JP7801742B2 - Drain plug device - Google Patents

Description

The present invention relates to a drain plug device for opening and closing the drain outlet of a tank body.

Conventionally, drain plug devices have been known that can switch the open/close state of a drain outlet formed in a tank body (e.g., a bathtub or washbasin) by remotely operating a plug cover.

Drain plug devices generally include a plug lid with a cylindrical insertion portion and a support shaft to which the plug lid is attached by inserting the tip (upper end) of the support shaft into the insertion portion. As the support shaft reciprocates (moves up and down), the plug lid (more specifically, the packing portion attached to the plug lid) switches between contact and non-contact with a specified contact object (for example, a cylindrical drain outlet member inserted into the drain or the tank body itself), thereby switching the open/closed state of the drain (see, for example, Patent Document 1, etc.).

In addition, to prevent the plug cap from easily coming off the support shaft, a locking portion provided on the tip of the support shaft may be configured to lock onto a locking portion formed on the inner circumference of the insertion portion. Furthermore, drain plug devices having a locking portion and a locking portion may be provided with a retraction force applying portion (e.g., a spring) that applies a retraction force in the downward direction to the support shaft. In this type of drain plug device, when the drain outlet is closed, the plug cap (packing portion) contacts the contact object, causing the support shaft to move back (down) to a position before the maximum retraction (downward) position. This maintains a state in which the retraction force is transmitted from the retraction force applying portion to the plug cap via the locking portion and the locking portion. This allows the packing portion to press against the contact object, improving watertightness when the drain outlet is closed.

JP 2015-214813 A

In a drain plug device having an engaged portion and an engaging portion as described above, when the plug cap is removed from the support shaft during installation, maintenance, or cleaning of the device, the tip of the support shaft must be inserted into the insertion portion, and the engaging portion must be engaged with the engaged portion when the support shaft returns to its original position (i.e., a state in which the plug cap is properly attached to the support shaft, hereinafter referred to as the "engaged state"). In this regard, it is desirable to make it easier to achieve the engaged state, both in terms of the ease of installation and ease of use of the device.

The present invention was made in consideration of the above circumstances, and its purpose is to provide a drain plug device that makes it easier to achieve the fitting state, thereby improving workability and ease of use.

Below, each means suitable for achieving the above objective will be explained item by item. Where necessary, the specific effects of the corresponding means will also be noted.

Means 1. A rod-shaped support shaft that can move back and forth and has a locking portion on the tip side,
a retraction force applying portion that applies a retraction force in a backward movement direction to the support shaft;
a plug cover that can open and close a drain outlet formed in the tank body in accordance with the reciprocating movement of the support shaft;
The stopper cap is
A plate-shaped lid portion;
An annular packing portion attached to the lid portion and contacting a predetermined contact target portion when the drain outlet is in a closed state;
a cylindrical insertion portion provided on the back side of the lid portion and through which the tip end side of the support shaft is inserted;
a locked portion provided in the insertion portion and configured to be able to lock the locking portion of the support shaft inserted into the insertion portion,
When the tip side of the support shaft is inserted into the insertion portion and the locking portion is locked with the locked portion when the support shaft returns, the state is called an engaged state.
When the drain outlet is closed in the fitted state, the support shaft is positioned in a position before the maximum return position due to the contact of the packing portion with the contact object portion, thereby maintaining a state in which a retraction force is transmitted from the retraction force application portion to the lid portion via the engaged portion and the engaging portion, and the packing portion is pressed against the contact object portion.
At least one of the locking portion and the locked portion is provided with an inclined surface that gradually moves away from the central axis of the insertion portion toward the inner side of the insertion portion in the fitted state,
Even when the support shaft is in a state of maximum return movement, the support shaft can be brought into contact with the insertion portion, elastically deforming the insertion portion radially outward, and the tip side of the support shaft can be inserted into the insertion portion to achieve the fitted state;
When the mated state is achieved, when a predetermined starting point provided on the other of the locking portion and the locked portion reaches the inclined surface provided on one of the locking portion and the locked portion, the other of the locking portion and the locked portion moves along the inclined surface relative to the inclined surface due to a restoring force generated in the elastically deformed insertion portion with the packing portion in contact with the contact target portion, and the support shaft moves in the forward movement direction in accordance with this movement, thereby achieving the mated state ,
A drain plug device characterized in that when the support shaft is in a state where it has moved back to its maximum extent, when the locking portion is not locked against the locked portion when the support shaft is moved back, and when the insertion portion is placed on the tip side of the support shaft, most or all of the packing portion is separated from the contact target portion .

According to the above-mentioned method 1, when the drain outlet is closed in the fitted state, the support shaft is positioned in a position before the maximum return position, maintaining a state in which a retraction force is transmitted from the retraction force applying portion to the lid portion via the locking portion and the locked portion, and the packing portion is pressed against the contact target portion. Therefore, when the drain outlet is closed, good watertightness can be achieved even when the water level is low and the water pressure applied to the plug lid is low.

Meanwhile, when the support shaft reaches its maximum reciprocating position without the plug cap attached, it is positioned further back than the position it is in when the drain outlet is closed. However, according to the above-mentioned method 1, even when the support shaft is positioned in this position, it is possible to achieve an engaged state by contacting the support shaft with the insertion portion, elastically deforming the insertion portion radially outward, and inserting the tip of the support shaft into the insertion portion. Therefore, whether the support shaft is in a forward or backward moving state (i.e., regardless of where the support shaft is positioned), the engaged state (i.e., the plug cap is properly attached to the support shaft) can be achieved simply by pushing the plug cap toward the support shaft and inserting the tip of the support shaft into the insertion portion. This increases the ease of achieving the engaged state, improving workability and usability.

Furthermore, according to the above-mentioned method 1, when the support shaft is inserted into the insertion portion to achieve the mated state, when a predetermined starting point on the other of the locking portion and the locked portion reaches the inclined surface on one of the locking portion and the locked portion, the restoring force generated by the elastically deformed insertion portion causes the other of the locking portion and the locked portion to move along the inclined surface relative to the inclined surface while the packing portion is in contact with the contact target portion. This movement then causes the support shaft to move in the forward direction, achieving the mated state. Therefore, simply inserting the support shaft into the insertion portion to the extent that the starting point reaches the inclined surface naturally achieves the mated state. Furthermore, when the support shaft is fully returned to the original position to achieve the mated state, a repulsive force is generated in the packing portion as it contacts the contact target portion. However, since the mated state is achieved when the support shaft is inserted into the insertion portion to the extent that the starting point reaches the inclined surface, the pushing force required to counter this repulsive force on the closure cap to achieve the mated state can be relatively small. As a result, achieving the mated state is made even easier.

Furthermore, according to the above-mentioned means 1 , when the support shaft is in the maximum return position, the locking portion is not locked with the locking portion during the return movement of the support shaft (in other words, the locking portion does not pass over the locking portion along the insertion direction of the support shaft relative to the insertion portion), and the insertion portion is placed on the tip side of the support shaft, most or all of the packing portion is separated from the contact target portion. Therefore, when the lid is simply placed on the support shaft, water cannot be stored in the tank body. This makes it easier for users to notice that the lid is improperly attached to the support shaft, and more reliably prevents use in an improperly attached state. Furthermore, as described in the above-mentioned effect of means 1, it is easy to return the improper attachment state to the proper state (i.e., the fitted state).

The "pulling force" may be an elastic force (for example, a spring force), a magnetic force, gravity, etc. Furthermore, the "cylindrical" shape of the insertion part includes not only a cylindrical shape that is continuous in the circumferential direction, but also a cylindrical shape in which a plurality of protrusions (such as the locking pillars and guide pillars of Means 2 described later) are arranged in a ring shape, i.e., a cylindrical shape that is partially interrupted in the circumferential direction.

Means 2: A rod-shaped support shaft that can move back and forth and has a locking portion on the tip side,
a retraction force applying portion that applies a retraction force in a backward movement direction to the support shaft;
a plug cover that can open and close a drain outlet formed in the tank body in accordance with the reciprocating movement of the support shaft;
The stopper cap is
A plate-shaped lid portion,
An annular packing portion attached to the lid portion and contacting a predetermined contact target portion when the drain outlet is in a closed state;
a cylindrical insertion portion provided on the back side of the lid portion and through which the tip end side of the support shaft is inserted;
a locked portion provided in the insertion portion and configured to be able to lock the locking portion of the support shaft inserted into the insertion portion,
When the tip side of the support shaft is inserted into the insertion portion and the locking portion is locked with the locked portion when the support shaft returns, the state is called an engaged state.
When the drain outlet is closed in the fitted state, the support shaft is positioned in a position before the maximum return position due to the contact of the packing portion with the contact object portion, thereby maintaining a state in which a retraction force is transmitted from the retraction force application portion to the lid portion via the engaged portion and the engaging portion, and the packing portion is pressed against the contact object portion.
At least one of the locking portion and the locked portion is provided with an inclined surface that gradually moves away from the central axis of the insertion portion toward the inner side of the insertion portion in the fitted state,
Even when the support shaft is in a state of maximum return movement, the support shaft can be brought into contact with the insertion portion, elastically deforming the insertion portion radially outward, and the tip side of the support shaft can be inserted into the insertion portion to achieve the fitted state;
When the mated state is achieved, when a predetermined starting point provided on the other of the locking portion and the locked portion reaches the inclined surface provided on one of the locking portion and the locked portion, the other of the locking portion and the locked portion moves along the inclined surface relative to the inclined surface due to a restoring force generated in the elastically deformed insertion portion with the packing portion in contact with the contact target portion, and the support shaft moves in the forward movement direction in accordance with this movement, thereby achieving the mated state,
the insertion portion is formed by alternately tubularly arranging locking posts that protrude from the rear surface of the lid portion and have the locked portions, and guide posts that protrude from the rear surface of the lid portion and do not have the locked portions,
The locking post portion is configured to be elastically deformable along a radial direction of the insertion portion, with a portion connected to the lid portion as a base point,
the tip end of the support shaft is pressed against the locked portion to elastically deform the locking post portion, and the tip end of the support shaft is inserted into the insertion portion, thereby achieving the fitted state;
The drain plug device is characterized in that the plug lid has a protrusion formed at the center of the area surrounded by the insertion portion on the back surface of the lid portion.

The drain outlet may be configured so that a gap is formed between the tip surface of the support shaft and the back surface of the lid when the outlet is closed. By providing such a gap, relative movement of the lid with respect to the support shaft (for example, slight rocking of the lid with respect to the support shaft) is permitted by the amount of the gap. This improves the ability of the packing to conform to the contact surface, resulting in better watertightness.

On the other hand, when the gap is present and the support shaft is moved forward to switch the drain outlet from a closed state to an open state, the support shaft first moves forward the distance of the gap, bringing the tip surface of the support shaft into contact with the underside of the lid. As the support shaft continues to move forward in this state, the support shaft lifts the plug lid, opening the drain outlet. Therefore, when the drain outlet is switched from a closed state to an open state, the amount of forward movement (lift amount) of the plug lid is smaller than the amount of forward movement of the support shaft by the amount of the gap. Considering the drainage capacity when the drain outlet is open, it is preferable to configure the drain outlet so that the difference between the amount of forward movement of the support shaft and the amount of forward movement (lift amount) of the plug lid is as small as possible.

In this regard, according to the above-mentioned method 2 , the plug cap has a protrusion formed at the center of the area surrounded by the insertion portion on the back surface of the cap. Therefore, the tip surface of the support shaft and the back surface of the cap (protrusion) can be brought closer together, and the difference between the amount of forward movement of the support shaft and the amount of forward movement (lift amount) of the plug cap can be made smaller. This improves the drainage capacity when the drain outlet is in the open state.

On the other hand, because the protrusion is located at the center of the area surrounded by the insertion portion on the back surface of the lid, a gap can be formed between the outer portion of that area (the portion located on the insertion portion side) and the tip surface of the support shaft. Therefore, the presence of this gap allows for relative movement of the lid with respect to the support shaft (for example, slight rocking of the lid with respect to the support shaft), improving the ability of the packing to follow the contact surface. This results in better watertightness.

The insertion section is made up of alternating locking posts with locking sections and guide posts without locking sections arranged in a cylindrical shape. Therefore, compared to when locking sections are provided on all posts, the force required to insert the support shaft into the insertion section and achieve the mated state can be reduced. This makes it possible to achieve the mated state relatively smoothly, further improving workability and ease of use.

Furthermore, the provision of a guide post makes it easier to insert the support shaft into the insertion portion.

In addition, if the entire area of the back surface of the lid surrounded by the insertion portion were simply configured to protrude toward the tip surface of the support shaft in order to reduce the gap, the amount of protrusion (length) of the locking post from the back surface of the lid would be small. As a result, when elastically deforming the locking post to achieve the mating state, the force required to apply to the plug cap or the like would be extremely large, and the force variation due to manufacturing dimensional errors would be greater. However, according to the above-mentioned method 2 , the protrusion is located at the center of the area, ensuring a sufficiently large amount of protrusion (length) of the locking post from the back surface of the lid. This more reliably prevents the need to apply an extremely large force to the plug cap or the like when elastically deforming the locking post to achieve the mating state, and prevents large variations in the force required. As a result, workability and usability can be further improved.

Furthermore, compared to the case where a protrusion is provided at the tip of the support shaft, the protrusion of the above-mentioned means 2 is hidden by the insertion part and is therefore invisible or difficult to see, even when the plug cap is removed from the support shaft. Therefore, the various effects described above can be achieved without any deterioration in appearance quality.

Means 3. The drain plug device according to Means 2, characterized in that when the support shaft has moved back to its maximum extent, the locking portion is not locked with the locked portion when the support shaft moves back, and the insertion portion is placed on the tip side of the support shaft, most or all of the packing portion is configured to be separated from the contact target portion.

According to the third means, the same effects as those of the first means can be achieved.

Means 4 : The stopper cap has a metal cover portion that covers the surface of the lid portion and is fixed to the lid portion,
the cover portion includes a folded portion formed by folding back an outer edge portion of the lid portion,
The back surface of the lid portion is formed with an annular receiving portion adjacent to the edge of the folded portion and protruding beyond the folded portion in the direction of the return movement of the stopper lid within a range that is generally flush with the folded portion,
When a force in the backward direction is applied to the cap in the fitted state, the receiving portion abuts against a predetermined receiving portion corresponding portion, thereby restricting further backward movement of the cap,
A drain plug device described in any of means 1 to 3, characterized in that when the receiving portion abuts against the receiving portion corresponding portion, a gap is formed between the tip surface of the support shaft and the back surface of the lid portion.

According to the above-mentioned means 4 , the surface of the lid portion is covered with the metal cover portion, thereby improving the appearance quality of the plug closure.

The cover portion has a folded portion formed by folding back the outer edge of the lid portion, and the back surface of the lid portion has an annular receiving portion that protrudes beyond the folded portion in the direction of the lid's return movement. When a force in the return direction is applied to the lid and the receiving portion abuts (contacts) the designated receiving portion, a gap is formed between the tip surface of the support shaft and the back surface of the lid portion. Therefore, even if a large force in the return direction is applied to the lid, such as when the lid is stepped on, excessive load can be more reliably prevented from being transmitted from the lid to the support shaft. As a result, damage and deformation of the support shaft and the parts supporting it can be effectively suppressed.

In addition, because the receiving portion is a relatively large-diameter annular portion adjacent to the edge of the folded portion (i.e., located immediately inside the edge of the folded portion), a large contact area between the receiving portion and the receiving portion counterpart can be ensured. This more reliably prevents damage or deformation to the receiving portion (lid portion) and the receiving portion counterpart that may come into contact with it.

Furthermore, when a force in the backward direction is applied to the closure, the receiving portion abuts against the receiving portion counterpart before the folded portion abuts against the component or tank body that constitutes the receiving portion counterpart. This more reliably prevents the metal folded portion from abutting against the component or tank body. As a result, damage to the component or tank body that would otherwise be caused by abutment with the folded portion can be more reliably prevented.

In addition, the receiving portion protrudes beyond the folded portion in the direction of the closure's return movement, while remaining roughly flush with the folded portion. In other words, the step between the folded portion and the receiving portion is very small (e.g., 1 mm or less). This allows for the aforementioned benefits of providing the receiving portion while also achieving better appearance quality and easier cleaning.

10 is a cross-sectional view of the drain plug device when the drain outlet is in a closed state in an engaged state. FIG. 10 is a partially enlarged cross-sectional view showing the support shaft and the insertion portion when the drain outlet is in a closed state in the fitted state. FIG. FIG. FIG. FIG. 10 is a cross-sectional view of the drain plug device when a downward force is applied to the plug cover while the drain outlet is in a closed state. FIG. 10 is a partially enlarged cross-sectional view showing the receiving portion and other parts when a downward force is applied to the plug cover when the drain outlet is in a closed state. FIG. 10 is a cross-sectional view of the drain plug device with the insertion portion placed on the support shaft. FIG. 10 is a partially enlarged cross-sectional view showing the support shaft, the insertion portion, and the like in a state in which the insertion portion is placed on the support shaft. FIG. 10 is a cross-sectional view of the drain plug device when the insertion portion is elastically deformed and the support shaft is inserted into the insertion portion. FIG. 10 is a partially enlarged cross-sectional view showing the support shaft and the insertion portion when the insertion portion is elastically deformed and the support shaft is inserted into the insertion portion. FIG. 10 is a cross-sectional view of the drain plug device when the support shaft moves forward using the support shaft side inclined surface and the rear side inclined surface. FIG. 10 is a partially enlarged cross-sectional view showing the support shaft and the insertion portion when the support shaft moves forward using the support shaft-side inclined surface and the rear-side inclined surface. FIG. FIG. 10 is a cross-sectional view of a drain plug device provided with a protrusion in another embodiment. FIG. 10 is a partially cutaway perspective view showing a protrusion and the like in another embodiment. 10 is a cross-sectional view of a drain plug device for illustrating a contact target portion and a receiving portion corresponding portion in another embodiment. FIG.

One embodiment will be described below with reference to the drawings. As shown in Figure 1, the drain plug device 1 is attached to a bathtub 100, which serves as a tank body. The bathtub 100 has a bottom surface 101 that forms the bottom surface of the bathtub, and a drain port 102 is formed through the bottom surface 101.

The drain plug device 1 comprises a drain outlet member 2, piping 3, an attachment member 4, a release wire 5, a support shaft mechanism 6, and a plug lid 7.

The drain outlet member 2 is cylindrical and is inserted into the drain outlet 102 so that its central axis is approximately aligned with the central axis of the drain outlet 102. The drain outlet member 2 has a flange 21 that protrudes radially outward from its upper end, and a male thread 22 formed on the outer periphery below the flange 21.

The piping 3 forms the flow path for wastewater flowing through the drain outlet 102, and is a pipe with at least the upper part being cylindrical. The piping 3 has a female threaded portion 31 on the inner periphery of its upper end, into which the male threaded portion 22 can be threaded. The piping 3 is then positioned below the bottom surface 101 so that it is approximately coaxial with the drain outlet 102. The drain outlet member 2 is then inserted into the drain outlet 102 and the piping 3 from above the bottom surface 101, and the male threaded portion 22 is threaded into the female threaded portion 31. The bottom surface 101 is then sandwiched between the flange portion 21 and the upper end surface of the piping 3, connecting the drain outlet member 2 and the piping 3, and both are attached to the bathtub 100.

In this embodiment, annular sealing members 8 and 9 made of an elastically deformable material (e.g., resin, rubber, etc.) are disposed between the flange 21 and the surface (upper surface) of the bottom portion 101, and between the upper end surface of the piping 3 and the back surface (lower surface) of the bottom portion 101. These sealing members 8 and 9 prevent water leakage between the drain outlet member 2, piping 3, and the bathtub 100.

The attachment member 4 is used to hold the support shaft mechanism 6 inside the drainage flow path, i.e., the drain outlet member 2 and the piping 3. The attachment member 4 includes an outer ring portion 41, a connecting portion 42, and a holding portion 43.

The outer ring portion 41 has a circular ring shape and functions as an attachment portion for the attachment member 4 to the drain outlet member 2 and the piping 3. In this embodiment, the outer ring portion 41 is attached to the drain outlet member 2 by, for example, placing it on a step provided on the inner circumference of the drain outlet member 2. The outer ring portion 41 (attachment member 4) may be attached to the inner portion of the piping 3, or it may be attached to the inner portions of both the drain outlet member 2 and the piping 3.

The connecting portions 42 connect the inner circumferential surface of the outer ring portion 41 and the outer circumferential surface of the retaining portion 43, and multiple connecting portions 42 (e.g., four evenly spaced apart) are provided at intervals along the circumferential direction of the retaining portion 43. The wastewater flows downstream through the gaps between each connecting portion 42. The number and shape of the connecting portions 42 may be modified as appropriate.

The holding portion 43 is cylindrical overall and holds the support shaft mechanism 6 on its inner periphery.

The release wire 5 transmits the driving force generated by the displacement of a specific operating unit (such as an operating button) to the support shaft 61 (described below) of the support shaft mechanism 6. The release wire 5 comprises a transmission member 51 made of a wire or the like, and a long, cylindrical tube member 52 made of resin or the like. The transmission member 51 is disposed on the inner periphery of the tube member 52 and is capable of reciprocating movement relative to the tube member 52.

The operating device (not shown) comprising the operating unit is provided with a locking mechanism (e.g., a thrust lock mechanism) (not shown) for locking the transmission member 51 in a forward movement (movement from the operating unit side toward the support shaft mechanism 6) position, thereby locking the transmission member 51 and, by extension, the support shaft 61 (described below) in a forward (upward) movement position.

The support shaft mechanism 6 is a mechanism for moving the plug lid 7 up and down. As shown in Figure 3, the support shaft mechanism 6 includes a support shaft 61 located on the inner periphery, a cylindrical case portion 62 located on the outer periphery of the support shaft 61, a closing portion 63 that closes the opening at the lower end of the case portion 62, and a return spring 64 that is provided between the outer periphery of the support shaft 61 and the inner periphery of the case portion 62 and is elastically deformable along the longitudinal direction of the support shaft 61. In this embodiment, the return spring 64 constitutes the "retraction force applying portion."

The support shaft 61 is a rod-shaped part that supports the stopper cap 7. The support shaft 61 is configured so that its tip portion (upper portion) protrudes from the case portion 62, and this tip portion is provided with a shoulder portion 611, a neck portion 612, and a head portion 613, in this order, toward the tip of the support shaft 61.

The shoulder 611 is tapered, with the outer diameter gradually decreasing toward the tip of the support shaft 61. The maximum outer diameter of the shoulder 611 is larger than the maximum outer diameter of the head 613. The neck 612 is cylindrical and has a constant outer diameter along the longitudinal direction of the support shaft 61. The head 613 bulges outward more than the neck 612, and most of it, except for the top, is formed with a larger diameter than the neck 612.

In addition, in this embodiment, the locking portion 614 is formed by a portion of the head 613 that protrudes outward beyond the neck 612. The locking portion 614 has a shape that extends continuously circumferentially around the support shaft 61. The locking portion 614 is locked to the locked portion 7411 (described below), thereby preventing the support shaft 61 from slipping out of the insertion portion 74 (described below), causing the stopper cap 7 to come off the support shaft 61.

In addition, the locking portion 614 is continuous with the neck portion 612 and has a support shaft-side inclined surface 614a whose outer diameter gradually increases toward the tip (upward) of the support shaft 61. The support shaft-side inclined surface 614a can also be said to be shaped so that it gradually moves away from the central axis CL of the insertion portion 74 toward the back of the insertion portion 74 in the engaged state described below. The support shaft-side inclined surface 614a serves to make it relatively easy to remove the plug lid 7 (particularly the insertion portion 74) from the support shaft 61, for example, when cleaning the inside of the drain outlet 102 or its surrounding areas (the bottom surface 101, drain outlet member 2, piping 3, etc.).

In addition, in this embodiment, the end of the support shaft side inclined surface 614a located on the tip side of the support shaft 61 constitutes the support shaft side starting portion 614b.

The support shaft 61 also has an absorber spring 615 and a center cylinder 616 inside.

The absorber spring 615 is made of a specific spring and is elastically deformable in the direction of movement (up and down) of the support shaft 61. When the drain outlet 102 is open (when the support shaft 61 is moving forward), if a large downward force is applied to the plug lid 7 (for example, when the plug lid 7 is stepped on), the absorber spring 615 compresses and deforms, preventing excessive load from being applied to the transmission member 51, etc. However, the absorber spring 615 is configured so that compressive deformation hardly occurs when the plug lid 7 is attached to the support shaft 61 (this attachment will be described later). Note that Figure 1 and other figures show only the cross sections of the absorber spring 615 and return spring 64, respectively, in a schematic manner.

The middle cylinder 616 has a cylindrical shape with a closed tip (upper end) and is capable of reciprocating (up and down) movement along the outer surface of the thin cylinder portion 63a (described below) located on its inner periphery. The end of the transmission member 51 is inserted into the middle cylinder 616.

In this embodiment, the support shaft 61 operates as follows in response to operation of the operating unit. That is, when the transmission member 51 moves forward by operating (e.g., pressing) the operating unit, the transmission member 51 pushes up the center cylinder 616 and, ultimately, the support shaft 61 against the force of the return spring 64. When the operation on the operating unit is released with the support shaft 61 moving forward to a position above a certain position, the support shaft 61 moves slightly downward, and the locking mechanism locks the transmission member 51 in the forward movement state. As a result, the support shaft 61 is locked in the forward (upward) movement state.

On the other hand, if the operating unit is operated again in this state, the transmission member 51 moves forward again, and as a result, the lock on the transmission member 51 by the locking mechanism is released. Then, when the operation on the operating unit is released, the support shaft 61 moves back (downward) together with the transmission member 51 due to the return spring 64, gravity, etc.

In this embodiment, each time the operating unit is operated, the support shaft 61 is alternately locked in a forward (upward) movement state and then released from the lock, causing the support shaft 61 to move backward (downward).

The case portion 62 has a larger diameter than the support shaft 61 and holds the support shaft 61 in a state where it can move back and forth (up and down) within itself. The case portion 62 itself is held immovably by a holding portion 43 arranged on its outer periphery.

The blocking portion 63 has a cylindrical thin tube portion 63a extending in the longitudinal direction of the support shaft 61. The thin tube portion 63a is arranged on the inner periphery of the middle tube 616 and guides the movement of the middle tube 616. Furthermore, the lower end of the blocking portion 63, where the base end of the thin tube portion 63a is connected, has a larger diameter than the thin tube portion 63a and is attached to the lower end of the case portion 62. As a result, the lower opening of the case portion 62 is closed by the blocking portion 63.

The blocking portion 63 also holds the end of the tube member 52. This connects the release wire 5 to the support shaft mechanism 6.

The return spring 64 is provided in a compressed state and applies a retracting force to the support shaft 61 in the return direction. In this embodiment, the retracting force is applied to the support shaft 61 by the elastic force generated by the return spring 64.

Returning to Figure 1, the plug lid 7 is a plug for opening and closing the drain outlet 102. The plug lid 7 comprises a lid portion 71 made of a specified resin or the like, a cover portion 72 that covers the lid portion 71, a guide portion 73 that protrudes from the back surface of the lid portion 71, an insertion portion 74 that is provided closer to the center of the back surface of the lid portion 71 than the guide portion 73, and an annular gasket portion 75 that is attached to the outer periphery of the back surface of the lid portion 71.

The lid portion 71 has a disk-like shape with an upper surface that bulges upward. The back surface of the lid portion 71 is formed with an annular receiving portion 71a that is adjacent to the edge of a folded portion 72a (described later) of the cover portion 72 (i.e., located immediately inside the edge of the folded portion 72a) and is located closer to the center of the back surface of the lid portion 71 than the folded portion 72a. When viewed from the bottom, the receiving portion 71a is located outside the outermost periphery of the packing portion 75 and protrudes further in the direction of return movement of the stopper lid 7 (i.e., downward) than the folded portion 72a. However, the receiving portion 71a protrudes further in the direction of return movement of the stopper lid 7 than the folded portion 72a within a range that is generally flush with the underside of the folded portion 72a. In other words, the step from the underside of the folded portion 72a to the receiving portion 71a is very small (e.g., 1 mm or less).

The portion of the lid 71 surrounded by the insertion portion 74, i.e., the portion positioned opposite the tip surface of the support shaft 61, is flat. At least when the drain outlet 102 is closed, a gap is formed between the portion of the lid 71 surrounded by the insertion portion 74 and the tip surface of the support shaft 61.

The cover portion 72 is made of a thin metal plate and covers the surface of the lid portion 71 to enhance the appearance of the stopper cap 7. The cover portion 72 has a folded portion 72a that is folded back at the outer edge of the lid portion 71, and is fixed to the lid portion 71 by this folded portion 72a.

The guide portion 73 is arranged on the outer periphery of the holding portion 43 and moves along the outer periphery of the holding portion 43 as the support shaft 61 moves back and forth (up and down). The guide portion 73 is provided to prevent the stopper cap 7 from tilting or shifting horizontally as it moves back and forth.

The insertion portion 74 is a cylindrical portion through which the tip of the support shaft 61 is inserted, and functions as the attachment portion of the plug lid 7 relative to the support shaft 61. As shown in Figures 4 and 5, the insertion portion 74 is composed of alternating cylindrical locking posts 741 and guide posts 742 that protrude from the back surface of the lid portion 71. In this embodiment, three locking posts 741 and three guide posts 742 are provided.

Each locking post 741 has an inwardly protruding locked portion 7411. The locked portion 7411 is the portion where the locking portion 614 of the support shaft 61 inserted into the insertion portion 74 is locked. In this embodiment, the state in which the tip side of the support shaft 61 is inserted into the insertion portion 74 and the locking portion 614 is locked to the locked portion 7411 when the support shaft 61 moves back (downward) is referred to as the "engaged state" (the state shown in Figures 1 and 2).

As shown in Figure 2, the inner peripheral surface of the engagement portion 7411 includes a front inclined surface 7411a whose inner diameter gradually decreases toward the back of the insertion portion 74, an intermediate surface 7411b having a constant inner diameter along the central axis of the insertion portion 74, and a rear inclined surface 7411c whose inner diameter gradually increases toward the back of the insertion portion 74.

The front inclined surface 7411a is provided to facilitate insertion of the support shaft 61 into the insertion portion 74. On the other hand, the rear inclined surface 7411c, like the support shaft inclined surface 614a, functions to make it relatively easy to remove the plug cap 7 (insertion portion 74) from the support shaft 61, for example, when cleaning the plug cap 7. It can also be said that the rear inclined surface 7411c is shaped so that, in the engaged state, it gradually moves away from the central axis of the insertion portion 74 toward the rear of the insertion portion 74. In this embodiment, the support shaft inclined surface 614a and the rear inclined surface 7411c each correspond to an "inclined surface."

In addition, in this embodiment, the end of the front inclined surface 7411a located on the far side of the insertion portion 74 (the boundary between the front inclined surface 7411a and the intermediate surface 7411b) constitutes the insertion portion side starting point 7411d. In this embodiment, the support shaft side starting point 614b and the insertion portion side starting point 7411d each correspond to a "starting point."

Furthermore, the locking post portion 741 is capable of elastic deformation in the radial direction of the insertion portion 74, starting from the portion where it connects to the lid portion 71.

Unlike the locking column portion 741, the guide column portion 742 does not have a locked portion 7411. The inner surface of the guide column portion 742 is smooth, and its role is to guide the relative movement of the support shaft 61 with respect to the insertion portion 74 when the support shaft 61 is inserted into the insertion portion 74.

Returning to Figure 1, the packing portion 75 is an annular component made of an elastically deformable material (e.g., resin, rubber, etc.). In this embodiment, a gap K is formed between the outer peripheral portion of the packing portion 75 and the back surface of the lid portion 71. The outer peripheral portion of the packing portion 75 is elastically deformable toward the gap K.

In this embodiment, when the drain outlet 102 is in the closed state, operating the operating unit causes the support shaft 61 to move forward (upward), causing the packing portion 75 to move away from the drain outlet member 2. The locking mechanism then maintains the support shaft 61 and plug lid 7 in the forward (upward) state, thereby maintaining the drain outlet 102 in the open state.

On the other hand, when the drain outlet 102 is in the open state, if the locking mechanism is released by operating the operating part, the support shaft 61 moves back (down) due to the retraction force applied by the return spring 64, etc. Then, as the support shaft 61 moves back (down), the plug lid 7 moves back (down), and the entire outer periphery of the packing portion 75 comes into contact with the drain outlet member 2, closing the drain outlet 102. In this embodiment, the inner surface (inclined surface) of the drain outlet member 2, which faces the outer periphery of the packing portion 75 in the direction of reciprocating movement of the plug lid 7 and gradually slopes downward toward the central axis of the drain outlet member 2, forms a contact target portion 23 (see Figure 1, etc.) that comes into contact with the packing portion 75 when the drain outlet 102 is in the closed state.

When the drain outlet 102 is closed in the fitted state (the state shown in Figures 1 and 2, etc.), the support shaft 61 is positioned in a position before its maximum return position due to contact of the packing portion 75 with the drain outlet member 2 (contact target portion 23). In other words, a gap S is formed between the support shaft 61 and the blocking portion 63 located below it (see Figure 1). As a result, when the drain outlet 102 is closed, a retraction force is transmitted from the return spring 64 to the lid portion 71 via the engaged portion 7411 and the engaging portion 614, and the packing portion 75 is pressed against the drain outlet member 2.

When the drain outlet 102 is closed in the fitted state, if a relatively large force is applied to the plug lid 7 in the return direction (downward), such as by stepping on the plug lid 7, the outer peripheral portion of the packing portion 75 elastically deforms toward the gap K, causing the support shaft 61 and the plug lid 7 to sink. At this time, the receiving portion 71a abuts the drain outlet member 2, while the folded portion 72a does not abut the drain outlet member 2 (see Figures 6 and 7). Even when the receiving portion 71a abuts the drain outlet member 2, a gap remains between the tip surface of the support shaft 61 and the back surface of the cover portion 71. In this embodiment, the upper surface of the drain outlet member 2, including the upper surface of the flange portion 21, which faces the receiving portion 71a in the reciprocating direction of the plug lid 7, forms a receiving portion corresponding portion 24 (see Figure 1, etc.) that abuts against the receiving portion 71a when the plug lid 7 or the like sinks.

In addition, in this embodiment, by configuring the outer peripheral portion of the packing portion 75 to be elastically deformable relatively greatly toward the gap K and adjusting the positions of the locking portion 614 and the locked portion 7411, it is possible to achieve the fitted state by inserting the tip end of the support shaft 61 into the insertion portion 74 while elastically deforming the insertion portion 74, even when the support shaft 61 has moved back to its fullest extent (see Figure 8). Next, we will explain how to achieve the fitted state when the support shaft 61 has moved back to its fullest extent, such as when installing the drain plug device 1 or after cleaning the plug cover 7.

When the support shaft 61 is in the fully retracted state and the mated state is achieved, first, as shown in Figures 8 and 9, the holding portion 43 is inserted into the guide portion 73, and the front inclined surface 7411a is placed on the head portion 613. By inserting the holding portion 43 into the guide portion 73, the central axes of the support shaft 61 and the insertion portion 74 become approximately parallel.

When the front inclined surface 7411a is placed on the head 613, i.e., when the support shaft 61 has moved to its maximum extent, the locking portion 614 is not locked with the locked portion 7411 when the support shaft 61 is moved back, and the insertion portion 74 is placed on the tip side of the support shaft 61, most or all of the packing portion 75 is separated from the drain outlet member 2. In this embodiment, when the central axes of the support shaft 61 and the insertion portion 74 are aligned, the entire packing portion 75 is separated from the drain outlet member 2. When the central axis of the insertion portion 74 is slightly tilted relative to the central axis of the support shaft 61, part of the packing portion 75 is in contact with the drain outlet member 2, while most of the packing portion 75 is separated from the drain outlet member 2.

Next, with the front inclined surface 7411a placed on the head 613, a downward force is applied to the lid 7, for example by manually pushing the lid 7 downward. In this embodiment, in order to achieve the mated state when the support shaft 61 has fully returned to its original position, it is necessary to apply a force to the lid 7 that is greater than the force exerted by the water pressure from the water stored in the bathtub 100. In other words, the engagement allowance of the locking portion 614 relative to the locked portion 7411 is set so that the locking portion 614 cannot pass through the locked portion 7411 unless a force sufficiently greater than the force exerted by the water pressure from the water stored in the bathtub 100 is applied, and the locking force of the locking portion 614 relative to the locked portion 7411 is sufficiently large.

More specifically, "water pressure applied from the water stored in the bathtub 100" can be defined as the force of water pressure that can be applied to the plug lid 7 when water is stored in the bathtub 100 with the drain outlet 102 closed. For example, when the bathtub 100 is full, the water pressure applied to the plug lid 7 from the water stored in the bathtub 100 is approximately 10 N. Of course, this water pressure will vary depending on the capacity and shape of the bathtub 100, the shape and size of the plug lid 7, etc.

Now, as a downward force is applied to the plug lid 7, the tip side (head 613) of the support shaft 61 presses against the locked portion 7411 (front inclined surface 7411a), causing the insertion portion 74 (particularly the locking post portion 741) to elastically deform radially outward, while the support shaft 61 is inserted into the insertion portion 74. Then, when the support shaft 61 is inserted to a certain extent into the insertion portion 74, the entire outer peripheral surface of the packing portion 75 comes into contact with the drain outlet member 2.

As shown in Figures 10 and 11, when the support shaft 61 is further inserted into the insertion portion 74, the support shaft-side starting point 614b reaches the rear-side inclined surface 7411c, and the insertion portion-side starting point 7411d reaches the support shaft-side inclined surface 614a. At this stage, with the gasket portion 75 in contact with the drain outlet member 2, the restoring force generated by the elastically deformed insertion portion 74 causes the locking portion 614 to move along the rear-side inclined surface 7411c relative to the rear-side inclined surface 7411c. Furthermore, the locked portion 7411 moves along the support shaft-side inclined surface 614a relative to the support shaft-side inclined surface 614a.

As a result of this movement, the support shaft 61 moves in its forward movement direction (upward) as shown in Figures 12 and 13. As a result, the mated state is achieved. Furthermore, after achieving the mated state, by releasing the downward force on the plug lid 7 (for example, by releasing the hand from the plug lid 7), the restoring force generated by the elastically deformed packing portion 75 causes the support shaft 61 to move further forward, ultimately reaching the state shown in Figure 1.

As described above in detail, according to this embodiment, when the drain outlet 102 is closed in the fitted state, the support shaft 61 is positioned in a position before its maximum return position, maintaining a state in which a retraction force is transmitted from the return spring 64 to the lid portion 71 via the locking portion 614 and the locked portion 7411, and the packing portion 75 is pressed against the drain outlet member 2. Therefore, when the drain outlet 102 is closed, good watertightness can be achieved even when the water level is low and the water pressure applied to the plug lid 7 is low.

Meanwhile, when the support shaft 61 reaches its maximum reciprocating position, it is positioned further back than the position it is in when the drain outlet 102 is closed. However, in this embodiment, even when the support shaft 61 is positioned in this position, the mated state can be achieved by contacting the support shaft 61 with the insertion portion 74, elastically deforming the insertion portion 74 radially outward, and inserting the tip of the support shaft 61 into the insertion portion 74. Therefore, whether the support shaft 61 is in a forward or backward moving state (i.e., regardless of where the support shaft 61 is positioned), the mated state (i.e., the state in which the plug lid 7 is properly attached to the support shaft 61) can be achieved simply by pushing the plug lid 7 toward the support shaft 61 and inserting the tip of the support shaft 61 into the insertion portion 74. This increases the ease of achieving the mated state, improving the ease of installation of the drain plug device 1 and the ease of use (e.g., cleaning) of the drain plug device 1.

Furthermore, when the support shaft 61 is inserted through the insertion portion 74 to achieve the fitted state, when a predetermined starting point (insertion portion-side starting point 7411d or support shaft-side starting point 614b) on the other of the locking portion 614 and the locked portion 7411 reaches the inclined surface (support shaft-side inclined surface 614a or rear inclined surface 7411c) on one of the locking portion 614 and the locked portion 7411, the restoring force generated by the elastically deformed insertion portion 74 moves the locking portion 614 and the locked portion 7411 along the inclined surfaces 614a, 7411c while the packing portion 75 is in contact with the drain outlet member 2. This movement then moves the support shaft 61 in the forward direction (upward), thereby achieving the fitted state. Therefore, the mated state can be achieved naturally by simply inserting the support shaft 61 into the insertion portion 74 so that the starting points 7411d, 614b reach the inclined surfaces 614a, 7411c. Furthermore, when the support shaft 61 is fully retracted to achieve the mated state, a repulsive force is generated in the packing portion 75 as it comes into contact with the drain outlet member 2. However, since the mated state is achieved by inserting the support shaft 61 into the insertion portion 74 so that the starting points 7411d, 614b reach the inclined surfaces 614a, 7411c, the pushing force that must be applied to the plug lid 7 against this repulsive force to achieve the mated state can be made relatively small. As a result, achieving the mated state is made even easier.

Furthermore, when a force is applied to the plug lid 7 in the backward direction and the receiving portion 71a abuts against the drain outlet member 2 (receiving portion corresponding portion 24), a gap can be formed between the tip surface of the support shaft 61 and the back surface of the lid portion 71. Therefore, even if a large force is applied to the plug lid 7 in the backward direction, such as when the plug lid 7 is stepped on, excessive load can be more reliably prevented from being transmitted from the plug lid 7 to the support shaft 61. As a result, damage and deformation of the support shaft 61 and the parts that support it (attachment member 4) can be effectively suppressed.

In addition, because the receiving portion 71a is a relatively large-diameter annular portion adjacent to the edge of the folded portion 72a, a large contact area between the receiving portion 71a and the drain outlet member 2 (receiving portion corresponding portion 24) can be ensured. This more reliably prevents damage or deformation of the receiving portion 71a (lid portion 71) and the drain outlet member 2 (receiving portion corresponding portion 24) that may come into contact with it.

In addition, because the receiving portion 71a protrudes further in the direction of return movement (downward) of the plug lid 7 than the folded portion 72a, when a force in the return direction is applied to the plug lid 7, the resin receiving portion 71a abuts against the drain outlet member 2 (receiving portion corresponding portion 24) before the folded portion 72a abuts against the drain outlet member 2 that constitutes the receiving portion corresponding portion 24. This more reliably prevents the metal folded portion 72a from abutting against the drain outlet member 2. As a result, damage to the drain outlet member 2 due to abutment with the folded portion 72a can be more reliably prevented.

Furthermore, although the receiving portion 71a, which functions as described above, protrudes further in the direction of the return movement of the plug lid 7 than the folded portion 72a, it is generally flush with the folded portion 72a (its underside). Therefore, while achieving the above-mentioned effects of providing the receiving portion 71a, it is possible to achieve better appearance quality and easier cleaning.

The provision of the receiving portion 71a also functions effectively when the support shaft 61 is in the fully reciprocated state to achieve the mated state. In other words, even when the lid 7 is pushed downward onto the support shaft 61 to attach it, excessive load is prevented from being transmitted from the lid 7 to the support shaft 61, and the metal folded portion 72a is prevented from coming into contact with the drain outlet member 2. Therefore, when attaching the lid 7 to the support shaft 61, damage to the support shaft 61 or attachment member 4 due to the pushing force can be effectively suppressed, and damage to the drain outlet member 2 due to the folded portion 72a can be more reliably prevented.

In addition, in this embodiment, when the support shaft 61 has fully returned, the locking portion 614 is not locked with the locked portion 7411 during the support shaft 61's return movement, and the insertion portion 74 is placed on the tip of the support shaft 61 (for example, as shown in Figures 8 and 9), most or all of the packing portion 75 is separated from the drain outlet member 2. Therefore, when the plug lid 7 is simply placed on the support shaft 61, water cannot be stored in the bathtub 100. This makes it easier for users to notice that the plug lid 7 is improperly attached to the support shaft 61, and more reliably prevents the bathtub from being used in an improperly attached state. As described above, returning an improper attachment state to the appropriate state (i.e., the aforementioned engaged state) can be easily achieved.

Furthermore, in order to achieve the mated state when the support shaft 61 has fully moved back, a force greater than the water pressure applied to the lid 7 from the water stored in the bathtub 100 must be applied. In other words, the engagement allowance of the locking portion 614 relative to the locked portion 7411 is set so that the locking portion 614 cannot pass through the locked portion 7411 unless a force sufficiently greater than the water pressure applied from the water stored in the bathtub 100 is applied, thereby providing a sufficiently large locking force of the locking portion 614 relative to the locked portion 7411. Therefore, compared to a configuration in which the mated state can be achieved with water pressure alone, the removal force of the lid 7 (the force required to pull the support shaft 61 from the insertion portion 74) can be significantly increased, making it less likely that the lid 7 will come off unintentionally from the support shaft 61 (the support shaft 61 will come off from the insertion portion 74). This further improves usability. Furthermore, when the drain outlet 102 is closed, the retraction force applied by the return spring 64 will not easily release the engagement of the engaging portion 614 with the engaged portion 7411. This allows a more stable retraction force to be applied to the plug lid 7 when the drain outlet 102 is closed, thereby more reliably achieving good watertightness.

Furthermore, when the drain outlet 102 is in the closed state, a gap is formed between the portion of the lid portion 71 surrounded by the insertion portion 74 and the tip surface of the support shaft 61. This gap allows for relative movement of the lid portion 71 with respect to the support shaft 61 (for example, slight rocking of the lid portion 71 with respect to the support shaft 61). This improves the ability of the gasket portion 75 to follow the drain outlet member 2, resulting in better watertightness.

The insertion portion 74 is made up of alternating locking posts 741, each with a locking portion 7411, and guide posts 742, each without a locking portion 7411, arranged in a cylindrical shape. Therefore, compared to when locking portions 7411 are provided on all posts, the force required to insert the support shaft 61 into the insertion portion 74 and achieve the mated state can be reduced. This makes it possible to achieve the mated state relatively smoothly, further improving workability and ease of use.

In addition, the guide post portion 742 makes it easier to insert the support shaft 61 into the insertion portion 74.

Note that the present invention is not limited to the above-described embodiment, and may be implemented, for example, as follows. Of course, other applications and modifications not exemplified below are also possible.

(a) In the above embodiment, the portion of the plug lid 7 surrounded by the insertion portion 74 on the back surface of the lid portion 71, i.e., the portion facing the tip surface of the support shaft 61, is flat. When switching the drain outlet 102 from a closed state to an open state, the support shaft 61 first moves forward a distance equal to the gap formed between the flat portion on the back surface of the lid portion 71 and the tip surface of the support shaft 61, bringing the tip surface of the support shaft 61 into contact with the back surface of the lid portion 71. As the support shaft 61 continues to move forward in this state, the plug lid 7 is lifted by the support shaft 61, switching the drain outlet 102 from a closed state to an open state. Therefore, when switching the drain outlet 102 from a closed state to an open state, the amount of forward movement (lift amount) of the plug lid 7 is smaller than the amount of forward movement of the support shaft 61 by the amount of the gap. Here, when considering the drainage capacity when the drain outlet 102 is in the open state, it is preferable to make the difference between the amount of forward movement of the support shaft 61 and the amount of forward movement (lift amount) of the plug lid 7 smaller, thereby ensuring a larger amount of forward movement (lift amount) of the plug lid 7.

As shown in Figures 14 and 15, the plug lid 7 may be configured with a protrusion 76 formed on the back surface of the lid portion 71, protruding from the center of the area surrounded by the insertion portion 74. In this configuration, the tip surface of the support shaft 61 and the back surface of the lid portion 71 (protrusion 76) can be brought closer together, and the difference between the amount of forward movement of the support shaft 61 and the amount of forward movement (lift amount) of the plug lid 7 can be reduced. This improves drainage capacity when the drain outlet 102 is in the open state.

On the other hand, because the protrusion 76 is located at the center of the area surrounded by the insertion portion 74 on the back surface of the lid portion 71, a gap can be formed between the outer portion of that area (the portion located on the insertion portion 74 side) and the tip surface of the support shaft 61. Therefore, as in the above embodiment, the presence of this gap allows relative movement of the lid portion 71 with respect to the support shaft 61 (for example, slight rocking of the lid portion 71 with respect to the support shaft 61), thereby improving the tracking of the gasket portion 75 with respect to the drain outlet member 2.

In addition, if the entire area of the back surface of the lid portion 71 surrounded by the insertion portion 74 were simply configured to protrude toward the tip surface of the support shaft 61 in an attempt to reduce the gap, the amount (length) of protrusion of the locking post 741 from the back surface of the lid portion 71 would be small. As a result, when elastically deforming the locking post 741 to achieve the mated state, an extremely large force would need to be applied to the plug lid 7 or the like, and there is a risk that the force would vary greatly due to manufacturing dimensional errors. However, by providing the protrusion 76 at the center of this area, it is possible to ensure a sufficiently large amount (length) of protrusion of the locking post 741 from the back surface of the lid portion 71. This more reliably prevents the need to apply an extremely large force to the plug lid 7 or the like when elastically deforming the locking post 741 to achieve the mated state, and prevents large variations in the force that needs to be applied. As a result, workability and usability can be further improved.

Furthermore, compared to when a protrusion is provided at the tip of the support shaft 61, the protrusion 76 is hidden by the insertion portion 74 and guide portion 73, making it invisible or difficult to see, even when the plug lid 7 is detached from the support shaft 61. Therefore, the various effects described above can be achieved without any degradation in appearance quality.

(b) In the above embodiment, the retracting force is applied to the support shaft 61 by the elastic force generated by the return spring 64. However, the retracting force may also be applied to the support shaft 61 by magnetic force generated by a specified magnet, or by gravity acting on the metal support shaft 61 or the plug cap 7, for example.

(c) In the above embodiment, the support shaft 61 has the support shaft-side inclined surface 614a, and the insertion portion 74 has the rear-side inclined surface 7411c. That is, in the fitted state, inclined surfaces that gradually move away from the central axis CL of the insertion portion 74 toward the rear of the insertion portion 74 are provided on both the support shaft 61 and the insertion portion 74. In contrast, in the fitted state, an inclined surface that gradually moves away from the central axis CL toward the rear of the insertion portion 74 may be provided on only one of the support shaft 61 and the insertion portion 74. For example, the support shaft 61 may have the support shaft-side inclined surface 614a, while the insertion portion 74 may have a stepped surface extending in a direction perpendicular to the central axis CL instead of the rear-side inclined surface 7411c. Alternatively, the insertion portion 74 may have a rear-side inclined surface 7411c, while the support shaft 61 may have a stepped surface that extends in a direction perpendicular to the central axis CL in the fitted state, instead of the support shaft-side inclined surface 614a.

(d) In the above embodiment, when the support shaft 61 has moved back to its maximum extent, the locking portion 614 is not locked to the locked portion 7411 when the support shaft 61 is moved back, and the insertion portion 74 is placed on the tip side of the support shaft 61, most or all of the packing portion 75 is configured to be separated from the drain outlet member 2. However, in this state, the entire outer periphery of the packing portion 75 may be configured to come into contact with the drain outlet member 2 (i.e., water can be stored in the bathtub 100).

(e) The number and shape of the locking posts 741 and guide posts 742 may be changed as appropriate. For example, two locking posts 741 and two guide posts 742 may be provided.

(f) In the above embodiment, the folded portion 72a and the drain outlet member 2 are configured to face each other in the direction of reciprocating movement of the plug lid 7. However, the outer diameter of the plug lid 7 may be larger than the outer diameter of the flange portion 21, and the folded portion 72a and the bottom surface portion 101 (bathtub 100) may be configured to face each other in the direction of reciprocating movement of the plug lid 7. In this case, it is preferable that when the plug lid 7 or the like sinks, the receiving portion 71a abuts against the "receiving portion corresponding portion formed by the upper surface of the bottom surface portion 101," so that the folded portion 72a does not abut against the bottom surface portion 101 located below it.

(g) In the above embodiment, the receiving portion 24 is formed by the drain outlet member 2, but as in (f) above, the receiving portion may be formed by something other than the drain outlet member 2. For example, as shown in FIG. 16, the receiving portion 104 that abuts against the receiving portion 71a when the plug lid 7 or the like sinks may be formed by the upper surface of the bottom portion 101 that faces the receiving portion 71a in the direction of reciprocating movement of the plug lid 7.

(h) In the above embodiment, the drain outlet 102 is configured to be closed when the plug lid 7 (packing portion 75) comes into contact with the contact target portion 23 formed by the drain outlet member 2. However, as shown in FIG. 16, the drain outlet 102 may be configured to be closed when the plug lid 7 (packing portion 75) comes into contact with the contact target portion 103 formed by the bottom surface portion 101. Note that, as shown in FIG. 16, if a drain outlet member 2 or the like is not provided, the attachment member 4 may be attached to the bathtub 100.

(i) In the above embodiment, a bathtub 100 is used as an example of a tank body, but the tank body to which the technical concept of the present invention can be applied is not limited to a bathtub. Therefore, the technical concept of the present invention may also be applied to tank bodies other than bathtubs, such as washbasins and kitchen sinks, for example.

1...Drain plug device, 7...Plug cover, 23, 103...Contact target portion, 24, 104...Receiving portion corresponding portion, 61...Support shaft, 64...Return spring (retraction force applying portion), 71...Cover portion, 71a...Receiving portion, 72a...Folded portion, 74...Insertion portion, 75...Gasket portion, 76...Protrusion, 100...Tub (tank body), 102...Drain outlet, 614...Engaging portion, 614a...Support shaft side inclined surface (inclined surface), 614b...Support shaft side starting portion (starting point portion), 741...Engaging pillar portion, 742...Guide pillar portion, 7411...Engaged portion, 7411c...Rear side inclined surface (inclined surface), 7411d...Insertion portion side starting point portion.

Claims (4)

a rod-shaped support shaft having a locking portion at its tip end and capable of reciprocating;
a retraction force applying portion that applies a retraction force in a backward movement direction to the support shaft;
a plug cover that can open and close a drain outlet formed in the tank body in accordance with the reciprocating movement of the support shaft;
The stopper cap is
A plate-shaped lid portion;
An annular packing portion attached to the lid portion and contacting a predetermined contact target portion when the drain outlet is in a closed state;
a cylindrical insertion portion provided on the back side of the lid portion and through which the tip end side of the support shaft is inserted;
a locked portion provided in the insertion portion and configured to be able to lock the locking portion of the support shaft inserted into the insertion portion,
When the tip side of the support shaft is inserted into the insertion portion and the locking portion is locked with the locked portion when the support shaft returns, the state is called an engaged state.
When the drain outlet is closed in the fitted state, the support shaft is positioned in a position before the maximum return position due to the contact of the packing portion with the contact object portion, thereby maintaining a state in which a retraction force is transmitted from the retraction force application portion to the lid portion via the engaged portion and the engaging portion, and the packing portion is pressed against the contact object portion.
At least one of the locking portion and the locked portion is provided with an inclined surface that gradually moves away from the central axis of the insertion portion toward the inner side of the insertion portion in the fitted state,
Even when the support shaft is in a state of maximum return movement, the support shaft can be brought into contact with the insertion portion, elastically deforming the insertion portion radially outward, and the tip side of the support shaft can be inserted into the insertion portion to achieve the fitted state;
When the mated state is achieved, when a predetermined starting point provided on the other of the locking portion and the locked portion reaches the inclined surface provided on one of the locking portion and the locked portion, the other of the locking portion and the locked portion moves along the inclined surface relative to the inclined surface due to a restoring force generated in the elastically deformed insertion portion with the packing portion in contact with the contact target portion, and the support shaft moves in the forward movement direction in accordance with this movement, thereby achieving the mated state ,
A drain plug device characterized in that when the support shaft is in a state where it has moved back to its maximum extent, when the locking portion is not locked against the locked portion when the support shaft is moved back, and when the insertion portion is placed on the tip side of the support shaft, most or all of the packing portion is separated from the contact target portion . a rod-shaped support shaft having a locking portion at its tip end and capable of reciprocating;
a retraction force applying portion that applies a retraction force in a backward movement direction to the support shaft;
a plug cover that can open and close a drain outlet formed in the tank body in accordance with the reciprocating movement of the support shaft;
The stopper cap is
A plate-shaped lid portion;
An annular packing portion attached to the lid portion and contacting a predetermined contact target portion when the drain outlet is in a closed state;
a cylindrical insertion portion provided on the back side of the lid portion and through which the tip end side of the support shaft is inserted;
a locked portion provided in the insertion portion and configured to be able to lock the locking portion of the support shaft inserted into the insertion portion,
When the tip side of the support shaft is inserted into the insertion portion and the locking portion is locked with the locked portion when the support shaft returns, the state is called an engaged state.
When the drain outlet is closed in the fitted state, the support shaft is positioned in a position before the maximum return position due to the contact of the packing portion with the contact object portion, thereby maintaining a state in which a retraction force is transmitted from the retraction force application portion to the lid portion via the engaged portion and the engaging portion, and the packing portion is pressed against the contact object portion.
At least one of the locking portion and the locked portion is provided with an inclined surface that gradually moves away from the central axis of the insertion portion toward the inner side of the insertion portion in the fitted state,
Even when the support shaft is in a state of maximum return movement, the support shaft can be brought into contact with the insertion portion, elastically deforming the insertion portion radially outward, and the tip side of the support shaft can be inserted into the insertion portion to achieve the fitted state;
When the mated state is achieved, when a predetermined starting point provided on the other of the locking portion and the locked portion reaches the inclined surface provided on one of the locking portion and the locked portion, the other of the locking portion and the locked portion moves along the inclined surface relative to the inclined surface due to a restoring force generated in the elastically deformed insertion portion with the packing portion in contact with the contact target portion, and the support shaft moves in the forward movement direction in accordance with this movement, thereby achieving the mated state,
the insertion portion is formed by alternately tubularly arranging locking posts that protrude from the rear surface of the lid portion and have the locked portions, and guide posts that protrude from the rear surface of the lid portion and do not have the locked portions,
The locking post portion is configured to be elastically deformable along a radial direction of the insertion portion, with a portion connected to the lid portion as a base point,
the tip end of the support shaft is pressed against the locked portion to elastically deform the locking post portion, and the tip end of the support shaft is inserted into the insertion portion, thereby achieving the fitted state;
The drain plug device is characterized in that the plug lid has a protrusion formed at the center of the area surrounded by the insertion portion on the back surface of the lid portion. The drain plug device of claim 2, characterized in that when the support shaft has moved back to its maximum extent, when the locking portion is not locked to the locked portion when the support shaft is moved back, and when the insertion portion is placed on the tip side of the support shaft, most or all of the packing portion is separated from the contact target portion . The stopper cap covers the surface of the lid portion and has a metal cover portion fixed to the lid portion,
the cover portion includes a folded portion formed by folding back an outer edge portion of the lid portion,
The back surface of the lid portion is formed with an annular receiving portion adjacent to the edge of the folded portion and protruding beyond the folded portion in the direction of the return movement of the stopper lid within a range that is generally flush with the folded portion,
When a force in the backward direction is applied to the cap in the fitted state, the receiving portion abuts against a predetermined receiving portion corresponding portion, thereby restricting further backward movement of the cap,
A drain plug device as described in any one of claims 1 to 3, characterized in that when the receiving portion abuts against the receiving portion corresponding portion, a gap is formed between the tip surface of the support shaft and the back surface of the lid portion.