JP3211922B2 - Method for manufacturing a movement for a cross-coil instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates relates to the movement and its manufacturing method for a cross-coil type instrument suitable like instrument vehicle, cross coil type instrument Mubumen bets pointer is fixed in particular by press-fitting the tip of the rotary shaft And a method for producing the same.

[0002]

2. Description of the Related Art FIG. 5 shows an example of the structure of a movement 10 of a cross-coil type instrument generally used for a vehicle indicating instrument. An upper bobbin 21 and a lower bobbin 22 formed of a synthetic resin are abutted from above and below to form a coil bobbin 20, a magnet rotor 12 is rotatably housed in the bobbin 20, and a pair of orthogonally disposed coils bobbin 20 on the outer periphery. A cross coil 11 composed of a coil is wound.

The lower end 42 of the rotating shaft 40 of the magnet rotor 12 is supported by a thrust bearing 32 provided in the lower bobbin 22, and the upper end 41 of the rotating shaft 40 is
The pointer 13 is press-fitted from the direction of the arrow as shown in FIG.

In the above configuration, by passing a current that varies according to the measured amount to each coil of the cross coil 11, the magnet rotor 12 rotates in the direction of the composite magnetic field of the magnetic field generated by the cross coil 11, and The measurement amount is displayed by the pointer 13 rotating with the rotor 12 indicating a scale on a dial (not shown).

A beard ball 4 is provided below the pointer 13 of the rotating shaft 40.
The inner end of the hairspring 43 is fixed by 3a, and the outer end thereof is fixed to the upper bobbin 21. This hairspring 43
Accordingly, when the ignition switch is turned off and the signal current input to the cross coil is reduced to zero, the elasticity of the hairspring 43 returns the pointer 13 to the zero point on the scale, thereby causing the pointer 13 to be in an indeterminate position. Is prevented.

The gap between the coil bobbin 20 and the magnet rotor 12 is filled with a brake fluid 23 such as silicone oil, and the use of unnecessary swing of the magnet rotor 12 suppresses hand deflection.

The thrust bearing 32 for supporting the lower end 42 of the rotating shaft 40 comprises a bearing recess 32 a formed in the lower bobbin 22 and a steel ball 33 press-fitted therein. The thrust load applied to the rotating shaft 40 is received in contact therewith. Bearing recess 32a
Pressing of the steel ball 33 into the inside is performed with a relatively small force so that the steel ball 33 is held to the extent that it does not fall out of the bearing recess 32a during the assembly operation.

[0008] The assembling in the manufacture of the cross-coil instrument movement having the above configuration is performed in the following procedure. The magnet rotor 12 has bearings 31 above and below its rotating shaft 40.
And the thrust bearing 32, the coil bobbin 20
The upper bobbin 21 and the lower bobbin 22 are put together from above and below in such a state as to be rotatably accommodated in the empty space. Coil bobbin 20 formed as above
A cross coil 11 composed of a pair of coils that are orthogonal to each other is wound around the outer periphery of the instrument, thereby completing a cross coil type instrument movement. Note that the steel ball 33 is
Before the lower end of the thrust bearing 32 is inserted into the bearing recess 32a of the thrust bearing 32, it is press-fitted into the bearing recess 32a with a weak force in advance.

Thereafter, a beard ball 43a for fixing the hairspring 43 to the rotating shaft 40 is pressed into the upper end 41 of the rotating shaft 40 projecting out of the coil bobbin 20. Following the fixing of the hairspring 43, the pointer 13 is moved to the tip 41a of the rotating shaft 40.
And a cross-coil type instrument is assembled together with a dial and the like (not shown).

[0010]

A member to be fixed to the upper end 41 of the rotating shaft 40, such as the pointer 13 and the beard ball 43a, is press-fitted by, for example, a machine such as a press, and the coil bobbin 20 is inserted into the anvil of the press. Upper end 4 of rotating shaft 40
1 is fixed vertically upward, and a member to be press-fitted is press-fitted into the tip 41a of the rotating shaft 40 from above. At this time, based on the coil bobbin 20, the pointer 13, the beard ball 43a
The stroke of the press machine is controlled so that the height of the press stops at a predetermined height. However, the load required for press-fitting is, for example, 4
It is in the range of 9 to 147 N (5 to 15 kgf) and is not always constant.

A load for press-fitting is applied to the rotating shaft 40 as an axially downward thrust load.
The steel ball 33 in contact with the lower end 42 of the “0” is received. The bottom of the synthetic resin forming the bearing concave portion 32a holding the steel ball 33 is, for example, 0.2 to 0.2 due to the load at the time of press-fitting the beard ball 43 and the pointer.
Conventionally, when this load is large, this deformation is plastic deformation, and after the press-fitting step, the position of the rotating shaft 40 shifts from a predetermined position in the thrust direction, and the amount of the shift is also different for each product. There was a problem of scatter.

That is, such a permanent displacement of the rotating shaft 40 causes a brake fluid leak due to an increase in a clearance in the thrust direction of the rotating shaft 40 and an increase in wear of the bearing. Further, the space in the coil bobbin 20 and the magnet rotor 12 are
Since the clearance is configured to be small in order to effectively suppress the vibration caused by the brake fluid 23, the displacement of the rotating shaft 40 rubs due to the contact between the coil bobbin 20 and the magnet rotor 12, causing a risk of catching.

Accordingly, the present invention has been made in view of the above-mentioned conventional problems, and prevents the thrust bearing from being permanently deformed by press-fitting a member to be fixed to a rotating shaft when assembling the gauge. and its object is to provide a method for producing a cross-coil type instrument mu <br/> portion plane bets that can be ensured a stable thrust clearance.

[0014]

In order to achieve the above object, a method of manufacturing a movement for a cross-coil type instrument made according to the present invention is a method in which an upper and lower bobbin made of synthetic resin is butted.
A cross coil is wound around the coil bobbin
And the magnet rotor is rotated inside the bobbin.
Thrust that is rotatably housed and formed on the lower bobbin
The magnet box whose lower end is supported by a bearing
The upper end of the rotating shaft of the motor must not protrude out of the upper bobbin.
A cross-coil in which the pointer is press-fitted and fixed to the tip of the rotating shaft.
In the method of manufacturing a movement for a
Before butting the bobbin, form the thrust bearing
Larger than the pressure input when fixing the pointer at the bottom of the recess
Force from the thrust bearing to a predetermined value.
It is characterized by plastic deformation .

[0015]

[0016]

Further, the present invention is characterized in that the force for plastic deformation is applied via a steel ball received in the bearing recess and receiving the lower end of the rotating shaft.

Further, when the bearing recess is plastically deformed, the outside of the thrust bearing is received by a receiving jig having a shape adapted to the outside shape.

[0019]

In the above manufacturing method, the upper and lower bobbins are butted.
Before placing the finger on the bottom of the recess forming the thrust bearing
Apply a force larger than the pressure input when fixing the needle in advance, and
Plastic deformation so that the height from the thrust bearing is the specified value
Since it is hardened by pressing, the members to be fixed to the tip of the rotating shaft such as pointers and whiskers are pressed in in the subsequent instrument assembly process, and even if a thrust load for press fitting is applied to the steel ball, the bearing recess No further deformation occurs in the portion of the synthetic resin forming the above, and the relative dimensions of the coil bobbin and the magnet rotor can be stabilized.

[0020]

[0021]

Further, when the steel ball is press-fitted into the bearing recess, the outside of the thrust bearing is received by a receiving jig having a shape adapted to the shape of the outside of the thrust bearing, so that the other portion of the coil bobbin is received. This is effective in obtaining a stable relative dimension between the coil bobbin and the magnet rotor without applying unnecessary load to the coil bobbin.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a main part of Mubumen preparative method of manufacturing a cross coil type instrument according to the present invention may the non-essential parts are the same configuration as that described above with reference to FIG. 3, FIG. 5
The same reference numerals are given to the parts that have already been described, and the description thereof will not be repeated.

In the thrust bearing 32 shown in detail in FIG. 1, a steel ball 33 supporting a lower end 42 of the rotating shaft 40 is provided.
Is pressed into a bearing recess 32a formed in the lower bobbin 22 in a process before the coil bobbin is formed by abutting and combining with an upper bobbin (not shown). The steel balls 33 are press-fitted by, for example, a press machine, and the lower bobbin 22 is fixed to an anvil of a press machine (not shown) via a receiving jig 50 as shown in FIG. Is pressed into the bearing recess 32a.

In this embodiment, the steel balls 33
When press-fitting into the bearing recess 32a, the load is
a is controlled so as to be a load value, for example, 147 N (15 kgf) or more, which causes plastic deformation of the synthetic resin material forming the a. Also, the load from the steel ball 33 of the thrust bearing 32 to the upper bobbin of the lower bobbin 22 is controlled. Butt step 2
The press-fitting operation is performed so that the height up to 2a becomes the predetermined value A. As a result, the cross-coil type instrument movement according to the present invention has a certain amount of plastic deformation applied to the material at the bottom of the bearing recess 32a, so that the material at the bottom is hardened. The relative dimensions of the bobbin 20 and the magnet rotor 12 are stabilized.

That is, as described above, in the press-fitting step in assembling and manufacturing the instrument by assembling the movements with the members to be fixed to the tip 41a of the rotating shaft 40, such as the hands 13, the beard balls 43a, etc. ~ 147N
An axial downward thrust load in the range of (5 to 15 kgf) is applied, but the material of the bottom of the bearing recess 32a includes:
Since a load sufficiently larger than this load is applied and plastic deformation has been performed in advance, no further deformation occurs in the material of the bottom of the bearing recess 32a.
3. The above-described problem of the thrust clearance fluctuation caused by the press-fitting operation of the beard ball 43a or the like is solved.

FIG. 2 shows a receiving jig 50 used in the press-fitting step. The receiving jig 50 receives a lower portion of the thrust bearing 32 by a concave portion corresponding to the outer shape of the thrust bearing 32. Therefore, the receiving jig 50 is used for the thrust bearing 3.
The outer bobbin 2 serves to prevent an unnecessary concentrated load from being applied, and also to prevent an unnecessary load from being applied to other portions of the lower bobbin 22 and deforming the lower bobbin 22.

As shown in FIG. 2, the plastic deformation of the bearing recess 32a caused by the press-fitting of the steel ball 33 is caused, for example, by the contact surface 22a between the surface of the press-fitted steel ball 33 and the upper bobbin 21 of the lower bobbin 22. The dimension A after plastic deformation is always kept constant by managing the predetermined value A for the distance between. The predetermined value A is obtained in advance by trial manufacture, experiment, or other appropriate method, and the relative size between the bobbin 20 and the magnet rotor 12 can be properly maintained by performing correction at the design stage.

In the embodiment, the steel ball 33 for supporting the lower end of the rotating shaft 40 is supported by the thrust bearing 3 so as to be effective in preventing the thrust bearing 32 of the lower bobbin 22 from being worn.
Although it is accommodated in the second concave portion 32a, it may be omitted or replaced by another member by filling a brake fluid for preventing abrasion or the like.

In the description of FIGS. 1 and 2, when the steel ball 33 is pressed into the bearing recess 32a, the bearing recess 32a is pressed.
Although a load greater than that causing plastic deformation is applied to the synthetic resin material forming the steel ball, the plastic ball is previously generated by a jig rod before the steel ball 33 is press-fitted. You may make it press-fit with a small force which does not fall off.

In the case of a movement in which the steel ball 33 is not accommodated in the thrust bearing, the above-mentioned plastic deformation may be generated by a method as shown in FIGS.

That is, in the example of FIG. 3, as shown in FIG. 3A, a jig rod 60 having a flat tip is used to apply a load that causes plastic deformation to the synthetic resin material forming the bearing recess 32a. After the addition, as shown in FIG.
The rotary shaft 40, which is designated as a, is inserted, and the lower end of the rotary shaft 40 is directly received on the bottom surface of the bearing recess 32a. FIG.
In the example of (a), as shown in (a), a jig rod 70 having a spherical tip is used to apply a load that causes plastic deformation to the synthetic resin material forming the bearing recess 32a, and then (b)
As shown in FIG. 5, the rotary shaft 40 having a spherical tip 40a is inserted, and the lower end of the rotary shaft 40 is directly received on the bottom surface of the bearing recess 32a.

[0033]

According to the present invention, as described above ,
The upper and lower bobbins in the manufacture of the movement
Before, the above-mentioned pointer is attached to the bottom of the recess forming the thrust bearing.
Thrust bearings that apply a force greater than the force input during fixing
Plastic deformation so that the height from
In the subsequent instrument assembly process, the members to be fixed to the tip of the rotating shaft, such as pointers and whiskers, are pressed in, and the synthetic resin that forms the bearing recess even if the thrust load for press-fit is applied to the steel ball No further deformation occurs in the portion, and the relative dimensions of the coil bobbin and the magnet rotor can be stabilized, so that a stable thrust clearance can be secured after assembling the instrument.

[0034]

In addition, by receiving the outside of the thrust bearing with a jig during the press-fitting operation, unnecessary load is prevented from being applied to other portions of the coil bobbin, and the relative size between the coil bobbin and the magnet rotor is prevented. As a result, the press-fitting operation can be performed uniformly, and the workability can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-coil type instrument movement instrument according to the present invention.
FIG. 4 is a view showing a main part of a method of manufacturing

FIG. 2 is a side view showing a jig used in the manufacturing method of FIG.

3 is a diagram showing another embodiment which is a modification of a portion of the manufacturing <br/> method for producing a cross coil type instrument Mubumen bets FIG.

4 is a diagram showing yet another embodiment which is a modification of a portion of the manufacturing <br/> method for producing a cross coil type instrument Mubumen bets FIG.

FIG. 5 is a side view showing the structure of a general cross-coil type instrument movement, partially broken away.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Cross coil 12 Magnet rotor 13 Pointer 20 Coil bobbin 21 Upper bobbin 22 Lower bobbin 32 Thrust bearing 32a Bearing recess 33 Steel ball 40 Rotating shaft 41 Upper end of rotating shaft 41a Tip of rotating shaft 42 Lower end of rotating shaft 50 Jig

Claims (3)

(57) [Claims] 1. An upper and lower bobbin made of synthetic resin butted against each other.
When the cross coil is wound around the outer periphery of the formed bobbin
In both cases, the magnet rotor is rotatably housed in the bobbin.
And the thrust bearing formed on the lower bobbin
Of the magnet rotor, the lower end of which is bearing
The upper end of the shaft projects out of the upper bobbin,
Cross-coil instrument with a pointer press-fit at the tip of the instrument
In the method of manufacturing a movement, before the upper and lower bobbins are butted, the thrust bearing
Pressure input when fixing the pointer to the bottom of the recess forming
Force from the thrust bearing.
The plastic is characterized by being plastically deformed to a constant value.
A method for manufacturing a movement for a coiled instrument. 2. The apparatus according to claim 1, wherein said rotary shaft is accommodated in said bearing recess.
Due to the plastic deformation through the steel ball receiving the end
3. The crosco according to claim 2, wherein a force is applied.
Manufacturing method for il-type instrument movement. 3. The method according to claim 2, wherein the plastic deformation of the bearing recess is performed in advance.
The shape of the outside of the thrust bearing corresponds to the shape of the outside
2. Receiving by a receiving jig having the following.
Or the manufacture of the cross-coil type instrument movement described in 2.
Construction method.