JPH11285231A - Actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the waterproofing capability of a case connecting part as well as resin charging efficiency and quality. SOLUTION: A rotor 5 for driving the rotation of a control rod 8a, and a stator 6 for driving the rotor 5 are disposed in a space surrounded by an upper case 1 and a lower case 2. The whole periphery of a fitting part between the upper case 1 and the lower case 2 is welded by means of ultrasonic waves, and the annular groove of its outside is filled with adhesive resin for sealing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an actuator for adjusting a damping force of a shock absorber.

[0002]

2. Description of the Related Art In a conventional shock absorber of variable damping force, an actuator such as a step motor for driving a valve for switching an oil passage inside the shock absorber to adjust the damping force is generally provided on the vehicle body side of the shock absorber. It is attached near the connecting part to the actuator, and among them, the waterproof structure for preventing the intrusion of water into the actuator is taken.
There is the one disclosed in Japanese Patent No. 13428.

This is configured as shown in FIG. 6, in which a step motor is arranged in a space surrounded by an upper case 1 and a lower case 2, and is connected to an output shaft 8 protruding from a central portion of the lower case 2. When the control rod 8a of the damping force variable shock absorber controls the current of the stator 6 to rotate the rotor 5 stepwise, the rotor 5 rotates accordingly to change the damping force.

[0004] An annular groove 9 having a V-shaped cross section is formed in a fitting portion between the upper case 1 and the lower case 2.
The grooves 9 are filled with an adhesive resin 3 and bonded to each other to prevent water or the like from entering from outside through the fitting portions.

[0005]

However, in this case, when filling the adhesive resin with the upper case 1 and the lower case 2 fitted together, the filling is performed while the fitting portion is completely adhered. Otherwise, a portion of the resin may enter the inside of the case through the fitting gap. In severe cases, the rotation of the rotor 5 may not be smoothly performed by the resin.

In order to prevent this, it is necessary to fill the resin while firmly fixing the upper case 1 and the lower case 2 tightly. However, such a work requires a considerable amount of time and is not stable in quality. There is a problem that a decline in sex is inevitable.

The object of the present invention is to solve these problems.

[0008]

According to a first aspect of the present invention, there is provided an actuator in which a rotor for driving a control rod and a stator for driving the rotor are arranged in a space surrounded by an upper case and a lower case. Ultrasonic welding is performed on the entire periphery of the fitting portion between the upper case and the lower case, and the outer annular groove is filled with an adhesive resin and sealed.

According to a second aspect of the present invention, a surplus portion extending in a fitting length direction is formed on a fitting surface between the upper case and the lower case.

[0010]

According to the first aspect of the present invention, since the upper case and the lower case are welded in advance, and the annular groove is filled with the adhesive resin in a completely sealed state, the resin filling operation is easy. It is highly efficient and can reliably prevent the resin from entering the inside of the case. In addition, since it is double sealed by welding and resin, it is also excellent in waterproofness.

According to the second aspect of the present invention, even if the fitting length between the upper case and the lower case has an accurate variation due to the extra thickness in the fitting length direction of the fitting surface, good ultrasonic welding is always achieved. Is possible, and the stability of quality is increased.

[0012]

1 to 4 show an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an upper case, 2 denotes a lower case, in which a rotor 5 and a stator 6 are disposed. The rotor 5 has an output shaft 8 for adjusting a damping force of a shock absorber. The control rod 8a is connected, and the rotation of the rotor 5 changes the damping force of the shock absorber.

In a fitting portion 10 of the upper case 1 and the lower case 2 which are both formed into a cylindrical shape with a bottom, the upper case 1 is provided with a flange-shaped enlarged portion 11 on the outside,
A vertical cylindrical portion 12 is provided in the lower case 2, and the cylindrical portion 12 is fitted on the inner periphery of the enlarged diameter portion 11, and is subjected to ultrasonic welding over the entire periphery of the fitting surface.
3, the upper case 1 and the lower case 2 are connected.
Further, the outer annular groove 14 is filled with an adhesive resin to form a resin adhesive portion 15, thereby further firmly connecting the upper case 1 and the lower case 2.

The connection between the upper case 1 and the lower case 2 is performed after all the components constituting the step motor, that is, the rotor 5 and the stator 6 are incorporated in the internal space.

In this manner, in a state where the upper case 1 and the lower case 2 are fitted together, ultrasonic welding is performed on the entire periphery of the fitting surface, and is fixed by the welded portion 13, and thereafter, from the outside. Since the bonding resin is filled, the filling surface of the upper case 1 and the lower case 2 is completely sealed when the resin is filled, so that there is no possibility that the resin may enter the inside.

In addition, since the upper case 1 and the lower case 2 are integrated when the resin is filled, it is not necessary to support the fitting surfaces so that the fitting surfaces are in close contact with each other. The quality is also stable. Also,
As described above, the fitting surface is formed by the ultrasonic welding portion 13 and the resin bonding portion 15.
With the double seal structure described above, the waterproofness becomes extremely high, and the reliability is improved.

As shown in FIG. 5, an enlarged diameter portion 11 of the upper case 1 is provided on a fitting surface between the upper case 1 and the lower case 2.
Is formed inside the inner peripheral step, and a thin surplus portion 11A for ultrasonic welding extending in the fitting length direction is formed, even if the actual fitting length (depth) varies. Surplus part 11 surely
A can be fitted and ultrasonic welding can be performed, and the stability of quality can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a cross sectional view of the same.

FIG. 3 is an enlarged view of a case fitting portion before welding.

FIG. 4 is an enlarged view of the same after welding.

FIG. 5 is an enlarged view showing another example of a case fitting portion before welding.

FIG. 6 is a sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper case 2 Lower case 5 Rotor 6 Stator 11 Large diameter part 12 Cylindrical part 13 Ultrasonic welding part 14 Annular groove 15 Resin welding part

Claims (2)

[Claims] An actuator in which a rotor for driving a control rod and a stator for driving the rotor are arranged in a space surrounded by an upper case and a lower case. An actuator, wherein the periphery is ultrasonically welded, and an outer annular groove is filled with an adhesive resin and sealed. 2. The actuator according to claim 1, wherein a surplus portion extending in a fitting length direction is formed on a fitting surface between the upper case and the lower case.