WO2015182109A1

WO2015182109A1 - Liquid level detection device

Info

Publication number: WO2015182109A1
Application number: PCT/JP2015/002631
Authority: WO
Inventors: 篤安田
Original assignee: 株式会社デンソー
Priority date: 2014-05-27
Filing date: 2015-05-25
Publication date: 2015-12-03
Also published as: JP2015224937A

Abstract

According to the present invention, a first position (P1) where an outer cylinder engagement portion (44a) comes into contact with a body engagement portion (30) in conjunction with the fitting of a cover (40) to a body (20), a second position (P2) where the outer cylinder engagement portion (44a) is pressed by the body engagement portion (30) and undergoes elastic deformation, and a third position (P3) where the outer cylinder engagement portion (44a) undergoes elastic recovery and engages with the body engagement portion (30) are set. If the length of the portion where the outer cylinder (44) is fitted to a fitting peripheral wall (24, 324) is termed an outer cylinder fitting distance (SP), the length of the portion where an inner shaft (46, 246) is fitted to a fitting hole (26) defined as an inner shaft fitting distance (SS), and the distance between the first position (P1) and the third position (P3) termed an engagement distance (SE), then the outer cylinder fitting distance (SP) and/or the inner shaft fitting distance (SS) is larger than the engagement distance (SE).

Description

Liquid level detector

Cross-reference of related applications

This application is based on Japanese Patent Application No. 2014-109381 filed on May 27, 2014, the contents of which are incorporated herein by reference.

The present disclosure relates to a liquid level detection device that detects a liquid level of a liquid stored in a container.

Conventionally, a liquid level detection device for detecting a liquid level of a liquid stored in a container is known. For example, in the liquid level detection device described in Patent Document 1, a body (lid), an outer cylinder that covers a float that floats on the liquid level, and an inner shaft that houses a detection element that detects the position of the float are integrated. And a cover (housing) to be formed. And the opening part located in the upper end of a cover is liquid-tightly sealed with the body.

JP 2002-71431 A

Here, in the technique described in Patent Document 1, it is considered that the outer cylinder and the inner shaft of the cover are fitted with the body to realize liquid-tight sealing. However, in this technique, for example, when it is installed in a container such as a vehicle and vibrations act on the liquid level detection device, it is considered that wear may occur at a place where the body and the cover are fitted. And, when rattling occurs due to the wear, there is a possibility that the worst case may occur.

Therefore, the present inventor has examined a configuration in which an outer cylinder engaging portion provided in an elastically deformable manner is provided on the cover and a body engaging portion provided in an engageable manner with the outer cylinder engaging portion is provided in the body. However, in this configuration, in the assembly process of the body and the cover, if the cover is inserted slightly diagonally, unintended elastic deformation occurs in the outer cylinder engaging portion, and there is a risk that the shaft cannot be smoothly fitted. In addition, the outer cylinder engaging portion may be damaged and the yield may be reduced. As a result, it has been difficult to smoothly provide a liquid level detection device that prevents dropout.

The present disclosure has been made in view of the problems described above, and an object thereof is to provide a liquid level detection device that prevents dropout.

In order to achieve the above object, according to one aspect of the present disclosure, in a liquid level detection device that detects a liquid level of a liquid stored in a container, the liquid level detection apparatus can be assembled to the container in a predetermined fitting direction. A body having a fitting peripheral wall that forms a peripheral wall surface along the inner periphery, a fitting hole provided on the inner peripheral side of the fitting peripheral wall, and a cover that is fitted to the body, and is fitted along the fitting direction. A cover integrally forming an outer cylinder fitted to the peripheral wall and an inner shaft fitted into the fitting hole along the fitting direction on the inner circumferential side of the outer cylinder; and the outer cylinder and the inner shaft And a float that floats on the liquid and a detection element that is inserted into the inner shaft and detects the position of the float, and the outer cylinder has an outer cylinder engaging portion that is provided so as to be elastically deformable. Has a body engaging part that can be engaged with the outer cylinder engaging part, and fits the cover to the body Thus, the first position where the outer cylinder engaging portion comes into contact with the body engaging portion, the second position where the outer cylinder engaging portion is pressed and elastically deformed by the body engaging portion, and the outer cylinder engaging portion is elastically restored. The third position for engaging with the body engaging portion is set, and the distance at which the outer cylinder is fitted with the fitting peripheral wall is defined as the outer cylinder fitting distance, and the inner shaft is fitted with the fitting hole. When the distance between the first position and the third position is defined as the engagement distance, at least one of the outer cylinder engagement distance and the inner shaft engagement distance is It is characterized by being larger than the combined distance.

Thus, according to at least one of the outer cylinder fitting distance and the inner shaft fitting distance larger than the engagement distance, when the cover is fitted to the body along a predetermined fitting direction, Prior to the contact between the tube engaging portion and the body engaging portion, at least one of the fitting between the outer tube and the fitting peripheral wall and the fitting between the inner shaft and the fitting hole is started. Then, with the fitting of the cover to the body, after the outer cylinder engaging portion comes into contact with the body engaging portion at the first position, the outer cylinder engaging portion is pressed by the body engaging portion at the second position. The outer cylinder engaging portion is then elastically restored and engaged with the body engaging portion at the third position. According to this, after the cover is guided so as to be assembled along the fitting direction, the outer tube engaging portion is elastically deformed, so that the assembly can be performed smoothly. Further, since the body and the cover are fitted on the inner peripheral side and the outer peripheral side, respectively, the holding force of the cover is increased and the vibration is restricted, so that the cover can be prevented from falling off the body. As described above, it is possible to provide a liquid level detection device that prevents dropping.

The above and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings. The drawing
It is a figure which shows the state in which the liquid level detection apparatus in 1st Embodiment was installed in the oil pan. It is sectional drawing which shows the main-body part in 1st Embodiment, Comprising: It is a figure which also shows the 3rd position in an assembly | attachment process. It is a top view of the body in a 1st embodiment. It is a bottom view of the cover in a 1st embodiment. It is sectional drawing which shows typically the 0th position in the assembly | attachment process in 1st Embodiment. It is sectional drawing which shows typically the 1st position in the assembly | attachment process in 1st Embodiment. It is sectional drawing which shows typically the 2nd position in the assembly | attachment process in 1st Embodiment. It is a perspective view which shows the front-end | tip of the inner shaft in 2nd Embodiment. It is sectional drawing which shows the main-body part in 3rd Embodiment, Comprising: It is a figure corresponding to FIG.

Hereinafter, a plurality of embodiments will be described with reference to the drawings. In addition, the overlapping description may be abbreviate | omitted by attaching | subjecting the same code | symbol to the corresponding component in each embodiment. When only a part of the configuration is described in each embodiment, the configuration of the other embodiment described above can be applied to the other part of the configuration. In addition, not only combinations of configurations explicitly described in the description of each embodiment, but also the configurations of a plurality of embodiments can be partially combined even if they are not explicitly specified unless there is a problem with the combination. .
(First embodiment)
As shown in FIG. 1, the liquid level detection device 100 according to the first embodiment is mounted on an internal combustion engine of a vehicle and installed in an oil pan 1 as a container. The oil pan 1 is attached to the bottom surface of a cylinder block of an internal combustion engine, and stores engine oil as a liquid. The liquid level detection device 100 detects the liquid level LL of the engine oil stored in the oil pan 1.

The liquid level detection device 100 mainly includes a connector part 6, a main body part 10, and a wire 7. The connector portion 6 liquid-tightly closes the opening 1a provided on the side wall of the oil pan 1, and is a mating connector portion (not shown) for electrically connecting to an external vehicle-mounted device (for example, a combination meter). ) And can be fitted. The main body 10 is fixed to the oil pan 1 in the installed state of FIG. The main body 10 can detect the liquid level LL of the engine oil stored in the oil pan 1. The wire 7 electrically connects the connector portion 6 and the main body portion 10, and is disposed, for example, over the bracket 2. Thus, the liquid level detection device 100 can output the detection signal from the main body 10 to the outside via the wire 7 and the connector unit 6.

Hereinafter, the main body 10 of the liquid level detection device 100 will be described in detail with reference to FIGS. As shown in FIG. 2, the main body 10 of the liquid level detection device 100 includes a body 20, a cover 40, a float 50, and a reed switch 60 as a detection element.

The bodies shown in FIGS. 2 and 3 are made of, for example, polyphenylene sulfide (PPS) resin. The body 20 includes a body partition wall 22, a fitting peripheral wall 24, a fitting hole 26, a communication hole 28, a body engaging portion 30, and a flange portion 32.

The body partition wall 22 is formed in a disc shape and partitions the storage chamber 12. A plurality of protruding body stoppers 23 are provided on the body partition wall 22 on the cover 40 side. Each body stopper 23 extends along the radial direction of the body partition wall 22. The body stoppers 23 are arranged at equal intervals (for example, 90 ° intervals) in the circumferential direction of the body partition wall 22.

The fitting peripheral wall 24 is formed so as to surround the outer periphery of the disk-shaped body partition wall 22. The fitting peripheral wall 24 has a peripheral wall surface 24a on the outer periphery along a predetermined fitting direction WF. The fitting direction WF in the present embodiment is a disc-shaped thickness direction and is a direction from the cover 40 toward the body 20.

The fitting hole 26 is provided on the cover 40 side at the center of the disc-shaped body partition wall 22 on the inner peripheral side of the fitting peripheral wall 24, and is cylindrical in the fitting direction WF with respect to the body partition wall 22. It is recessed.

The communication hole 28 is provided through the fitting hole 26 and communicates with the oil pan 1 by being recessed in the fitting direction WF. That is, the body 20 is penetrated by the fitting hole 26 and the communication hole 28.

A plurality of body engaging portions 30 are formed at intervals on the outer periphery of the body partition wall 22 so as to divide the fitting peripheral wall 24. In particular, in the present embodiment, four body engaging portions 30 are formed. Each body engaging portion 30 is provided with an engaging hole 30a penetrating in the fitting direction WF. A claw-like engagement projection 30b is provided inside each engagement hole 30a. The side surface of each engagement protrusion 30b is inclined with respect to the fitting direction WF, facing the fitting direction WF and facing the fitting surface 30c substantially perpendicular to the fitting direction WF, and facing the opposite direction to the fitting direction WF. It forms a slope 30d.

The flange portion 32 is formed in a bowl shape on the outer peripheral side of the body partition wall 22 formed in a disc shape. An assembly ring 32a formed in a cylindrical shape with metal is embedded in the flange portion 32. The flange portion 32 of the body 20 can be assembled to the oil pan 1 by screwing the bracket 2 with the assembly ring 32a.

As shown in FIGS. 2 and 4, the cover 40 is formed into a bottomed cylindrical shape as a whole by using, for example, PPS resin which is the same material as the body 20. The cover 40 integrally includes a bottom wall 42, an outer cylinder 44, and an inner shaft 46, and is fitted to the body 20 by the outer cylinder 44 and the inner shaft 46.

The bottom wall 42 is disposed in a direction opposite to the mating direction WF in the cover 40 and is formed in a disc shape.

The outer cylinder 44 protrudes from the outer peripheral part of the bottom wall 42 along the fitting direction WF, and is formed in a cylindrical shape. The outer cylinder 44 is fitted into the fitting peripheral wall 24 in a press-fit state along the fitting direction WF. Further, the outer cylinder 44 has outer cylinder engaging portions 44 a provided at four locations corresponding to the body engaging portions 30 in the circumferential direction. Each outer cylinder engaging portion 44a is provided so as to be elastically deformable, and forms an engaging claw 44b. Each engagement claw 44b is further extended in the fitting direction WF from the tip of the outer cylinder 44 so that it can be inserted into each engagement hole 30a. In this way, each outer cylinder engaging portion 44a and each body engaging portion 30 are engaged.

The inner shaft 46 protrudes along the fitting direction WF from the inner peripheral portion of the bottom wall 42 on the inner peripheral side of the outer cylinder 44 and is formed in a cylindrical shape. The inner shaft 46 is fitted in the fitting hole 26 along the fitting direction WF.

Further, a plurality of cover stoppers 43 are provided on the bottom wall 42 on the body 20 side. Each cover stopper 43 extends radially from the inner shaft 46 toward the outer cylinder 44. The cover stoppers 43 are arranged at equal intervals (for example, 60 ° intervals) in the circumferential direction of the bottom wall 42.

As shown in FIG. 2, the float 50 has a foam 52 and a magnet 54, and can float on the liquid level of the engine oil. The foam 52 is formed in a cylindrical shape with a material having a specific gravity smaller than that of engine oil such as foamed phenol resin. An annular holding groove 52 a is formed on the inner peripheral side of the foam 52. The magnet 54 is a permanent magnet such as ferrite and is formed in a cylindrical shape. The magnet 54 is held in the foam 52 by being fitted in the holding groove 52 a of the foam 52. The float 50 having such a configuration is disposed between the outer cylinder 44 and the inner shaft 46 by being inserted through the inner shaft 46 of the cover 40, and follows the liquid level LL and is guided to the inner shaft 46. While being done, it reciprocates along the direction opposite to the fitting direction WF and the fitting direction WF. The float 50 is restricted from moving toward the body 20 by contact with the body stopper 23, and is restricted from moving toward the cover 40 by contact with the cover stopper 43.

The reed switch 60 is a detection element that detects the position of the float 50 that moves along the fitting direction WF. The reed switch 60 has a glass tube 62 formed in a cylindrical shape, and a pair of leads 64a-b extending from both ends of the glass tube 62. The reed switch 60 is inserted into the inner shaft 46 in a posture in which the axial direction of the glass tube 62 is aligned with the fitting direction WF, and is disposed over the fitting hole 26 and the communication hole 28. Specifically, the glass tube 62 is a hollow cylindrical glass tube, and each end portion (hereinafter referred to as a lead end portion) of each lead 64a-b is liquid-tightly accommodated. Each lead end portion is provided so as to be able to bend, and faces each other with a predetermined interval. When a magnetic field from the magnet 54 acts on each lead end, each lead end attracts each other by being magnetized to different magnetic poles. Thus, the respective lead end portions come into contact with each other, and the reed switch 60 is turned on so as to be conductive between the respective leads 64a and 64b. On the other hand, if a sufficient magnetic field from the magnet 54 does not act on each lead 64a-b, the lead ends do not contact each other, and the reed switch 60 is turned off.

Terminals

70a and 70b are formed in a strip shape from a conductive material such as brass. The

terminals

70a and 70b are held in the body 20 by being insert-molded in the body 20. One terminal 70 a is accommodated in the inner shaft 46 and extends to a position closer to the bottom wall 42 than the glass tube 62. The terminal 70a is connected to one lead 64a and supports the lead 64a. The other terminal 70b is connected to the other lead 64b in the vicinity of the fitting hole 26, and supports the lead 64b. The reed switch 60 is held with respect to the body 20 by being attached to each terminal 70a-b.

When the liquid level detection device 100 is installed in the oil pan 1 in this way, the float 50 is fitted to the reed switch 60 inserted in the inner shaft 46 when the engine oil liquid level LL is sufficiently high. It is moving in the direction WF. In this case, since the magnet 54 is close to the reed switch 60, the reed switch 60 is turned on. On the other hand, when the engine oil decreases, the float 50 moves in the direction opposite to the fitting direction WF with respect to the reed switch 60 inserted in the inner shaft 46. In this case, since the magnet 54 is separated from the reed switch 60, the reed switch 60 is turned off. That is, the liquid level detecting device 100 can detect the level LL of the engine oil stored in the oil pan 1 by detecting the position of the float 50 where the reed switch 60 moves along the fitting direction WF. It becomes possible.

Here, the assembly process of the body 20 and the cover 40 will be described as a method of manufacturing the liquid level detection device 100 according to the first embodiment with reference to FIGS.

The lead switch 60 is attached in advance to the

terminals

70a and 70b by welding and heat caulking on the body 20 before the assembly process. Further, the float 50 is inserted into the inner shaft 46 in the cover 40 before the assembly process. However, in FIGS. 5 to 7, the reed switch 60, the

terminals

70a and 70b, and the float 50 are omitted.

In the assembly process, the side of the body 20 on which the fitting peripheral wall 24 and the fitting hole 26 are formed is opposed to the side of the cover 40 on which the tip of the outer cylinder 44 and the tip of the inner shaft 46 are formed. Then, the cover 40 is assembled to the body 20 along the fitting direction WF.

Specifically, in the first embodiment, first, as shown in FIG. 5, the tip of the inner shaft 46 of the cover 40 reaches the opening of the fitting hole 26 (the position of the cover 40 is set to the initial position). P0). Here, since the outer diameter DS at the tip of the inner shaft 46 is substantially the same as the diameter DH of the fitting hole 26, the inner shaft 46 is fitted into the fitting hole 26 along the fitting direction WF. The cover 40 is guided by the fitting so as to be assembled in a direction along the fitting direction WF. In the state of the initial position P0, the engaging claws 44b of the outer cylinder engaging portion 44a are not in contact with the engaging protrusions 30b of the body engaging portion 30 and are in a free state.

Further, when the cover 40 is assembled along the fitting direction WF, as shown in FIG. 6, as the cover 40 is fitted to the body 20, the outer cylinder engaging portion 44 a is connected to the body engaging portion 30. Contact. More specifically, the engaging claw 44b of the outer cylinder engaging portion 44a comes into contact with the engaging protrusion 30b of the body engaging portion 30 at the inclined surface 30d (the position of the cover 40 is set to the first position P1). ).

Further, when the cover 40 is assembled along the fitting direction WF, the end of the outer cylinder 44 reaches the fitting peripheral wall 24 (not shown). Here, the inner diameter DP at the tip of the outer cylinder 44 is formed smaller than the outer diameter DW of the fitting peripheral wall 24 by, for example, about 0.2 to 0.5 mm. Therefore, by pressing the cover 40 in the fitting direction WF, the outer cylinder 44 is deformed to the outer peripheral side and starts fitting to the fitting peripheral wall 24 in the press-fitted state.

Further, when the cover 40 is assembled along the fitting direction WF, as shown in FIG. 7, the outer cylinder engaging portion 44 a is pressed by the body engaging portion 30 with the fitting of the cover 40 to the body 20. Elastically deforms. More specifically, the engaging claw 44b of the outer cylinder engaging portion 44a is pressed along the inclined surface 30d of the engaging protrusion 30b of the body engaging portion 30 and is elastically deformed to the inner peripheral side (this cover). The position 40 is set as the second position P2.)

Further, when the cover 40 is assembled along the fitting direction WF, as shown in FIG. 2, as the cover 40 is fitted to the body 20, the outer cylinder engaging portion 44 a is elastically restored and the body engaging portion 30. Engage with. More specifically, the engaging claw 44b of the outer cylinder engaging portion 44a gets over the engaging protrusion 30b of the body engaging portion 30 and wraps around the back of the engaging surface 30c, so that the engaging claw 44b and the engaging protrusion 30b (The position of the cover 40 is set as the third position P3). Thus, the assembly process of the body 20 and the cover 40 is completed. In the first embodiment, the tip of the inner shaft 46 stops at the boundary between the fitting hole 26 and the communication hole 28 at the third position P3.

In the liquid level detection apparatus 100 after the assembly process, the distance at which the outer cylinder 44 is fitted to the fitting peripheral wall 24 is defined as an outer cylinder fitting distance SP. In particular, in the first embodiment, the outer cylinder fitting distance SP corresponds to a distance along the fitting direction WF between the tip of the outer cylinder 44 and the end of the peripheral wall surface 24a, as shown in FIG. Further, the distance at which the inner shaft 46 is fitted to the fitting hole 26 is defined as an inner shaft fitting distance SS. Particularly in the first embodiment, the inner shaft fitting distance SS corresponds to a distance along the fitting direction WF between the tip of the inner shaft 46 and the opening of the fitting hole 26 as shown in FIG. This substantially coincides with the distance from the opening of the joint hole 26 to the boundary between the fitting hole 26 and the communication hole 28. Furthermore, the distance between the first position P1 indicated by a two-dot chain line in FIG. 2 and the third position P3 indicated by a solid line in FIG. 2 is defined as an engagement distance SE. In the present embodiment, the engagement distances SE corresponding to the body engaging portions 30 and the outer cylinder engaging portions 44a are set to be substantially the same.

At least one of the outer cylinder fitting distance SP and the inner shaft fitting distance SS is set to be larger than the engagement distance SE. More specifically, the inner shaft fitting distance SS is the largest, the engagement distance SE is the next largest, and the outer cylinder fitting distance SP is the smallest. By such setting, in the assembly process, the inner shaft 46 corresponding to the largest inner shaft fitting distance SS is first fitted into the fitting hole 26, and the outer cylinder corresponding to the outer cylinder fitting distance SP is started. Next, the fitting of the cylinder 44 to the fitting peripheral wall 24 is started, and the contact between the outer cylinder engaging portion 44a and the body engaging portion 30 corresponding to the engaging distance SE is thereafter.

The operational effects of the first embodiment described above will be described below.

According to the first embodiment, according to at least one of the outer cylinder fitting distance SP and the inner shaft fitting distance SS larger than the engagement distance SE, the cover 40 is attached to the body 20 in a predetermined fitting direction. In the case of fitting along the WF, the outer tube 44 and the fitting peripheral wall 24 are fitted and the inner shaft 46 and the fitting hole 26 before the contact between the outer tube engaging portion 44a and the body engaging portion 30. At least one of the fittings is started. As the cover 40 is fitted to the body 20, the outer cylinder engaging portion 44a contacts the body engaging portion 30 at the first position P1, and then the outer cylinder engaging portion 44a is moved to the body at the second position P2. The outer cylinder engaging part 44a is elastically restored and engaged with the body engaging part 30 at the third position P3 after being pressed and elastically deformed by the engaging part 30. According to this, after the cover 40 is guided so as to be assembled along the fitting direction WF, the outer cylinder engaging portion 44a is elastically deformed, so that the assembly can be performed smoothly. Further, since the body 20 and the cover 40 are fitted on the inner peripheral side and the outer peripheral side, respectively, the holding force of the cover 40 is increased and the vibration is restricted, so that the cover 40 can be prevented from falling off the body 20. As described above, it is possible to provide the liquid level detection device 100 that prevents the dropout.

Further, according to the first embodiment, the body 20 has the communication hole 28 that can communicate with the oil pan 1 through the fitting hole 26. When the inner shaft 46 is fitted into the fitting hole 26 that communicates with the communication hole 28, air can be released through the communication hole 28, so that the inner shaft 46 can be firmly fitted. As a result, dropout can be prevented.
(Second Embodiment)
As shown in FIG. 8, the second embodiment is a modification of the first embodiment.

The inner shaft 246 in the liquid level detection device 200 of the second embodiment projects along the fitting direction WF from the inner peripheral portion of the bottom wall 42 on the inner peripheral side of the outer cylinder 44, as in the first embodiment. It is formed in a cylindrical shape. Here, the tip of the inner shaft 246 has a window 246a that allows deformation of the tip. More specifically, as shown in FIG. 8, two U-shaped notched windows 246 a are provided at the tip of the inner shaft 246 at positions facing each other. The inner shaft 246 is fitted into the fitting hole 26 along the fitting direction WF in a press-fitted state.

In the assembly process of the body 20 and the cover 40 of the liquid level detection device 200, first, the tip of the inner shaft 246 reaches the opening of the fitting hole 26 (the position of the cover 40 is initially set). Set as position P0). Here, the outer diameter DS at the tip of the inner shaft 246 is formed to be larger than the diameter DH of the fitting hole 26 by, for example, about 0.2 to 0.5 mm. Therefore, by pressing the cover 40 in the fitting direction WF, the distal end of the inner shaft 246 that is allowed to be deformed by the window 246a is deformed to the inner peripheral side, and the fitting to the fitting peripheral wall 24 in the press-fitted state is performed. Start. As in the first embodiment, the cover 40 is guided by this fitting so as to be assembled in a direction along the fitting direction WF. In the state of the initial position, the engaging claw 44b of the outer cylinder engaging portion 44a is not in contact with the engaging protrusion 30b of the body engaging portion 30, and is in a free state.

Also in the second embodiment described above, at least one of the outer cylinder fitting distance SP and the inner shaft fitting distance SS is set to be larger than the engagement distance SE. Therefore, it is possible to achieve the operational effects according to the first embodiment.

According to the second embodiment, the tip of the inner shaft 246 fitted into the fitting hole 26 in the press-fitted state has the window 246a that allows deformation of the tip. According to this, even if it is the front-end | tip of the inner shaft 246 which is hard to deform | transform because the outer diameter DS is smaller than the outer cylinder 44, since it becomes easy to deform | transform, it can fit in a press-fit state easily. As a result, dropout can be prevented.
(Third embodiment)
As shown in FIG. 9, the third embodiment is a modification of the first embodiment.

As shown in FIG. 9, the fitting peripheral wall 324 in the liquid level detection device 300 of the third embodiment protrudes in the direction opposite to the fitting direction WF with respect to the body partition wall 22. The fitting peripheral wall 324 has a peripheral wall surface 324a on the outer periphery along the fitting direction WF including the protruding range.

The outer cylinder fitting distance SP and the inner shaft fitting distance SS are set to be larger than the engagement distance SE. However, in the third embodiment, due to the protrusion of the fitting peripheral wall 324, the outer cylinder fitting distance SP is the largest, the inner shaft fitting distance SS is the second largest, and the engagement distance SE is the smallest.

In the assembly process of the body 20 and the cover 40 of the liquid level detection device 300, first, the tip of the outer cylinder 44 reaches the fitting peripheral wall 324 (the position of the cover 40 is set to the initial position P0). And set). Here, the inner diameter DP at the tip of the outer cylinder 44 is formed smaller than the outer diameter DW of the fitting peripheral wall 324 by, for example, about 0.2 to 0.5 mm. Therefore, by pressing the cover 40 in the fitting direction WF, the outer cylinder 44 is deformed to the outer peripheral side and starts fitting to the fitting peripheral wall 324 in the press-fitted state. And the cover 40 is guided by this fitting so that it may be assembled | attached in the direction along the fitting direction WF. In the state of the initial position P0, the engaging claws 44b of the outer cylinder engaging portion 44a are not in contact with the engaging protrusions 30b of the body engaging portion 30 and are in a free state.

Further, when the cover 40 is assembled along the fitting direction WF, the tip of the inner shaft 46 of the cover 40 reaches the opening of the fitting hole 26, and the inner shaft 46 is fitted in the fitting hole 26 as in the first embodiment. Fitted.

Also in the third embodiment described above, at least one of the outer cylinder fitting distance SP and the inner shaft fitting distance SS is set to be larger than the engagement distance SE. Therefore, it is possible to achieve the operational effects according to the first embodiment.

Further, according to the third embodiment, the fitting peripheral wall 324 protrudes in the direction opposite to the fitting direction WF. According to this, since the outer cylinder fitting distance SP can be set as long as possible, it is easy to make the outer cylinder fitting distance SP larger than the engagement distance SE. As a result, dropout can be prevented.

Although a plurality of embodiments have been described above, the present disclosure is not construed as being limited to those embodiments, and can be applied to various embodiments and combinations without departing from the scope of the present disclosure. Can do.

Specifically, as a first modification regarding the first to third embodiments, as long as the detection element detects the position of the float 50, an element other than the reed switch 60 may be used. As an example of this, the Hall element may be used as a detection element after some processing for liquid resistance is performed.

As a second modification related to the first to third embodiments, as long as one of the outer cylinder fitting distance SP and the inner shaft fitting distance SS satisfies the relationship that it is larger than the engagement distance SE, the magnitude of these distances The order of may be other orders. As this example, the inner shaft fitting distance SS is the largest, the outer cylinder fitting distance SP is the next largest, the engagement distance SE may be set the smallest, or the outer cylinder fitting distance SP is the largest. Then, the engagement distance SE may be set to be the largest, and the inner shaft fitting distance SS may be set to be the smallest.

As a third modification related to the first to third embodiments, the body 20 may not have the communication hole 28 that can communicate with the oil pan 1.

As a fourth modification related to the first to third embodiments, the outer diameter DS of the tip of the inner shaft 46 is formed larger than the diameter DH of the fitting hole 26, so that the inner shaft 46 is press-fit and the fitting hole 26 is And the inner diameter DP at the tip of the outer cylinder 44 is substantially the same as the outer diameter DW of the fitting peripheral wall 24 so that the outer cylinder 44 is completely fitted to the fitting peripheral wall 24. May be.

As a fifth modified example related to the first to third embodiments, the fitting peripheral wall 24 may have a peripheral wall surface 24a on the inner periphery. Further, the outer cylinder 44 may be deformed to the inner peripheral side and fitted with the fitting peripheral wall 24 in a press-fitted state.

As a sixth modified example related to the first to third embodiments, the application target of the present disclosure is not limited to the detection of the engine oil liquid level LL. The present disclosure can be applied to a liquid level detection device in a container for other liquids mounted on the vehicle, such as brake fluid, engine coolant, and fuel. Furthermore, the present disclosure is applicable not only to vehicles but also to liquid level detection devices in containers provided in various consumer devices and various transport machines.

Although the present disclosure has been described based on the embodiments, it is understood that the present disclosure is not limited to the embodiments and structures. The present disclosure includes various modifications and modifications within the equivalent range. In addition, various combinations and forms, as well as other combinations and forms including only one element, more or less, are within the scope and spirit of the present disclosure.

Claims

In the liquid level detection device for detecting the liquid level (LL) of the liquid stored in the container (1),
A fitting peripheral wall (24, 324) that can be assembled to the container (1) and forms a peripheral wall surface (24a, 324a) along a predetermined fitting direction (WF), and the fitting peripheral wall (24 , 324) and a body (20) having a fitting hole (26) provided on the inner peripheral side,
A cover (40) fitted to the body (20), the outer cylinder (44) fitted to the fitting peripheral wall (24, 324) along the fitting direction (WF); A cover (40) integrally forming an inner shaft (46, 246) fitted in the fitting hole (26) along the fitting direction (WF) on the inner peripheral side of the outer cylinder (44). When,
A float (50) disposed between the outer cylinder (44) and the inner shaft (46, 246) and floating in the liquid;
A detection element (60) that is inserted into the inner shaft (46, 246) and detects the position of the float (50),
The outer cylinder (44) has an outer cylinder engaging part (44a) provided so as to be elastically deformable,
The body (20) has a body engaging portion (30) provided to be engageable with the outer cylinder engaging portion (44a),
A first position (P1) where the outer cylinder engaging portion (44a) contacts the body engaging portion (30) as the cover (40) is fitted to the body (20), and the outer cylinder A second position (P2) where the engaging portion (44a) is pressed and elastically deformed by being pressed by the body engaging portion (30), and the outer cylinder engaging portion (44a) is elastically restored and the body engaging portion ( 30) and the third position (P3) to be engaged are set,
The distance between the outer cylinder (44) and the fitting peripheral wall (24, 324) is defined as the outer cylinder fitting distance (SP), and the inner shaft (46, 246) is the fitting hole ( 26) is defined as an inner shaft fitting distance (SS), and a distance between the first position (P1) and the third position (P3) is defined as an engagement distance (SE). ,
At least one of the outer cylinder fitting distance (SP) and the inner shaft fitting distance (SS) is larger than the engagement distance (SE).
The liquid level detection device according to claim 1, wherein the body (20) has a communication hole (28) capable of communicating with the container (1) through the fitting hole (26).
The tip of the inner shaft (246) fitted into the fitting hole (26) in the press-fitted state has a window (246a) that allows deformation of the tip. 2. The liquid level detection apparatus according to 2.
The fitting peripheral wall (324) protrudes in a direction opposite to the fitting direction (WF),
4. The liquid level detection device according to claim 1, wherein the outer cylinder fitting distance (SP) is larger than the engagement distance (SE). 5.