larger than 30% of a length DO in the front-rear direction of the entire slider.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Further, the present invention is not limited to the embodiment described below.

Here, in the description of the present invention, a side from which fastener elements are separated is defined as a front side, a side from which the fastener elements are meshed is defined as a rear side, a sliding direction of a slider is defined as a front-rear direction (a length direction), a direction orthogonal to the front-rear direction and parallel to fastener tapes is defined as a left-right direction (a width direction), and a direction orthogonal to the front-rear direction and the left-right direction is defined as an up-down direction.

A slider for a concealed slide fastener according to the embodiment of the present invention will be described.

is a perspective view of a body of the slider according to the present embodiment,is a plan view of the slider body,is a side view of the slider body,is a view of the slider body as viewed from a rear direction, andis a view of the slider body as viewed from a front direction.is a view of a cross section taken along a line B-B inas viewed from an arrow direction.

As illustrated in these drawings, a slider bodyaccording to the present embodiment includes, as a basic structure, a lower blade, a pair of left and right rails (,) erected along side edges of the lower bladein the left-right direction, left and right flanges (,) extending in a direction in which the left and right flanges (,) approach each other from upper ends of the pair of left and right rails (,), a guide columnerected from the lower bladebetween the left and right flanges (,), and attachment columns (,) disposed above the guide column. The slider bodyhas a frontward openingand a rearward opening, and an element passageis formed between the frontward openingand the rearward opening.

The lower bladehas a thickness direction in the up-down direction, and has a symmetrical shape in the left and right direction. The shape of the lower bladeon the front side (the side of the frontward openingand the left and right sides of the guide column) is a substantially elliptical shape elongated in the sliding direction of the slider, a major axis of the substantially elliptical shape is oriented in the front-rear direction of the slider, and a minor axis thereof is oriented in the left-right direction of the slider. Accordingly, on the front side of the lower blade, a portion having a rounded shape of the lower bladeis largely exposed on the left and right sides of the guide column.

Each of the pair of rails (,) is formed of a curved plate-like member having a rail inner surfaceand a rail outer surface, and the railsare erected toward the front direction from a rear end portion of the lower bladealong the left and right side edges.

As illustrated in, the guide columnis erected from a central portion of the lower bladein the left-right direction near the frontward openingof the slider body. Further, as illustrated in, the front attachment columnand the rear attachment columnare provided on an upper surface of the guide column. The front attachment columnhas a substantially rectangular parallelepiped shape. Further, an upper surface portion of the front attachment columnis provided with a groovefor attaching a spring of a lock claw, which extends in a rectangular shape from a front end portion toward the rear side.

The rear attachment columnhas a substantially triangular shape with the front side as a bottom side and the rear side as an apex in a plan view. Further, the rear attachment columnhas a substantially triangular shape that is high on the front side and is low on the rear side in a side view. In the plan view, an insertion hole for a claw portion of the lock claw is provided in a central portion of the triangular shape. A pull attachment recessis formed between the front attachment columnand the rear attachment column. The lock claw integrated with a plate spring and a pull (or a pull clamper) are attached to the groovefor attaching the spring and the pull attachment recessand are fixed by caulking or the like, and then the obtained member is used as the slider for a concealed slide fastener (this point is the same as the technique disclosed in Patent Literature 2).

A substantially concave passage-like space formed by the lower blade, the pair of left and right rails (,), and the pair of flanges (,) serves as the element passagethrough which the fastener elements (not shown) pass.

The pair of flanges (,) are symmetrical in the left and right direction, and are plate-like members having a thickness direction in the up-down direction. The pair of flanges (,) extend inward to face each other from the pair of rails (,) erected along the left and right side edges of the lower blade.

As illustrated in, for convenience of description, an edge portion of the flangeis described by being divided into a flange rear portion, a flange inner surface-rear portion, a flange inner-central portion, a flange inner-front curved portion, and a flange outer-front curved portion. Specifically, first, an edge portion on a rearward openingside serves as the flange rear portion, the flange inner surface-rear portioncontinues forward from the flange rear portion, and the flange inner-central portionfurther continues from the flange inner surface-rear portion. The flange inner-central portionis a portion extending linearly. The flange inner-front curved portionextends continuously from the flange inner-central portion. The flange inner-front curved portionis a portion that extends curvedly toward the outside of the slider body. A boundary point between the flange inner-central portionand the flange inner-front curved portionis referred to as a start pointof the flange inner-front curved portion. The start pointof the flange inner-front curved portion is an end point of a linear portion of the flange inner-central portion, and is a start point of a curve of the flange inner-front curved portion. Further, the flange inner-front curved portionreaches a flange front end portion, and the flange outer-front curved portionextends further outward from the flange front end portion. When the shapes of the flange and the rail are compared and described as described above, the “curve” or the “linear” means a curve line or a straight line with respect to a boundary line formed when the slider bodyis viewed in a plan view as illustrated in.

The flange inner-central portionhas an inclined linear shape extending in the front-rear direction. The flange inner-front curved portionhas a substantially arc shape. In order to solve the above problems to be solved by the present invention, it is important to set a radius R of curvature of the flange inner-front curved portionas large as possible and set the entire flange inner-front curved portionto have a gradual curve shape. The flange outer-front curved portionhas a substantially arc shape. It is preferable that a radius R of curvature of the flange outer-front curved portionis also set as a radius of curvature as large as possible to form a gradual curve shape.

The flange front end portionserves as a portion of the flangethat is the foremost when the slider is viewed in the front-rear direction. The flangehas a width in the left-right direction and a thickness in the up-down direction, and in consideration of the width and the thickness, the foremost portion of the flangeis defined as the flange front end portion. That is, the flange front end portionmay be determined as one point, may be determined as a linear portion (a portion which is a straight line connecting the flange inner-front curved portionand the flange outer-front curved portionand is a straight line parallel to the left-right direction of the slider), and may be determined as a planar portion (a planar portion parallel to the left-right direction and the up-down direction of the slider). As illustrated in, surfaces of the flange rear portions, the flange inner surface-rear portions, the flange inner-central portions, the flange inner-front curved portions, and the flange outer-front curved portionsof the pair of flanges (,) are chamfered.

Subsequently, as illustrated in, the pair of rails (,) are erected along the left and right side edges of the lower blade. Surfaces of the pair of rails (,) on the inner side of the slider are the rail inner surfaces (,), which are inclined or curved surfaces appropriately designed to guide the elements. Here, for convenience of description, when the slider is viewed in the front-rear direction, a foremost portion of the railis defined as a rail front end portion. The railhas a thickness in the left-right direction and a thickness in the up-down direction, and in consideration of the thicknesses, the foremost portion of the railis defined as the rail front end portion. That is, the rail front end portionmay be determined as one point, may be determined as a linear portion (a linear portion parallel to the left-right direction of the slider), and may be determined as a planar portion (a planar portion parallel to the left-right direction and the up-down direction of the slider).

As can be easily understood from, the shape of the lower bladeon the front side (the side of the frontward opening) in the slider according to the present invention is a substantially elliptical shape elongated in the sliding direction of the slider, the major axis of the substantially elliptical shape is oriented in the front-rear direction of the slider, and the minor axis thereof is oriented in the left-right direction of the slider. In other words, the above can also be expressed as “a length Din the front-rear direction of the lower bladeexisting forward of the rail front end portionis larger than 30% of a length DO in the front-rear direction of the entire slider”. The shape of the lower bladeon the front side (the side of the frontward opening) in the slider defines a limit at which the railscan be extended when it is desired to extend the railslonger toward the front side, this point will be described later.

Next, a position relation among the rail front end portion, the flange front end portion, and the start pointof the flange inner-front curved portion in the slider will be described with reference to. The left side of each ofshows a plan view (a) of a slider body, and the right side of each ofshows a cross-sectional view (b) of the slider body. As in the case of, the cross-sectional view (b) is a view of the cross section taken along the line B-B inas viewed from the arrow direction.

Reference lines Yand Y′ illustrated inare flange rear end portion reference lines Yand Y′, and are straight lines in the left-right direction that pass through rearmost end portions of flange rear portionsand. Reference lines Yand Y′ are straight lines in the left-right direction that pass through flange front end portionsand. Reference lines Yand Y′ are straight lines in the left-right direction that pass through start pointsandof flange inner-front curved portions. Reference lines Yand Y′ are straight lines in the left-right direction that pass through rail front end portionsand.

(Note that as a method of expressingreference signs, a dash is added to the reference signs in the figure of a conventional example for the lines indicated by the same definitions, and 2 is added to the digit in the hundreds place of the reference signs in the figure of the conventional example for the portions having the same definitions.)

The lengths in the front-rear direction from the flange rear end portion reference lines Yand Y′ to the flange front end portionsand(distances between the reference lines Yand Y′ and the reference lines Yand Y′) are set to Land L′, the lengths in the front-rear direction from the flange rear end portion reference lines Yand Y′ to the start pointsandof the flange inner-front curved portions (distances between the reference lines Yand Y′ and the reference lines Yand Y′) are set to Land L′, and the lengths in the front-rear direction from the reference lines Yand Y′ to the rail front end portionsand(distances between the reference lines Yand Y′ and the reference lines Yand Y′) are set to Land L′.

First, in an example of the present invention, the position relation among the rail front end portion, the flange front end portion, and the start pointof the flange inner-front curved portion will be described with reference to. In the slider for a concealed slide fastener according to the embodiment of the present invention illustrated in, the respective values Lto Lare determined to satisfy the following Expression (1).

1>3>2  Expression (1)

That is, in the slider for a concealed slide fastener according to the embodiment of the present invention, the flange front end portionis located forward of the rail front end portion, and the start pointof the flange inner-front curved portion is located behind the rail front end portion.

The slider for a concealed slide fastener according to the embodiment of the present invention as described above is still the same as the conventional example in that a part of the flange inner-front curved portionof the flangeextends forward from the rail front end portion. In order to avoid a phenomenon that flange tips are caught to or bite into the fastener tapes, which is the problem to be solved by the present invention, in the first place, there may be an idea that the flange inner-front curved portionmay not extend forward from the rail front end portion. However, if the flangesare too short, when the fastener is closed, the fastener tapes become too easy to move in the up-down direction on the side of the frontward opening(a state in which the fastener tapes flap in a front-back direction), and it becomes difficult to properly guide the elements to element meshing positions at the guide column. Therefore, the flangeitself cannot be made shorter than in the related art (that is, the front side of the flangecannot be made shorter). As another idea, it is also conceivable to extend the railsforward as compared with those in the related art to eliminate extending portions on the front side of the flanges, but such a change cannot be made because there is a limitation due to the shape of the lower blade. That is, as illustrated in (b) of, in both the present example and the conventional example, the railshave already been extended forward to about the maximum extent, and when the railsare further extended forward, tips of the railsare extended to enter the inner side of the slider in the left-right direction, so that another significant problem occurs that the fastener elements are less likely to enter the inside of the slider on the side of the frontward openingwhen the fastener is closed.

Under the assumption that there is the above restriction, how to reduce the phenomenon that the flange tips are caught to the fastener tapes is an important technical point for solving the problem, and the technical significance of the solution achieved in the present invention will be described in detail below.

Here, in order to describe the technical significance of the present invention, the conventional example to be compared is described with reference to, and subsequently, a reason why the flange tips bite into the fastener tapes and a countermeasure thereof will be described with reference to.

A basic structure according to the conventional example described with reference tois substantially the same as that of the example except for an improvement point according to the present invention, but when the basic structure according to the conventional example is described anew so as not to cause misunderstanding, the conventional example includes a lower blade, a pair of left and right rails (,) erected along side edges of the lower blade in the left-right direction, left and right flanges (,) extended in a direction in which the left and right flanges (,) approach each other from upper ends of the pair of left and right rails (,), a guide column erected from the lower blade, and an attachment column disposed above the guide column.

Further, for the sake of convenience, as respective portions of the flange, a flange inner-front curved portion, a flange outer-front curved portion, a flange inner-central portion, a flange inner surface-rear portion, a flange rear portion, a flange front end portion, the start pointof the flange inner-front curved portion, and the rail front end portionare defined based on the same definitions as in the example, and are denoted by the reference signs as in.

The lower bladeand the lower blade of the conventional example have the same shape. Further, the guide columnand the guide column of the conventional example also have the same shape.

In addition, as a difference between the example and the conventional example, the conventional example is different from the example in that the start pointof the flange inner-front curved portion is located forward of the rail front end portion. That is, in the conventional example, there is a relation that the length L′ in the front-rear direction from the reference line Y′ to the start pointof the flange inner-front curved portion is longer than the length L′ in the front-rear direction from the reference line Y′ to the rail front end portion. That is, an expression L′>L′>>L′ is satisfied.

Next, in order to clarify the technical significance of the present invention, a relation between forces acting on the elements, the slider, and the fastener tape in the example and the conventional example will be described with reference to.

Each ofis a diagram for illustrating a relation between positions of the elements and the force acting on the slider in a state in which the slider is pulled up in order to close the slide fastener.is a diagram of the example according to the present invention, andis a diagram of the conventional example. In, reference signs Eand Eand reference signs E′ and E′ denote the elements, and state diagrams of the reference sign Eand the reference sign E′ are schematic diagrams illustrating a state in which the elements are in contact with a guide surface (the rail inner surface) of the rail(a state in which the elements are in contact with the railat the foremost position at which the elements are guided). Further, state diagrams of the reference signs Eand E′ are schematic diagrams illustrating a state in which the elements are not in contact with the guide surface (the rail inner surface) of the rail(a state immediately before the elements come into contact with the rail inner surfaceof the rail). Since it is difficult to see in (b) of, the element in the state of the reference sign E′ is not intentionally illustrated. Further, in, the force acting on the slide fastener (for example, a lateral pulling force generated in the fastener when the slider is operated in a closing direction) is indicated by an arrow F. When the element is located at the position of the reference sign E, a stress that the railreceives from the element Eis indicated by an arrow F. Similarly, when the element is located at the position of the reference sign E, the flangeis in contact with a folding portion of the fastener tape (the tape folding portioninthat is described for Patent Literature 1), and thus the flangereceives a stress due to this contact, and this force is indicated by an arrow F. When the element is in contact with the guide surface (the rail inner surface) of the railas at the position of the reference sign E, the force acting on the slide fastener can also be received by the railas F, and thus the force Facting on the flangeis reduced accordingly. Since the force Facting on the flangeis also a force acting on the folding portion of the fastener tape, a decrease in Fmeans a decrease in a load applied to the fastener tape. On the other hand, when the element is located at the position of the reference sign E, the force acting on the slide fastener cannot be received by the railas Fbecause the element is not in contact with the guide surface (the rail inner surface) of the rail, and thus the force acting on the slide fastener is received as the force Facting on the flange, and therefore, the force acting on the folding portion of the fastener tape is also considered to be increased accordingly. However, in the example, since the start pointof the flange inner-front curved portion is located rearward of the rail front end portion, when the element is located at the position of the reference sign E, a portion of the fastener tape in contact with the flangechanges to a smooth curve, that is, the “flange inner-front curved portion”, the fastener tape has already been guided to the “flange inner-front curved portion”, and an advancing direction thereof is greatly changed such that the orientation of the fastener tape extends from the front-rear direction toward the left-right direction. Therefore, since a component force acting between the flangeand the folding portion of the fastener tape is reduced, the load acting on the folding portion of the fastener tape is also reduced.

Next, a discussion relating to the above force acting on the fastener tape will be described in the case of the conventional example. In, since the element is in contact with a guide surface (a rail inner surface) of the railwhen the element is in the state of the reference sign E′, the force acting on the slide fastener can also be received as F′ by the railas in the above example, so that a stress F′ acting on the flangeis reduced accordingly. However, in a configuration of L′>L′ as in the conventional example, there is a zone ΔY in which the element is not guided by the raileven before the flangechanges to the “flange inner-front curved portion”. As illustrated in, the zone ΔY is between the rail front end portionand the start pointof the flange inner-front curved portion (between the straight line Y′ in the left-right direction that passes through the rail front end portionand the straight line Y′ in the left-right direction that passes through the start pointof the flange inner-front curved portion). The element denoted by the reference sign E′ indicates a state of an element in the zone ΔY. Since the element E′ is not guided by the rail, the lateral pulling force received by the slide fastener cannot be received by the railat the position of this element, and most of the lateral pulling force must be received by the flange. In addition, in the zone ΔY, the flangeis not the flange inner-front curved portionbut the flange inner-central portion. Since the flange inner-central portionis a linear edge portion extending in the front-rear direction rather than the left-right direction of the slider, the component force acting between the flangeand the folding portion of the fastener tape is not largely reduced, and the load is largely applied to the folding portion of the fastener tape. The force is indicated by an arrow Fmax in. This Fmax is considered to be comparable to the sum of F′ and F′. As described above, in the conventional example, there is a region in which the load acting on the folding portion of the fastener tape becomes extremely large.

As described in the above analysis, the zone ΔY in the conventional example is a flange range (ΔY) in which the folding portion of the fastener tape needs to receive a high load, and thus the zone ΔY is hereinafter referred to as a “high load flange range ΔY”. As described above, in the conventional example, since almost all of the lateral pulling force of the tape is received on the flange side in the high load flange range ΔY, it is considered that a contact stress between the flanges and the fastener tapes increases, and the phenomenon that the flanges are caught to the fastener tapes occurs.

On the other hand, according to, since an expression L>Lis satisfied in the example, the flange range (ΔY) is not generated. Further, in the example, since a flange curve is gentle at the position of the element E(in a state of being inclined to extend not in the front-rear direction but in the left-right direction), a component force (the component force acting between the flangeand the folding portion of the fastener tape) received from the external force Fis small.