JP2003169762A - Toilet lid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toilet lid preventing its base end circumferential edge part from being deformed and deteriorating the external appearance and the function after the completion. <P>SOLUTION: The toilet lid 1 is attached to a stool-type toilet or its attachment device via a journal part 2 to be freely raised and fallen, formed by injection-molding melt resin in a metal mold, and has an approximately semi- elliptical plane surface. The thickness 4t of the tip circumferential edge part 4 positioned in the furthermost part perpendicular to the axial direction of the journal part 2 of the toilet lid 1 is set to approximately 120% of the thickness 5t of the toilet lid top surface part 5. A reinforcing rib 6a as reinforcing means for preventing the bent deformation is provided in the base end circumferential edge part 6 approximately in parallel to the axial direction 3 of the journal part 2 and the toilet lid top surface part 5 and the reinforcing rib 6a are connected to each other through a smooth continuous curved part 6b. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toilet lid which is attached to a toilet bowl so as to be upright and inclinable so as to cover an upper opening of a sitting toilet bowl.

[0002]

2. Description of the Related Art In a toilet bowl installed in a Western-style toilet, a toilet bowl or its accessory is used to cover the upper opening.
A toilet lid made of synthetic resin that is upside down like a toilet seat is attached. As a conventional toilet lid, for example, one as shown in FIG. 5 is generally used. A toilet seat 90 shown in FIG. 5 has a substantially semi-elliptical shape in a plan view, and is attached to a sitting toilet (not shown) or its accessory via a shaft support 91 so as to be capable of undulating.

Such a toilet lid 90 is generally formed by injection molding a synthetic resin. In the injection molding die, the base end peripheral edge portion 90 which is substantially parallel to the axial direction 91a of the shaft support portion 91 is formed.
A gate (not shown) for supplying the molten resin into the mold is provided near the center of b, and the direction of injection of the molten resin is normally the center of the base peripheral edge portion 90b as shown by the arrow 92. Is set to be substantially parallel to the top surface 90c of the toilet lid 90.

[0004]

The conventional toilet lid 90 depends on the type of resin, molding conditions, ambient temperature, etc., but an external force is applied immediately after completion to about 168 hours. Although not present, as shown in FIG. 5, the base end peripheral edge portion 90b may be deformed so as to bend.

When such deformation occurs in the toilet lid 90, the appearance of the toilet lid 90 deteriorates and its value as a product decreases, and the opening / closing operation of the toilet lid 90, the toilet seat, etc. is impaired, and the toilet lid 9
0 may not be completely closed.

[0006] Therefore, an object of the present invention is to provide a toilet lid that is not deformed flexibly at the peripheral edge of the base end after completion, which would deteriorate the appearance and function.

[0007]

When the flexural deformation of the base end peripheral edge portion 90b of the toilet lid 90 is examined from various angles, there are some unclear points, but the following matters are not the cause. It is supposed to be. Hereinafter, with reference to FIG.
The cause of flexural deformation and its solution will be described.

Since the vicinity of the tip peripheral edge portion 90a of the toilet lid 90 is far from the molten resin supply gate (not shown) provided in the injection molding die, the injection pressure tends to be small. The contraction amount of the tip peripheral edge portion 90a is larger than that of other portions. Also, when the thickness of the molded product is thicker, the shrinking force in the direction (plane direction) perpendicular to the thickness direction tends to increase when the resin shrinks. A relatively large tensile stress 96 is generated in the surface direction of the tip peripheral edge portion 90a having a large size. Therefore, as a result of the distal end peripheral portion 90a contracting in the peripheral surface direction so as to pull the other portion with a strong force, the vicinity of the shaft support portion 91 of the toilet lid 90 is deformed so as to open in the outer direction 93, respectively.
It is considered that this causes the proximal peripheral edge portion 90b to deform so as to bend.

On the other hand, the toilet lid 9 formed by injection molding
At 0, as a phenomenon peculiar to the injection molding resin, as shown in FIG. 6, the shrinkage rate in the direction MD parallel to the injection direction 92 of the molten resin in the injection molding step is the shrinkage rate in the direction TD perpendicular to the injection direction 92. Tends to be smaller. Therefore, a tensile stress 94 in the MD direction and a tensile stress 95 in the TD direction are generated on the top surface 90c of the toilet lid 90. Of these, the tensile stress 95 in the TD direction causes the bending of the base end peripheral portion 90b. It is thought to act to prevent it.

As described above, in the toilet lid 90 formed by injection molding, tensile stress 94 is applied to the tip peripheral edge portion 90a.
It is assumed that tensile stress 95, 96 is generated on the top surface 90c, and when these tensile stresses 94, 95, 96 act on each other and are balanced, the bending amount of the base end peripheral edge portion 90b is determined. To be done.

The present invention has been made based on the above findings, and the toilet lid of the present invention is attached to a stool-type toilet bowl or its accessory device so as to be capable of undulating via a shaft support portion and injection molding of molten resin. Is a toilet lid having a substantially semi-elliptical shape in a plan view, and the thickness of the tip peripheral portion located at the farthest portion in the direction perpendicular to the axial direction of the shaft support is the thickness of the toilet lid top surface portion. 10% to 90% of the above, and a reinforcing means for preventing flexural deformation is provided at the base end peripheral edge portion that is substantially parallel to the axial direction of the shaft support portion.

With this structure, the contraction force in the peripheral surface direction generated at the peripheral part of the tip due to the contraction of the resin after injection molding is reduced, and the contraction force and the contraction force generated at the top surface of the toilet lid are reduced. Since the bending deformation which is about to occur in the base end peripheral edge portion due to the combined action of the above is reliably prevented by the reinforcing means, after the completion, the bending deformation of the base end peripheral edge portion which deteriorates the appearance and the function is prevented. Become. The reinforcing means for preventing the bending deformation includes a reinforcing rib formed in the bending direction of the peripheral edge of the base end, a curved surface portion or a C surface portion formed between the toilet lid top surface and the reinforcing rib, and the peripheral edge of the base end. In addition to the reinforcing means for increasing the rigidity of the portion, especially the second moment of area, it is possible to adopt means for increasing the rigidity in the whole wavy shape except for the peripheral edge portion of the base end.

In addition, (direction T perpendicular to the molten resin injection direction
Resin after injection molding by forming a toilet lid with a synthetic resin having a shrinkage ratio after molding of D)-(shrinkage ratio after molding in a direction MD parallel to the molten resin injection direction) = 0.1 to 1.0. Since the contracting force in the TD direction generated on the top surface of the toilet lid due to the contraction is larger than the contracting force in the MD direction, the effect of preventing the flexural deformation of the base peripheral edge portion is increased, and the flexural deformation is more effectively performed. Can be prevented.

Further, a direction T perpendicular to the molten resin injection direction
By forming a synthetic resin with a shrinkage rate of 0.5 to 2.5 after molding on the toilet lid, the shrinkage force in the TD direction generated on the top surface of the toilet lid after injection molding is further increased than the shrinkage force in the MD direction. Since it can be increased, the action of preventing the bending deformation of the base end peripheral edge portion is increased, and the bending deformation prevention effect is further improved.

By using a synthetic resin containing any of crystalline resins such as polypropylene, polyethylene, polyacetal, polybutylene terephthalate, polyamide, and polyphenylene sulfide as the molten resin, these synthetic resins can be used after injection molding. Since the contraction rate in the direction is higher than the contraction rate in the MD direction, the contraction force in the TD direction generated on the top surface of the toilet lid after the injection molding becomes larger than the contraction force in the MD direction, and the bending deformation of the base end peripheral portion is suppressed. The action can be enhanced.

Further, by forming a toilet lid with a synthetic resin containing a needle-shaped crystal nucleating agent in the molten resin, the shape of the crystal nucleating agent causes a direction MD parallel to the injection direction of the molten resin after injection molding.
Since the shrinkage rate becomes larger in the direction TD perpendicular to the molten resin injection direction, the effect of preventing the bending deformation of the peripheral portion of the base end increases, and the bending deformation can be more effectively prevented. .

[0017]

1 is a perspective view showing a toilet lid according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line AA in FIG.

The toilet lid 1 according to the present embodiment is attached to a stool toilet or its accessories (neither is shown) via a shaft support 2 so as to be able to stand up and down, and a molten resin is put into a mold. The plane shape formed by injection molding has a substantially semi-elliptical shape. Then, the thickness 4t of the tip peripheral edge portion 4 located at the farthest portion in the direction orthogonal to the axial direction of the shaft support portion 2 of the toilet lid 1.
Is about 80% of the thickness 5t of the toilet lid top surface portion 5, and a reinforcing rib 6a is provided on the base end peripheral edge portion 6 that is substantially parallel to the axial direction 3 of the shaft support portion 2 as a reinforcing means for preventing bending deformation and the toilet lid. The top surface portion 5 and the reinforcing rib 6a are connected by a smooth continuous curved surface portion 6b. When the thickness 4t of the tip peripheral edge portion 4 of the toilet lid 1 is set to about 80% of the thickness 5t of the toilet lid top surface portion 5, optimum moldability can be obtained for resin molding.

By making the thickness 4t of the tip peripheral edge portion 4 relatively thin as described above, the contraction force in the peripheral edge surface direction generated in the tip peripheral edge portion 4 due to the resin contraction after injection molding is reduced and the reinforcement is achieved. By providing the rib 6a and the continuous curved surface portion 6b, the rigidity (second moment of area) of the base end peripheral edge portion 6 increases, so that the total action of the contracting force of the distal end peripheral portion 4 and the contracting force generated in the toilet lid top surface portion 5 is exerted. The bending deformation that is likely to occur in the base end peripheral edge portion 6 is reliably prevented by the reinforcing rib 6a and the continuous curved surface portion 6b, and after the completion of the toilet lid 1, the base end peripheral edge portion that deteriorates the appearance and function of the toilet lid 1 is completed. The bending deformation of the portion 6 does not occur.

The toilet lid 1 has a shrinkage rate after molding in a direction TD perpendicular to the injection direction 7 of molten resin-a shrinkage rate after molding in a direction MD parallel to the injection direction 7 of molten resin = 0.1 1.0
Since it is made of polypropylene resin, the contraction force in the TD direction generated on the toilet lid top surface 5 due to the resin contraction after injection molding becomes larger than the contraction force in the MD direction. The action to prevent flexural deformation also becomes relatively large,
Flexural deformation can be effectively prevented.

Further, since the toilet lid 1 is made of polypropylene resin having a post-molding shrinkage rate of 0.5 to 2.5 in the direction TD perpendicular to the molten resin injection direction 7, after the injection molding,
The contracting force in the TD direction generated on the toilet lid top surface portion 5 is larger than the contracting force in the MD direction, and this also effectively prevents the bending deformation of the base end peripheral edge portion 6.

In this embodiment, a synthetic resin containing polypropylene resin is used as the molten resin when the toilet lid 1 is injection-molded. However, since it does not deteriorate to this, polyethylene, polyacetal, polybutylene terephthalate is used. It is also possible to use a synthetic resin containing any of resins having crystallinity such as polyamide, polyphenylene sulfide and the like.

In the toilet lid 1, a needle-shaped crystal nucleating agent is mixed in the molten resin. For this reason, after injection molding, the shrinkage rate in the direction TD perpendicular to the molten resin injection direction is larger than that in the direction MD parallel to the molten resin injection direction. As a result, flexural deformation can be prevented more effectively.

Next, with reference to FIGS. 3 and 4, another embodiment of the toilet lids 21 and 31 will be described. Figure 3
4 is a partial cross-sectional view showing the vicinity of the base end peripheral edge portion 26 of the toilet lid 21, and FIG. 4 is a partial cross-sectional view showing the vicinity of the base end peripheral edge portion 36 of the toilet lid 31. In FIGS. 3 and 4, parts having the same functions and effects as the constituent parts of the toilet lid 1 shown in FIGS. 1 and 2 are denoted by the same symbols as those in FIGS. 1 and 2 and description thereof is omitted. To do.

In the toilet lid 21 shown in FIG. 3, a reinforcing rib 26a is provided in the bending direction of the base peripheral edge portion 26 as a reinforcing means for preventing the base end peripheral edge portion 26 from being bent and deformed. A C surface portion 26b is provided between the reinforcing rib 26a and the reinforcing rib 26a. By this, the rigidity (second moment of area) of the base end peripheral edge portion 26 increases, so that the base end peripheral edge portion 2
The flexural deformation of 6 can be prevented. Regarding the structure and functions of other parts, the toilet lid 1 shown in FIGS.
Is the same as.

In the toilet lid 31 shown in FIG. 4, the reinforcing rib 3 having a shape that hangs relatively long in the bending direction of the base end peripheral edge portion 36 serves as a reinforcing means for preventing the base end peripheral edge portion 36 from bending deformation.
6a is provided. By this, the above-mentioned toilet lid 1,
As in the case of 21, the rigidity (second moment of area) of the base end peripheral edge portion 36 increases, so that the base end peripheral edge portion 36 can be prevented from being flexibly deformed. The structure and functions of the other parts are the same as those of the toilet lid 1 shown in FIGS.

[0027]

The present invention has the following effects.

(1) In a toilet lid, which is attached to a stool-type toilet or its accessory device so as to be capable of ups and downs via a shaft supporting portion and is injection-molded with a molten resin, and has a substantially semi-elliptical planar shape, The thickness of the tip peripheral portion located at the farthest portion in the direction perpendicular to the axial direction is 10% to 8 of the thickness of the toilet lid top surface portion.
0%, and by providing reinforcing means for preventing flexural deformation on the base end peripheral edge part that is substantially parallel to the axial direction of the shaft support part, the flexure of the base end peripheral edge part that deteriorates the appearance and function after completion is completed. No deformation will occur.

(2) (direction T perpendicular to the molten resin injection direction)
Shrinkage rate after molding of D)-(Shrinkage rate after molding in a direction MD parallel to the molten resin injection direction) = 0.1 to 1.0 The action of preventing the flexural deformation is increased, and the flexural deformation can be more effectively prevented.

(3) Direction TD perpendicular to the molten resin injection direction
The synthetic resin having a post-molding shrinkage rate of 0.5 to 2.5 is formed on the toilet lid, so that the action of preventing the bending deformation of the peripheral edge portion of the base end is increased, and the bending deformation preventing action is further improved. .

(4) By using a synthetic resin containing any of crystalline resins such as polypropylene, polyethylene, polyacetal, polybutylene terephthalate, polyamide, and polyphenylene sulfide as the molten resin, bending deformation of the base end peripheral portion The effect of suppressing

(5) By forming a toilet lid with a synthetic resin containing a needle-shaped crystal nucleating agent in the molten resin, the effect of preventing the flexural deformation of the peripheral portion of the base end is increased, and the flexural deformation preventing effect is obtained. Is improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a toilet lid according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG.

FIG. 3 is a partial cross-sectional view showing a toilet lid according to another embodiment.

FIG. 4 is a partial cross-sectional view showing a toilet lid according to another embodiment.

FIG. 5 is a perspective view showing a conventional toilet lid.

FIG. 6 is a perspective explanatory view showing a stress distribution after injection molding of a conventional toilet lid.

[Explanation of symbols]

1,21,31 toilet lid 2 shaft support 3 axis direction 4 Advanced performance section 4t, 5t thickness 5,25 Toilet lid top 6,26,36 Base peripheral edge 6a, 26a, 36a Reinforcing ribs 6b Continuous curved surface 7 Molten resin injection direction 26b C surface part MD Direction parallel to molten resin injection direction TD Direction perpendicular to molten resin injection direction

Claims (5)

[Claims] 1. A toilet lid having a substantially semi-elliptical plan shape formed by injection-molding a molten resin, which is attached to a stool-type toilet bowl or an accessory device thereof so as to be capable of undulating, and is a shaft support portion. The thickness of the distal end peripheral portion located at the farthest portion in the direction perpendicular to the axial direction of the base is 10% to 90% of the thickness of the top surface of the toilet lid, and the base peripheral edge is substantially parallel to the axial direction of the shaft support. A toilet lid characterized in that a reinforcing means for preventing flexural deformation is provided on the portion. 2. (Shrinkage ratio after molding in a direction TD perpendicular to the molten resin injection direction) − (direction MD parallel to the molten resin injection direction)
2. The toilet lid according to claim 1, which is made of a synthetic resin having a post-molding shrinkage ratio of 0.1 to 1.0. 3. The toilet lid according to claim 1, which is made of a synthetic resin having a post-molding shrinkage ratio of 0.5 to 2.5 in a direction TD perpendicular to the molten resin injection direction. 4. The stool according to claim 1, wherein the molten resin is a synthetic resin containing any one of crystalline resins such as polypropylene, polyethylene, polyacetal, polybutylene terephthalate, polyamide and polyphenylene sulfide. lid. 5. The toilet lid according to claim 1, wherein the molten resin is a synthetic resin containing a needle-shaped crystal nucleating agent.