JPH0138837Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a rotary switch that is small in size and capable of opening and closing a large current.

Conventionally, as a small-sized rotary switch capable of opening and closing a large current, a structure shown in Japanese Utility Model Publication No. 11433/1983 filed by the same applicant as the present application has been devised and developed. The internal structure of this switch is shown in FIG. This conventional structure has features such as being able to make the switch flat, that is, having a small thickness, and also being able to obtain strong contact force at the initial stage.

However, the conventional switch shown in FIG. 1 has a structure in which a plate-shaped movable contact piece 1 is directly stacked on a switching plate 2, and the top thereof is pressed by a taper spring 3. Since the purpose is to achieve moderation in the switching of the switch, it needs to be made with considerably strong force. In the end, movable contact piece 1
The part pressed by the taper spring 3 in is in complete contact with the switching plate 2, and it is not possible to ensure a sufficient length for the elasticity to work effectively up to the contact point. In addition, as the shaft 4 of the switch is rotated to open and close the switch, it is unavoidable that the plate-shaped movable contact will fatigue and wear out at an early stage.Furthermore, the large current switching will cause wear and tear (of the movable contact). (The lower part wears out and the height decreases), and when these factors overlap, the contact force of the contact rapidly decreases, and the heat generation and temperature rise in that part become excessive, resulting in the product becoming unusable. The drawback was that the number of lifetimes was significantly limited.

Furthermore, in the conventional type, as mentioned above, the movable contact piece is directly stacked on the switching plate and the top is pressed by a strong taper spring. The force pressing the piece becomes excessive, and as a result, the resistance force due to the friction phenomenon of that part has a considerable effect, and the movement becomes slow when switching the switch open/close (by rotating the shaft), and the movable contact There was also the problem that the fixed contacts fixed to the strips would stop just short of reaching a completely predetermined position for each step, resulting in a lack of contact stability.

The present invention has been made to improve the above-mentioned difficulties of the conventional technology, and therefore, the purpose of the present invention is to provide a contact force that is sufficiently stable for a long period of time even after the switch is opened and closed. It is an object of the present invention to provide a novel rotary switch with a long service life, which reduces heat generation, temperature rise, and increase in contact resistance at contact parts.

The above object of the present invention is to form a wavy protrusion on a switch base and place a switching plate having a plurality of spherical protrusions on its lower surface or with a plurality of spheres interposed therebetween on the wavy protrusion; A movable contact piece having elasticity is loosely inserted onto the switching plate and above the switching plate via a taper spring into the shaft inserted into the switch base, and the switching plate and A rotor base is placed in a relationship that ensures rotation integrally with the movable contact piece,
The switching plate, the taper spring, the movable contact piece, and the rotor base are restrained around the shaft by a stop ring or the like, and a common contact and a movable contact are protruded from both ends of the movable contact piece, and fixed to the switch base. A common contact piece and a fixed contact piece are arranged around the common contact point and a fixed contact piece corresponding to the common contact point and the movable contact point, and the movable contact piece is arranged between the inner lower surface end of the rotor base and the upper end surface of the movable contact piece. This is achieved by a rotary switch characterized in that an auxiliary coil spring is interposed at the position where the contact is fixed.

Next, a preferred embodiment of the present invention will be specifically explained with reference to the drawings.

FIG. 2 is a sectional view showing an embodiment of the rotary switch according to the present invention, and FIG. 3 is an exploded perspective view of the same embodiment. In the figure, reference number 10 indicates a switch base formed of an insulator, and in the center of the switch base 10 is a hole 11 through which a shaft 20 having a rectangular portion 21 and a groove 22 at its tip is inserted. A wavy protrusion (cam surface) 12 is formed on the peripheral surface of the hole 11 to maintain the switching operation and moderation of the switch. A common contact piece 13 and a plurality of stationary contact pieces 14 are also fixedly attached to the peripheral portion of the surface of the switch base 10 by, for example, caulking rivets. The common contact piece 13 is an annular contact piece 13 provided around the wavy protrusion 12.
It is formed integrally with a. Reference numeral 30 indicates a switching plate, and a hole 31 into which the shaft 20 is loosely inserted (loosely fitted) is formed in the center of the switching plate 30, and troughs of the wavy projections 12 are formed on both sides straddling the hole 31. A plurality of holes 32 are provided for interposing a plurality of balls 40 therebetween. The switching plate 30 is also provided with a plurality of tongue pieces 34 for gripping and engaging an ear piece 33 and a rotor base, which will be described later.
In order to slightly lift the lower surface of the movable contact piece (described later) while rotating the shaft to open and close the contact, its tip is slightly curved upward.
50 is a tapered spring for obtaining switching moderation of the switch. Reference numeral 60 indicates a movable contact piece formed of an elastic body, and the movable contact piece 60 includes a hole 61 into which the shaft 20 is loosely inserted (loosely fitted), and the annular contact piece 13a.
A common contact 62 is always in contact with the rotor, a movable contact 63 is selectively in contact with a plurality of fixed contact pieces 14, and a plurality of ears 64 are engaged with a rotor base, which will be described later. 70 indicates a rotor base, and the shaft 2 is located in the center of the rotor base 70.
A hole 71 into which the 0 is inserted and fixed, a boss portion 72 communicating with the hole 71, and a raised portion 73 for fixing the stop ring 80 are formed, respectively. The rotor base 70 also includes an engaging portion 74 that grips and engages the lug 64 of the movable contact piece 60, and a movable contact 6.
A protrusion 75 for interposing a spring 90 between the protrusion 65 provided at a portion corresponding to 3 is provided.

The above members are first inserted into the shaft 20 through the switch base 10 through the bushing 100, then the ball 40, the switching plate 30, and the taper spring 5.
0, the movable contact piece 60 is placed or inserted in this order, and finally the rotor base 70 is inserted into the tip of the shaft 20 with a spring 90 interposed between it and the movable contact piece 60,
By fitting the stop ring 80 into the groove 22 of the shaft, the rotor base 70 is attached to the shaft 20.
to be fixed. Then, it is assembled as shown in FIG.

Here, when rotating the shaft 20, the rotor base 70 fixed to the shaft 20 is rotated together with the switching plate 30 and the movable contact piece 60,
As a result, the switching operation of the switch is performed.

In this invention, the movable contact piece is not placed on top of the switching plate, but is placed on the underside of the rotor base, so the strong force of the taper spring is dedicated to obtaining switching moderation and acts only on the switching plate. , a perfect switching state can be obtained without causing any slowness in the switching movement due to unnecessary frictional phenomena caused by the tapered spring.

In addition, the movable contact piece is not placed on the switching plate as described above, but is placed on the rotor base side.
In the movable contact piece up to the contact point at the end,
It is very preferable to ensure a length that allows the elasticity to act sufficiently effectively, thereby eliminating fatigue and fatigue of the movable contact piece.

Furthermore, on the movable contact side, which generates arcs and wears out due to switching of large currents, a coil spring is installed between the movable contact piece and the rotor base to always supplementally press the movable contact. Therefore, even if the contact points wear out, a stable contact force will be applied, resulting in a long-life switch with low contact resistance and low temperature rise.

As a result of the above-mentioned structural changes, in the present invention, a sufficiently stable contact force can be obtained over a long period of time, and a long life with less heat generation, temperature rise, and contact resistance increase in the contact area, and switching opening/closing can be achieved. A very good small rotary switch with no slow contact movement can be obtained.

Although not directly related to the gist of the present invention, the method of fixing the rotor base to the shaft is different from that of the switch described in the above-mentioned Japanese Utility Model Publication No. 11433/1983, and the figure shows a case in which a stop ring is used.
However, the present invention is not necessarily limited to this illustrated example. In this example, the stop ring has a rectangular hole large enough to almost match the rectangular part of the shaft and be inserted through it, and each part is inserted and assembled, and the stop ring is fitted to the position of the shaft groove while pressing the rotor base. Then rotate it 90 degrees and release your hand that was pressing the rotor base to complete the fixation. Note that the raised portion on the upper surface of the rotor base is for preventing rotation of the stopper.

Further, in the illustrated embodiment, a ball is disposed between the switching plate and the wavy protrusion of the switch base, but instead of the ball, a spherical protrusion may be provided on the switching plate itself.

The switch base is not necessarily limited to the illustrated embodiment; for example, it may have a shape with an upright peripheral wall. Furthermore, parts such as the switching plate are not necessarily limited to the shapes shown in the drawings.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view of a conventional rotary switch, FIG. 2 is a sectional view showing an embodiment of the rotary switch according to the present invention, and FIG. 3 is an exploded perspective view of the same embodiment. 10... Switch base, 11... Hole, 12...
... Wave-like projection, 13 ... Common contact piece, 13a ... Annular contact piece, 14 ... Fixed contact piece, 20 ... Shaft,
21... Rectangular portion, 22... Groove, 30... Switching plate, 31, 32... Hole, 33... Ear piece, 34...
Tongue piece, 40... Ball, 50... Taper spring, 60...
...Movable contact piece, 61...Hole, 62...Common contact, 6
3...Movable contact, 64...Ear piece, 65...Protrusion,
70... Rotor base, 71... Hole, 72... Boss portion, 73... Protruding portion, 74... Engaging portion, 75...
... Convexity, 80 ... Stop spring, 90 ... Coil spring, 100 ... Bushing.

Claims (1)

[Scope of utility model registration request] A shaft having a wavy protrusion formed on a switch base, a switching plate having a plurality of spherical protrusions on its lower surface or having a plurality of balls interposed therebetween placed on the wavy protrusion, and inserted into the switch base. A movable contact piece having elasticity is loosely inserted onto the switching plate and the switching plate via a taper spring, and the movable contact piece rotates together with the shaft and rotates integrally with the switching plate and the movable contact piece. The switching plate, taper spring, movable contact piece, and rotor base are restrained around the shaft by a stop ring or the like, and a common contact and a movable contact are placed on both ends of the movable contact piece. The contacts are fixed in a protruding manner, and a common contact piece and a fixed contact piece are arranged around the switch base in correspondence with the common contact and the movable contact, and furthermore, a common contact piece and a fixed contact piece are arranged in correspondence with the common contact and the movable contact, and the inner and lower ends of the rotor base are connected to each other. A rotary switch characterized in that an auxiliary coil spring is interposed between the upper end surface of the movable contact piece and the position where the movable contact is fixed.