JP3028091B2 - Velocity detection device for eddy current instruments - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting a speed using a reed switch, and more particularly to a speed in an eddy current type instrument in which a mounting member to which a reed switch is mounted is fixed to an instrument frame side. The present invention relates to a detection device.

[0002]

2. Description of the Related Art An example of this kind of speed detecting device is disclosed in Japanese Utility Model Publication No. Sho 55-17176. The outline of this device is to form a hole in a wall of a housing for accommodating an instrument mechanism and to fix a reed switch to the hole. The electrical insulation member is inserted from the outside of the housing, and a flange formed around the outside of the electrical insulation member is brought into contact with the peripheral surface of the hole, so that the reed switch is arranged at a fixed position on the side surface of the magnet. It was done.

[0003]

However, in the above-mentioned conventional example, the instrument mechanism is assembled to the housing, and then the electrical insulating member to which the reed switch is fixed is attached to the housing. The distance between the magnet and the reed switch is not constant, so the opening and closing ratio of the reed switch when the magnet rotates may change. To correct this, for example, remove the instrument mechanism from the housing. The work was not easy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a speed detecting apparatus for an eddy current type instrument which is excellent in quality and has good workability in assembling the instrument.

[0005]

According to the present invention, to solve the above-mentioned problems, a plate is erected on an open end of an instrument frame having a side wall and a bottom wall, and a rotating shaft is provided on the bottom wall of the instrument frame via a bearing member. A magnet is fixed to the upper end of the rotating shaft, and a guide plate that rotates by an eddy current action generated by the rotation of the magnet is disposed with a small gap between the magnet and the guide plate. A pointer shaft is fixed, and a pointer for indicating a display portion of a display plate attached and fixed in front of the plate is fixed to the upper end of the pointer shaft. An electrically insulating mounting member to which the switch is mounted is disposed in a direction orthogonal to the side wall of the instrument frame, and a mounting portion projects at both ends of the mounting member, and the mounting portion is provided on both side walls of the instrument frame. Solid
It is specified .

According to the present invention, the reed switch is disposed so as to face the lower surface of the magnet.

Further, according to the present invention, the mounting portion is formed of a conductive member electrically connected to a lead of a reed switch, and at least one of the mounting portions has an acute angle with the mounting member and is elastically deformable. It is formed in.

In the present invention, the mounting portion is formed integrally with the mounting member, and at least one of the mounting portions has an acute angle with the mounting member and is formed so as to be elastically deformable.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A plate 9 is erected at the open end of an instrument frame 3 having a side wall 1 and a bottom wall 2, and the instrument frame 3
A rotating shaft 5 is rotatably supported on the bottom wall 2 via a bearing member 4, a magnet 6 is fixed to an upper end of the rotating shaft 5, and an induction plate 13 that rotates by an eddy current action generated by the rotation of the magnet 6. The indicator shaft 12 is fixed to the center of the guide plate 13, and a display portion of a display plate 17 fixed to the front of the plate 9 is provided at the upper end of the indicator shaft 12. A pointer 14 for indicating is fixed, and a reed switch 18 is disposed so as to face the magnet 6, and an electrically insulating mounting member 19 to which the reed switch 18 is mounted is attached in a direction orthogonal to the side wall 1 of the instrument frame 3. The mounting member 1
At the opposite ends of the instrument 9, mounting portions 21 are projected, and the mounting portions 21 are fixed to both side walls of the instrument frame 3.
The position of the magnet 6 and the reed switch 18 can be kept constant by attaching the instrument frame 3 to the instrument frame 3 itself and fixing it to both side walls, and the distance between the magnet 6 and the reed switch 18 is always kept constant.
The speed can be detected in a stable quality without largely changing the opening / closing ratio of the reed switch 18.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described based on a first embodiment shown in FIGS. A rotating shaft 5 is supported by a bottom wall 2 of an instrument frame 3 having a side wall 1 and a bottom wall 2 via a bearing member 4,
A magnet 6 is fixed to the upper end of the rotating shaft 5. A magnetic guide plate 7 is disposed on the outer periphery of the magnet 6, and the magnetic guide plate 7 is fixed to an inner peripheral wall of a cup-shaped magnetic plate holder 8 made of a non-magnetic material. Like the magnet 6, it is fixed to the upper end of the rotating shaft 5. A plate 9 is provided at the open end of the instrument frame 3. An upper bearing 10 is formed at the center of the plate 9, and a lower bearing 11 is formed at the center of the upper end of the rotating shaft 5.
Is supported. A magnet 6 is provided at the lower end of the pointer shaft 12.
A guide plate 13 is fixedly arranged with a small gap between the guide plate 7 and the magnetic guide plate 7, and a pointer 14 is press-fitted and fixed to the upper end, and an inner end of a mustache spring 15 is located below the center of the pointer shaft 12. It is fixed, and its outer end is fixed to a beard holder 16 provided on the plate 9. Reference numeral 17 denotes a display plate mounted and fixed on the plate 9 with screws or the like.

A reed switch 18 is provided between the magnet 6 and the bottom wall 2 of the instrument frame 3 so as to face the lower surface of the magnet 6.
Is arranged. The reed switch 18 is disposed substantially at the center of an electrically insulating mounting member 19 formed to have substantially the same length as the length between the side walls 1 of the instrument frame 3, and the reed switch 18 of the reed switch 18 bent at a right angle. Is penetrated by the mounting member 19.

At both ends of the mounting member 19, mounting portions 21 made of a conductive member are provided. The mounting portion 21 is formed in an L-shape, and one of the mounting portions 21 is orthogonal to the mounting member 19 from the end face of the mounting member 19. The lead 20 extends along the mounting member 19, and the other lead 20 extends through the mounting member 19 along the mounting member 19.
And is held by a guide 22 provided on the mounting member 19. Note that one of the mounting portions 2
1 is formed to be bent to less than 90 degrees and to be elastically deformable. Then, the reed switch 18 and the mounting portion 2
Although not shown, the mounting member 19 to which the mounting member 1 is attached is positioned with the instrument frame 3, and the mounting portion 21 is fixed to the side wall 1 of the instrument frame 3 by screws 23.

The operation of the speed detecting device in the eddy current instrument constructed as described above will be described. The rotation from the vehicle is transmitted to the rotating shaft 5 via a flexible cable (not shown), and the magnet 6 rotates together with the rotating shaft 5. The guide plate 13 is rotated by an eddy current effect generated by the rotation, the guide plate 12 is rotated in balance with the elastic force of the mustache spring 15, and the rotation angle of the pointer 14 press-fitted and fixed to the pointer shaft 12 is displayed. It is compared with a display unit provided on the plate 17 and measured and displayed.

On the other hand, the reed switch 18 disposed so as to face the lower surface of the magnet 6 opens and closes by the rotation of the magnet 6, and the mounting portion 2 connected to the reed switch 18 by soldering.
By connecting to a lamp, not shown, via 1 for example, when the running speed of the vehicle reaches a certain speed, this can be detected and the lamp can be turned on to give an alarm.

In this embodiment, as described above, the electrically insulating mounting member 19 to which the reed switch 18 is mounted is attached to the mounting portion 2.
By fixing the magnet 6 to the instrument frame 3 that supports the magnet 6 and fixing the magnet 6 to the side walls, the magnet 6 and the reed switch 18 can be stably set. Distance is always kept constant, and the speed can be stably detected in terms of quality without greatly changing the opening / closing ratio of the reed switch 18. Therefore, as in the conventional example, there is no need to remove the instrument mechanism after assembling the instrument mechanism to the housing, and the instrument assembly workability is good.

Further, since the reed switch 18 is provided so as to face the lower surface of the magnet 6, the gauge can be made more compact as compared with the conventional example in which the reed switch is provided so as to face the side surface of the magnet.

Further, since one of the mounting portions 21 is bent to less than 90 degrees and is formed so as to be elastically deformable, when the mounting portion 21 is inserted along the side wall 1 of the instrument frame 3, the mounting portion 21 faces outward. Since the mounting portion 21 is temporarily fixed to the side wall 1 of the instrument frame 3 by the force of being inserted while being bent, the mounting portion 21 is
When tightening and fixing with 3, the mounting member 19 to which the reed switch 18 is mounted does not come off the instrument frame 3 and the workability is good. Also, by providing the mounting portion 21 as a conductive member, for example, if a part of the mounting portion is extended and screwed to an external circuit from outside the instrument housing (not shown), the electrical connection with the reed switch can be easily performed. Becomes

FIG. 4 shows a mounting member 19 to which a reed switch 18 according to a second embodiment of the present invention is mounted. The mounting portion 21 in the present embodiment is formed integrally with the electrically insulating mounting member 19, and the mounting portion 21 has an angle of less than 90 degrees with the mounting member 19 as in the first embodiment, and has an elasticity. It is provided so as to be deformable. The tip of the lead 20 of the reed switch 18 bent at a right angle is attached to the mounting member 19.
And is soldered to the conducting member 24. As described above, the current-carrying member 24 is provided with an extension 25 for facilitating electrical connection to an external circuit, and is held on the mounting member 19 by the guide 22 as in the first embodiment. The conducting member 24 does not need to be provided. For example, the tip of the lead 20 may be soldered to an electric cord, and the electric cord may be electrically connected to an external circuit.

With this configuration, the mounting member 1
When the mounting portion 21 integrally formed with the instrument 9 is inserted along the side wall 1 of the instrument frame 3, the mounting portion 21 is inserted while flexing outward, and is attached by a force that attempts to return to the original position.
Is temporarily fixed to the side wall 1 of the instrument frame 3, so that the workability in tightening and fixing the mounting portion 21 to the side wall 1 with the screw 23 is good as in the first embodiment.

[0020]

According to the present invention, an electrically insulating mounting member to which a reed switch is mounted is disposed in a direction perpendicular to the side wall of the instrument frame, and mounting portions project from both ends of the mounting member. Fix the mounting parts on both sides of the instrument frame.
As a result, the magnet can be fixed to the instrument frame itself that supports the magnet and fixed to both side walls, enabling stable position setting.The distance between the magnet and the reed switch is always kept constant, and the open / close ratio of the reed switch is kept constant. Speed detection stable in quality can be performed without a large change.

Further, according to the present invention, the instrument can be made compact by disposing the reed switch facing the lower surface of the magnet.

Further, according to the present invention, the mounting portion is formed of a conductive member electrically connected to the lead of the reed switch, and at least one of the mounting portions is formed at an acute angle with the mounting member so as to be elastically deformable. By doing so, workability when fastening the fixing portion to the side wall with screws is good. Also, electrical connection between the external circuit and the reed switch is easy.

Further, according to the present invention, the mounting portion is formed integrally with the mounting member, and at least one of the mounting portions is formed at an acute angle with the mounting member so as to be elastically deformable. Good workability when tightening and fixing with screws.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an eddy current type instrument provided with a reed switch according to a first embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of the eddy current meter provided with the reed switch showing the embodiment.

FIG. 3 is a mounting member to which the reed switch according to the embodiment is mounted.

FIG. 4 shows a mounting member to which a reed switch according to a second embodiment of the present invention is mounted.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Side wall 2 Bottom wall 3 Instrument frame 4 Bearing member 5 Rotating shaft 6 Magnet 9 Plate 12 Pointer shaft 13 Guide plate 14 Pointer 17 Display plate 18 Reed switch 19 Mounting member 20 Lead 21 Mounting part

Claims (4)

(57) [Claims] 1. A plate is provided on an open end of an instrument frame having a side wall and a bottom wall, a rotating shaft is supported on a bottom wall of the instrument frame via a bearing member, and a magnet is fixed to an upper end of the rotating shaft. Then, an induction plate that is rotated by an eddy current effect generated by the rotation of the magnet is arranged through the magnet and a small gap,
A pointer shaft is fixed to the center of the guide plate, and a pointer for indicating a display portion of a display plate fixedly mounted in front of the plate is fixed to an upper end of the pointer shaft, and a reed switch is arranged to face the magnet. At the same time, an electrically insulating mounting member to which the reed switch is mounted is disposed in a direction orthogonal to the side wall of the instrument frame. A velocity detecting device for an eddy current type instrument fixed to both side walls of an instrument frame. 2. The speed detecting device according to claim 1, wherein the reed switch is disposed so as to face a lower surface of the magnet. 3. The mounting portion is made of a conductive member electrically connected to a lead of a reed switch, and at least one of the mounting portions has an acute angle with the mounting member and is formed to be elastically deformable. 2. The method according to claim 1, wherein
Or a speed detecting device in the eddy current meter according to claim 2. 4. The mounting part according to claim 1, wherein the mounting part is formed integrally with the mounting member, and at least one of the mounting parts has an acute angle with the mounting member and is formed so as to be elastically deformable. 3. A speed detecting device in an eddy current instrument according to claim 1.