JPH054246Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to electrical components such as variable resistors, and particularly to electrical components in which contacts are rolled on a substrate.

[Conventional technology]

Conventionally, a conductive contact is brought into elastic contact with the surface of a substrate on which a conductive pattern is formed, and desired resistance value adjustment or switching operation is performed by changing the contact position of the contact with respect to the conductive pattern. The electrical parts made by the manufacturer are widely known. This type of electrical component includes a type in which a contactor (slider) slides on a board, as typified by a sliding type variable resistor, etc.; There is also a type in which the contactor is rolled on the substrate, and in this type the contactor has sufficient rigidity for rolling.

[Problem that the invention attempts to solve]

By the way, as mentioned above, if a certain degree of rigidity is required for the contact that comes into contact with the conductive pattern on the surface of the substrate, the contact pressure is likely to be insufficient because the contact does not bend much, and the contact pressure is likely to be insufficient. If the part rides on dirt or dust on the board, the entire contact may tilt and cause poor conductivity, so measures are required to improve the reliability of contact.

Therefore, it is an object of the present invention to provide an electrical component in which the reliability of contact between a contactor rolling on the surface of a substrate and the surface of the substrate is improved.

[Means for solving problems]

In order to achieve the above object, the present invention includes a substrate on which a conductive pattern extending linearly is formed on the surface;
a conductive contact made of an arcuate plate material having spring properties and rolling on the surface of the substrate; a plurality of ribs extending along the arc surface of the contact and protruding toward the substrate; Similarly, slits extending along the arc surface and located between the ribs are provided, and the ribs are configured to roll on the conductive pattern along the direction in which they extend. .

[Effect]

According to the above means, since the ribs of the contact come into point contact with the conductive pattern on the surface of the substrate, the contact pressure is improved, and the independence of each rib is increased due to the presence of the slit, so that dirt on the substrate can be removed. Even if some of the ribs ride on dirt or dust, there is less risk that the remaining ribs will be separated from the substrate surface due to the influence.

〔Example〕

Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 is an exploded perspective view of a seesaw type variable resistor according to an embodiment of the present invention, FIG. 2 is a side view thereof, and FIG.
4 is a sectional view of a contact incorporated in this seesaw type variable resistor, and FIG. 5 is a plan view of the resistance board.

The seesaw type variable resistor shown in these figures has the first
As clearly shown in the figure, the operation key 1 and the leaf spring 2
It is mainly composed of a frame body 3, a contactor 4, a resistance board 5, and a mounting plate 6.

The operation key 1 is a resin molded product, and has approximately U-shaped side walls 1a protruding from both sides. When the concave groove 1b of the side wall 1a, which has an open end at the top, is snapped into the support pin 3a of the frame 3, the side wall 1a is rotatably supported by the support pin 3a, and the operation key 1 can be operated. Since the central portion 1c of the key 1 in the longitudinal direction is rotatably supported by the receiving portion 3b of the frame 3, the operation key 1 is slidably attached to the frame 3 by this snap-in.
That is, this operation key 1 has pressing parts 1 at both ends.
When either one of d is pressed, it rotates, and the maximum stroke is obtained when the back surface of the pressing portion 1d comes into contact with the regulating wall 3c of the frame 3. Further, a pair of knobs 1e protruding below the operation key 1 are always in contact with the vicinity of both ends of the contact 4 within the frame 3. In addition, the side wall 1 of the operation key 1
The pin 1f protruding from a is for locking a makeup knob (not shown) attached to the top surface of the operation key 1.

The leaf spring 2 is made of a thin metal plate such as phosphor bronze, and functions as a return spring for returning the operation key 1 to its initial position after being pressed. In other words, operation key 1
When the pressing part 1d is pressed, the arm part 2a of the leaf spring 2 located below is bent and the pressing part 1d is pressed.
Since spring pressure is applied to the back surface of the key 1, the operating key 1 is automatically returned to the initial position after a pressing operation due to the spring pressure. In addition, a square hole 2b is bored approximately in the center of this leaf spring 2.
The leaf spring 2 is positioned on the frame 3 by fitting the square projection 3d protruding from the upper surface of the frame 3 into the square hole 2b.

The frame body 3 is a resin molded product, and the support pins 3a protruding from both sides and the receiving portions 3b protruding from the top surface adjacent to each support pin 3a serve as mutually complementary support members to support the operation key 1. It is rotatably supported. That is, the cylindrical surface of the support pin 3a that contacts the bottom of the concave groove 1b of the operation key 1 and the cylindrical surface of the receiving portion 3b that contacts the back surface of the central portion 1c of the operation key 1 are set to be concentric with each other. , the operation key 1 is rotated around this cylinder center line O (see Fig. 3).
The operating key 1 is regulated in its upward or lateral position by a support pin 3a, and in its downward position by a receiving portion 3b. In other words, operation key 1
The downward external force that presses the central portion 1c is received by the entire frame 3 via the receiving portion 3b.
A leaf spring 2 is disposed on the upper surface of the frame 3, and a contact 4 and a resistance board 5 are installed inside the frame 3 from below.

The contactor 4 is made of a metal thin plate made of phosphor bronze or the like formed into an arc shape, and is in elastic contact with the surface of the resistance board 5 with the vicinity of both ends pressed by the knob 1e of the operation key 1. It has high rigidity and its arc shape hardly changes, as shown in Figure 3.
It rolls on the resistance board 5 in conjunction with the swinging of the operation key 1. This contactor 4 has a plurality of ribs 4a extending in the longitudinal direction and bulging toward the resistance board 5 side.
As a result, each rib 4a makes point contact with the surface of the resistance substrate 5 to ensure good contact pressure, and furthermore, a slit 4b extending in the longitudinal direction is formed between adjacent ribs 4a. Therefore, each rib 4a can be elastically deformed independently. Further, U-shaped locking pieces 4c are protruded from both sides of the center part of the contact 4.
When assembling into the frame 3, each locking piece 4c is inserted into the tapered groove 3e formed on the inner wall of the frame 3. 4 is positioned in the width direction and longitudinal direction. In addition, as shown in FIG. 3, the locking piece 4c
is located at the bottom of the tapered groove 3e when not operated, but when the operation key 1 is pressed and the contact 4 rolls on the resistance board 5, the locking piece 4c moves up and down within the tapered groove 3e. move.

On the surface of the resistance substrate 5, a strip-shaped resistor 7 extending in the longitudinal direction, a first current collector 8 and a second current collector 9 extending in the longitudinal direction on both sides of the resistor 7,
A central electrode 10 is patterned across the center of the resistor 7 and bridging the first and second current collectors 8,9. Further, lead parts 7a and 7b for terminal connection formed at both ends of the resistor 7, and lead parts 8a and 7b for terminal connection formed at both ends of the first current collector 8,
A lead terminal 11 is fixed to each of the terminals 8b by caulking. And on this resistance board 5,
A contact 4, which has ribs 4a formed at positions corresponding to the resistor 7 and the first and second current collectors 8 and 9, is in constant elastic contact with the resistor 7 and the first and second current collectors. Alternatively, since the second current collectors 8 and 9 are electrically short-circuited, when the contactor 4 rolls on the resistor substrate 5 and the contact position of the rib 4a with respect to the resistor 7 changes, the contact position of the rib 4a with respect to the resistor 7 changes. The resistance value changes as the temperature increases. Note that the first current collector 8 and the second current collector 9
and are electrically connected to each other via the central electrode 10, so the contacts 4 corresponding to both current collectors 8 and 9
It is sufficient that the outer rib 4a is in contact with either one of the current collectors. Furthermore, since the contactor 4 rolls due to the pressing operation of the operation key 1, the inner rib 4a of the contactor 4 corresponding to the resistor 7 comes into contact with the center electrode 10 when it is not operated. The resistance value is maximum.

The mounting plate 6 has four arms 6a and two legs 6b.
The leaf spring 2 and the resistance board 5 are integrated into the frame 3 via the mounting plate 6. That is, by bending the tips of each arm portion 6a of the mounting plate 6 inward, the leaf spring 2 is attached to the frame body 3.
The resistor board 5 fitted into the bottom of the frame 3 is supported and reinforced from the back side. Note that the leg portion 6b of the mounting plate 6
is for attaching this seesaw type variable resistor to a circuit board (not shown).

Next, the operation of the seesaw type variable resistor having the above configuration will be explained.

Now, when the pressing part 1d on the right side of FIG. 3 is pushed downward by a predetermined amount, the operation key 1 will rotate clockwise, and the contact 4 pressed by the knob 1e on the right side of the figure will rotate slightly on the resistance board 5. Due to this movement, the contact position of the contactor 4 on the resistance board 5 moves to the right in the figure, and the resistance value between the lead portion 7a and the lead portion 8a changes. That is, due to this pressing operation, the rib 4a of the contactor 4 that was in contact with the center electrode 10 of the resistor board 5 comes into contact with the resistor 7 on the right side of FIG. 5, and as the pressing stroke increases, As the contact position with the resistor 7 moves to the right in the figure, the resistance value between the lead portions 7a and 8a gradually decreases. When the back surface of the pressing portion 1d comes into contact with the regulating wall 3c of the frame 3, the regulating wall 3c
c functions as a stopper, and at this maximum stroke, the rib 4a moves from above the resistor 7 to the lead portion 7.
Since the contact position is moved above point a, the resistance value between lead portion 7a and lead portion 8a is approximately zero. Note that during this operation, the lead portion 7b
The resistance value between the lead portion 8b and the lead portion 8b does not change.

Further, the above-described pressing operation is performed on the arm portion 2a of the leaf spring 2.
This is done against the spring pressure of Automatically returns to the initial state. Note that when the operation key 1 is pressed, the contact 4 is pushed into the knob 1e and the radius of curvature becomes slightly larger.
A restoring force is generated in the contactor 4 to try to return its own radius of curvature, and this restoring force also contributes to the automatic return of the operation key 1 described above.

The above-mentioned resistance value change accompanying the pressing operation and automatic return after the operation are performed in the same way for the pressing part 1d on the left side of Fig. 3, and the resistance value is shown in Fig. 6 according to the stroke amount of each pressing part 1d. change like that.
In Fig. 6, when the stroke amount is 0 to 1 mm, the contact 4 is in contact with the center electrode 10, so the resistance value is maximum, and by pushing in either one of the pressing parts 1d, the stroke amount is changed from 1 mm to 2.2 mm. As the contact position of the contactor 4 moves on the resistor 7, the resistance value gradually decreases along the curve on the right or left side of the figure. Note that the stroke amount in FIG. 6 indicates the amount of descent of the tip of the pressing portion 1d, and the maximum stroke is within 3 mm.

Now, the seesaw type variable resistor described above was manufactured to adjust the zoom speed of a handy type video camera. The speed in the zoom pulling direction can be adjusted in section 1d. In other words, when you press either one of the pressing parts 1d with your finger, the speed of pushing (or pulling) the zoom will change steplessly according to the pressing stroke, and if the stroke amount is small, it will slow down and then When the amount is large, the zoom is pushed (or pulled) quickly. After the pressing operation, the pressing part 1d
When you release your finger from the button, the pressing portion 1d that has been lowered automatically returns to its initial position, so the zoom state does not change.

In this way, the arc-shaped contact 4 is placed on the resistance board 5.
By rolling the contactor 4, the contact position of the contactor 4 with respect to the resistor 7 can be greatly changed by a minute stroke of the pressing part 1d, and the operation key 1, the contactor 4, and the resistance board 5 etc. can be incorporated into the frame 3 in a laminated state, an extremely thin seesaw type variable resistor with a thickness of 10 mm or less can be realized. Therefore, even if this is installed in a handy type video camera, the space factor is good, and for example, a see-saw type variable resistor for zoom speed adjustment can be installed in the limited installation space above the battery box.

In addition, in the above embodiment, a support pin 3a that contacts the bottom of the groove 1b of the operation key 1, and a receiving portion 3b that is concentric with the support pin 3a and contacts the back surface of the center portion 1c of the operation key 1. support the operation key 1 in a mutually complementary manner, so the downward pressing force applied to the central part 1c is received by the entire frame 3 via the receiving part 3b, and this pressing force There is no risk that the support pin 3a will be damaged. Moreover, since the support structures are complementary to each other, there is no member that can be called the rotation shaft of the operation key 1, and therefore there is no need to form a through hole in the operation key 1 or the frame 3 for passing the rotation shaft. Another advantage is that the resin molding process is easy. Note that if the support pin 3a is cylindrical, a burr will be formed that will hinder the rotation of the operation key 1, but in the above embodiment, the upper half of the support pin 3a is formed narrow, so there is no need to worry about this. Moreover, since the top half of the tip of the support pin 3a is tapered, the operation key 1 can be snapped in very easily.

In addition, in the above embodiment, since the plurality of ribs 4a extending in the longitudinal direction are formed on the contactor 4, each rib 4a comes into point contact with the surface of the resistance board 5, so that a good contact pressure can be achieved. is obtained. Moreover, since the slits 4b are formed between adjacent ribs 4a, the independence of each rib 4a is increased, and therefore, some of the ribs 4a are prevented from riding on foreign objects such as dirt and dust on the resistor board 5. Even in this case, the contact between the remaining ribs 4a and the surface of the resistive substrate 5 is easily maintained, and the reliability of the contact is further improved.

Further, in the above embodiment, the first current collector 8 and the second current collector 9 are electrically connected to each other via the center electrode 10 on both sides of the resistor 7 in the longitudinal direction. Therefore, even if the contact 4 is tilted due to backlash during operation or foreign matter on the resistor board 5, the structure is such that poor conduction is unlikely to occur.
That is, as shown in FIG. 7, when the contactor 4 is tilted in a plane substantially perpendicular to the longitudinal direction of the resistance board 5, the contactor 4 is tilted toward the first current collector 8 (or the second current collector 8).
However, contact with the second current collector 9 (or first current collector 8) located on the opposite side of the resistor 7 is ensured.
There is little risk that the electrical connection between the resistor 7 and the first or second current collector 8, 9 via the contactor 4 will be undesirably interrupted.

Note that the seesaw type variable resistor can be widely applied as an adjustment electric component to various electronic devices other than video cameras.

[Effect of idea]

As explained above, according to the present invention, the contact pressure is increased by providing the ribs on the contact, and the independence of each rib is increased by the interposition of the slits, so that the contact pressure is increased. The reliability of the contact between the conductive pattern and the conductive pattern on the surface of the substrate is greatly improved.

[Brief explanation of the drawing]

The figures are all for explaining one embodiment of the present invention, and FIG. 1 is an exploded perspective view of a seesaw type variable resistor, FIG. 2 is a side view thereof, FIG. 3 is an explanatory diagram of the operation, and FIG. The figure is a cross-sectional view of the contact included in this seesaw type variable resistor, Figure 5 is a plan view of the resistance board, Figure 6 is a characteristic diagram showing the correlation between stroke and resistance value, and Figure 7 FIG. 2 is a cross-sectional view showing a contactor tilted on a resistive substrate. 4... Contact, 4a... Rib, 4b... Slit, 5... Resistance board, 7... Resistor.

Claims (1)

[Scope of utility model registration request] It is equipped with a substrate on which a linearly extending conductive pattern is formed, and a conductive contact made of an arcuate plate material having spring properties that rolls on the surface of the substrate. A plurality of ribs extending along the conductive pattern and protruding toward the substrate side and slits extending along the arc surface and positioned between the ribs are respectively provided, and the ribs roll on the conductive pattern along the extending direction. An electrical component characterized by being configured to move.