JPH0725697Y2 - Lid mounting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a device for attaching a lid, in particular, a storage case that stores a circuit board and a lid that covers an opening of the storage case with locking claws and locks. The present invention relates to a lid attachment device that is fixed by engagement with a receiving portion.

[Prior Art] A case in which this type of lid attachment device is applied to, for example, a rotation detection device installed in an automobile will be described as an example.

Various types of rotation detecting devices have been proposed. For example, as disclosed in Japanese Utility Model Publication No. 59-142764, a magnet that rotates in response to a vehicle speed is supported in a cylindrical case made of a metal material. In addition, a groove for positioning the circuit board is provided in a board storage chamber formed on the side of the magnet, and a magnetic sensor is mounted on the circuit board through the side peripheral surface of the magnet and a small clearance. It is known that the rotation of the magnet is detected to output an electric signal proportional to the traveling speed of the vehicle, thereby detecting the vehicle speed. The tubular case is attached and fixed to a vehicle transmission or the like, and is configured to transmit the rotation of the transmission to the magnet through a connecting member to rotate the magnet.

By the way, such a vehicle speed detection device is not only used in a vibrating environment, but also because it is installed in the vicinity of the engine, the temperature changes so that the ambient temperature fluctuates in the range of -30 ° C to 125 ° C. Used in the environment. Therefore, in order to withstand such an environment, the vehicle speed detection device is molded in a cylindrical case after the magnetic sensor and the circuit board are housed in a cylindrical case, as disclosed in Japanese Utility Model Laid-Open No. 61-187460. Not only does it absorb the vibration applied to the magnetic sensor by filling the agent, but it also protects the magnetic sensor and electronic components from the humidity that rises due to temperature changes, and stresses the soldered part due to expansion or contraction of the board and electronic components. Has been applied to alleviate.

However, in this case, when filling the molding agent in the case, it is necessary to consider that the molding agent does not adhere to other parts, so not only the workability is low, but also the structure inside the case tends to be complicated. Moreover, a large amount of molding agent is required, which is also disadvantageous in terms of manufacturing cost.

In consideration of such a problem, after storing the magnetic sensor and the circuit board in a box-shaped storage case having a substrate storage chamber,
By filling the storage case with a molding agent, the magnetic sensor and the circuit board are unitized in a stable state, and the above-mentioned effects can be obtained with the minimum necessary molding agent. A rotation detection device having a configuration in which the unitized magnetic sensor and the circuit board can be easily arranged in the cylindrical case by inserting the unit into the cylindrical case is conceivable.

In this case, it is necessary to provide a lid for covering the opening for inserting the circuit board in the storage case, and various means for fixing the lid and the storage case can be considered from the past. As one-touch fixing means, for example, as shown in FIG. 5, a lid 1 is provided with a locking claw 2, a storage case 3 is provided with a locking receiving portion 4, and the locking claw 2 and the locking receiving portion 4 are provided.
It is known that the lid 1 and the storage case 3 are fixed by engaging with each other.

[Problems to be Solved by the Invention] When fixing the lid 1 and the storage case 3 by the engagement of the locking claw 2 and the locking receiving portion 4, the length 1 of the locking claw 2 and the storage It is desirable to form each component so that the length l ′ from the upper end of the case 3 to the lock receiving portion 4 is equal to each other. However, this requires high accuracy, and the above-mentioned problem may occur due to a molding error of each component. The length relationship between the stopper 4 and the locking claw 2 is l
In the case of> l ′, the locking claw 2 and the locking claw 2 are not engaged with each other and the lid 1 and the storage case 3 cannot be fixed. A clearance a is set between the clearance and.

However, in the above-mentioned conventional example, since the tubular case is attached and fixed to the transmission of the vehicle, the lid 1 is loosened due to the vibration from the transmission due to the clearance a, and in the worst case, it is locked. Nail 2
There is a problem that the lid 1 is disengaged from the lock receiving portion 4 and the lid 1 comes off, and the rattling of the lid 1 inevitably causes the rattling of the circuit board 5 housed in the storage case 3. However, there is a problem in that the magnetic sensor mounted on the circuit board 5 and the magnet are displaced from each other and the detection accuracy of the magnetic sensor is deteriorated.

Therefore, the present invention firmly mounts the lid and the storage case to prevent the lid from falling off due to vibration and the like, and suppresses the fluctuation of the circuit board housed in the storage case to mount it on the circuit board and the circuit board. It is an object of the present invention to provide a lid attachment device capable of positioning and fixing attachment components.

[Operation] With the above configuration, when the lid body is mounted on the storage case, the circuit board housed in the storage case or the mounting component integrally mounted and fixed on the circuit board is pressed by the elastic piece provided on the back surface of the lid body. , The circuit board or the mounting component is pressed against a receiving portion formed on the inner wall surface of the storage case, the circuit substrate or the mounting component is positioned by the receiving portion, and the receiving portion of the storage case and the elastic piece of the lid body The circuit board or the attachment parts are held in a fixed state between them, and fluctuations of the circuit board or the attachment parts are prevented. Further, the lid body is urged in a direction in which the locking claw and the locking receiving portion are brought into pressure contact with each other by a reaction force generated by pressing the circuit board or the mounting component, whereby the locking claw and the locking receiving portion are formed. The clearance between them is absorbed, and the engagement claw and the engagement receiving portion are engaged with each other in a state where they are always in close contact with each other, and the backlash of the lid is suppressed.

[Embodiment] An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIGS. 1 and 2 show an embodiment of the present invention, in which reference numeral 11 denotes a metal cylindrical case main body having an open upper part for fixing to the transmission side.
A rotary shaft 13 is rotatably supported inside via a bearing 12, and a hollow portion 14 into which a connecting member (not shown) for transmitting the rotation of the transmission is inserted is formed at the lower end side of the rotary shaft 13 and at the upper end thereof. A plurality of magnets 15 each having N and S poles alternately magnetized are fixed. 16 is the case body
For example, a storage case made of synthetic resin such as polyoxymethylene is fixed in the inside with a screw 17. The storage case 16 is formed in a box shape with a bottom having an opening 16A at the top, and an inner surface facing wall. The bottom wall is provided with a pair of groove-shaped engaging portions 19 as receiving portions for inserting and guiding both side edge portions of the circuit board 18 inserted and arranged in the case 16. Further, the circuit board 18 is mounted with a magnetic sensor 20 which is a mounting part integrally fixed to the circuit board 18 through a small clearance with the side peripheral surface of the magnet 15, and the magnetic sensor 20 A magnetic shield member 21 which is a mounting component made of a metal material such as brass for protecting the magnetic sensor 20 from the influence of an external magnetic field is provided in the periphery, and the magnetic shield member 21 is a tip portion of the magnetic sensor 20. To expose the mounting leg 21A into the notch groove 22 formed in the circuit board 18 and fold it back to the back side of the circuit board 18, and the bent portion of the back side of the circuit sensor 18 to prevent noise from entering the magnetic sensor 20. Circuit board by soldering to the ground electrode of the conductive pattern (not shown)
It is fixed integrally with 18. Further, a storage chamber 23 in which the magnetic sensor 20 is disposed as a receiving portion of the magnetic sensor 20 is formed in the storage case 16 so as to project from a part of a side wall to the magnet 15 side, and the left and right side wall outer surfaces of the sensor storage chamber 23 and A lock receiving portion (24) is provided at a proper position on the outer surface of the outer wall of the storage case (16).
25 is a lid made of the same material as the storage case 16,
The lid 25 has a locking claw at a position corresponding to the locking receiving portion 24.
26 is provided vertically, and an elastic piece 27 for pressing the upper surface of the magnetic shield member 21 is integrally formed.
A protrusion 28 is provided at the lower end of 27.

The magnetic sensor 20 and the circuit board 18 are molded with a molding agent 29 with which the housing case 16 is filled. In the figure, 30 is a wiring cord connected to the circuit board 18, 31 is a cover lid of the case body 11, and the wiring cord 30 has a grommet 33 integrally provided with a packing 32.
Is provided with the wiring cord through the grommet 33
30 is inserted from the insertion opening 34 provided at the upper end of the case body 11, and the cover lid 31 is screwed through the packing 32.
It is fixed to the case body 11 by 35.

According to the present invention configured as described above, after the molding agent 29 is filled, the locking claw 26 of the lid 25 is attached to the locking receiving portion 24 provided in the storage case 16, and the lid 25 is stored in the storage case. The magnetic shield member 21, which is fixed to 16, and integrally attached to and fixed to the circuit board 18 by the elastic piece 27 integrally formed with the lid 25, is pressed to push the protrusion 28 provided on the elastic piece 27. The magnetic shield member
The circuit board 18 is pressed against the bottom of the storage case 16 via the magnetic shield member 21 by abutting against the 21 in a point contact state, and the lid 25 is moved upward by the reaction force of the elastic piece 27. And thus the lock receiving portion
The 24 and the locking claw 26 can be reliably abutted against each other, the engagement between them is kept good, and the lid 25 is prevented from coming off.

Therefore, according to the present invention, the lid 25 and the storage case 16 can be easily and quickly carried out by engaging the locking claw 26 and the locking receiving portion 27,
The assembly work is improved, and furthermore, the elastic claw 26 provided on the lid body 25 abuts the locking claw 26 and the locking receiving portion 27 to suppress the rattling of the lid body 25 and stabilizes the lid body 25. The magnetic shield member 21 can be assembled and fixed by pressing the magnetic shield member 21 with the elastic piece 27.
21 is pressed against the storage chamber 23 of the storage case 16, and the circuit board 18 for integrally mounting and fixing the magnetic shield member 21 is pressed against the bottom of the engaging portion 19 formed in the storage case 16, and the circuit board 18 Also, the backlash of the magnetic sensor 20 mounted on the circuit board 18 can be suppressed at the same time.
It is also possible to stably hold the magnetic sensor 20 and the magnet 15, which are mounted in the above, in a state where they are surely aligned with each other.

The present invention is not limited to the above embodiment,
Various modifications are possible within the scope of the present invention,
For example, the shape or the number of elastic pieces provided on the lid may be appropriately set. Further, in the above-mentioned embodiment, the elastic piece provided on the lid is shown to be abutted against the magnetic shield member to be mounted on the circuit board, but not limited to this, it may be abutted to various mounting parts to be mounted on the circuit board. Alternatively, a dedicated component for receiving the elastic piece may be assembled on the circuit board. Further, the elastic piece is not limited to a mounting part to be mounted on the circuit board, and for example, as shown in FIG. 3, a substantially L-shaped elastic piece 27A provided on the lid 25 in the notch groove portion 36 provided on the upper end portion of the circuit board 18. The circuit board 18 may be directly pressed by the elastic pieces 27A to suppress the rattling of the lid 25.

Further, in the above-described embodiment, the lid is provided with the locking claw, and the storage case is provided with the lock receiving portion. However, as shown in FIG. 4, a cutout groove 37 is formed in the peripheral wall of the storage case 16. By this, elastically deformable locking claws 26A are provided, and storage case 16 is provided with a notch groove-shaped locking receiving part 24A at a position corresponding to the locking claws 26A. Lid by engaging with 24A
25 may be fixed to the storage case 16.

Further, the structure of the rotation detecting device can be applied to various types, and the present invention is not limited to the rotation detecting device and can be widely used for vehicle instruments or various home appliances.

[Advantages of the Invention] The present invention has a box-shaped storage case having an opening at least in part, a circuit board disposed in the storage case through the opening, and integrally attached to the circuit board. An attachment part for fixing and a lid that covers the opening are provided, and a locking claw is provided on either one of the storage case and the lid,
In the lid mounting device for fixing the lid to the storage case by engaging the locking claw and the lock receiving portion on the other side, an inner wall surface of the storage case is provided. While forming a receiving portion that abuts the circuit board or the mounting component, the circuit board or the mounting component is elastically pressed against the back surface of the lid body to mount the circuit board or the mounting component on the receiving portion. By providing an elastic piece that press-contacts and urges the lid body by a reaction force caused by pressing on the circuit board or the mounting component to press the locking claw and the locking receiving portion into contact with each other, The storage case is firmly fixed, the lid is prevented from falling off due to vibration from the vehicle side, and the circuit board stored in the storage case is restrained from varying and the mounting parts to be mounted on the circuit board are mounted. It is possible to provide a lid mounting device that can be positioned and fixed. That.

[Brief description of drawings]

1 and 2 show an embodiment of the present invention, FIG. 1 is a sectional view, FIG. 2 is an exploded perspective view, and FIGS. 3 and 4 show another embodiment of the present invention. FIG. 3 is a sectional view, FIG. 4 is an exploded perspective view of an essential part, and FIG. 5 is a sectional view of an essential part showing a conventional example. 16 ... Storage case, 16A ... Opening portion 18 ... Circuit board, 19 ... Engaging portion (receiving portion) 20 ... Magnetic sensor (mounting component), 21 ... Magnetic shield member (mounting component) 23 ... Storage chamber (receiving portion), 24, 24A: Lock receiving part 26, 26A: Locking claw, 27, 27A: Elastic piece

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Atsushi Kondo Atsushi Kondo 2-32 Higashi Zao, Nagaoka City, Niigata Japan Inside Seiki Co., Ltd. (56) References

Claims (1)

[Scope of utility model registration request] 1. A box-shaped storage case having an opening at least in a part thereof, a circuit board disposed in the storage case through the opening, and a mounting component integrally mounted and fixed to the circuit board. And a lid that covers the opening, and a locking claw is provided on one side of the storage case and the lid, and a locking receiving portion is provided on the other side. In a lid mounting device that engages with a stopper to fix the lid to the storage case, a receiving portion that contacts the circuit board or the mounting component is formed on an inner wall surface of the storage case, The circuit board or the mounting component is elastically pressed against the back surface of the lid to press the circuit board or the mounting component into pressure contact with the receiving portion, and the reaction force due to the pressing on the circuit board or the mounting component. Urging the lid body to press the locking claw and the locking receiving portion into pressure contact with each other. Mounting device of the lid, characterized in that a sex piece.