GB2026273A - Pushbutton tuner - Google Patents

Abstract

A pushbutton tuner wherein a plurality of tilting actuating links 1 are provided for a slide member 12 for causing cores to move in-and-out of coils and the actuating links 1 are adapted to engage setting pins 4 of frequency regulating members 3 respectively, which are provided on button slides 2 actuatable by push buttons 15, respectively, to effect a selection operation. A pivotal pin 5 fitted in a hole formed in each of the frequency regulating members 3 has a tapering portion 5a and each of the setting pins 4 also has a tapering portion 4a at a portion where the setting pin 4 engages the actuating links 1 associated therewith. For fine tuning the slide 12 can be adjusted by a shaft (22, Fig. 5) and gears (18, 20). <IMAGE>

Description

SPECIFICATION Pushbutton tuner This invention relates to a pushbutton tuner and more particularly to a mechanism for eliminating a tuning deviation or error of the pushbutton tuner.

Generally, in a pushbutton tuner, cores are moved in-and-out of coils by a core slide, the core slide is actuated by actuating links provided at positions interior of a tuner housing, namely, rearward of button slides, and the actuating links are actuated by setting pins provided on frequency regulating members, respectively, which are in turn provided on the button slides, respectively. Base end portions of the frequency regulating members are connected to the button slides by pivotal pins, respectively. Either of the setting pin and the pivotal pin has a cylindrical periphery extending in parallel with the axis thereof.

Upon careful observation and study of such a known pushbutton tuner by the inventors of the present invention, it has been found that the known pushbutton tuner involves a possibility of tuning error (F deviation) in an actual selection operation and has such a disadvantage that a desired turning cannot be always obtained.

The invention has been achieved upon study of these facts. The study has been first made as to why and how such tuning deviation or error is caused in the pushbutton tuner and it has revealed that while the frequency regulating member is fastened and held face to face by a head of the pivotal pin of cylindrical shape, it may possibly be rotated and since the angle of the frequency regulating member is required to be reset or changed, gaps are left around the periphery of the pivotal pin and from the face of the head, respectively, so that the possibility of tun- ing deviation or error is further increased.As to the setting pin, when it is brought into engagement with the edges of the actuating links for carrying out a selection operation, the frequency regulating member is caused to receive a considerable resistance at the tip end portion thereof under an unstable state at the base end thereof. Therefore, the setting pin will possibly disengage from the button slide so that stable and accurate selection operation cannot be expected.

It is therefore an object of the invention to provide a pushbutton tuner having a mechanism for positively eliminating a tuning deviation or error in the pushbutton tuner.

In accordance with the invention, there is provided a pushbutton tuner comprising a plurality of tuning coils; cores adapted to move in-and-out of the coils, respectively; a slide member for displacing said cores relative to said coils, respectively; a plurality of pairs of actuating links engaged with said slide member, said actuating links of each pair being crossed with each other at the point where that pair of links engage the slide member and pivotal relative to each other; a plurality of button slides; push buttons provided on the button slides, respectively; frequency regulating members pivotally connected to the button slides, respectively; setting pins provided on said frequency regulating members, respectively, and adapted to act on respective pairs of actuating links adjacent the crossing points thereof; and pivotal pins for pivotally connecting said frequency regulating members to said button slides, respectively, each of said pivotal pins being formed with a head and an adjacent tapering portion pivotally connecting the respective frequency regulating member to the respective button slide.

Fig. lisa partly cut away perspective view of one form of a pushbutton tuner in accordance with the present invention.

Fig. 2 is a fragmentary partly cut away plan view of the pushbutton tuner illustrated in Fig. 1.

Fig. 3 is a sectional view of a button slide and a frequency regulating member employed in the pushbutton tuner.

Fig. 4 is an enlarged sectional view of a pivotal pin employed in the pushbutton tuner.

Fig. 5 is a schematic plan view of another form of a pushbutton tuner in accordance with the present invention.

A general arrangement of a pushbutton tuner is as illustrated in Fig. 1. A baseplate 10 has at one side thereof a coil seat 11. Coils (not shown) are mounted on the coil seat 11 and cores are adapted to enter or exit relative to the coils by a displacing member (not shown). The displacing member is in turn actuated by a slide member 12 mounted on the baseplate 10. A pin 13 provided on the slide plate 12 is engaged at elongated slots 14, 14, with rear ends of actuating links 1, 1, which are tilted so as to cross each other as can be seen from Fig. 2. The actuating links 1, 1 each have an engaging edge 1 a which is adapted to engage a setting pin 4 of a frequency regulating member 3. The frequency regulating member 3 is provided on each of button slides mounted on the baseplate. Thus, the setting pin 4 can carry out a selection operation.

In accordance with the invention, the frequency regulating member 3 is pivotally connected to the button slide 2 at a tapering portion 5a adjacent to a head portion of a pivotal pin 5 as illustrated in an enlarged scale in Fig. 4. More specifically, the tapering portion 5a of the pivotal pin 5 abuts against a wall of a slot 3a formed at the base portion of the frequency regulating member 3. A similar truncated conical tapering portion 4a is formed also on the setting pin 4 provided at the tip end portion of the frequency regulating member at least at a portion where it contacts the actuating links 1, 1.

In the pushbutton tuner as illustrated, 6 is a resilient plate whose rear end rests on the tip end portion of the frequency regulating member 3 and whose forward end rests on a slide metal 7 which is attached to the button slide 2 and adapted to slide conjointly with a push button 15. When the slide metal 7 is pushed inwardly with the push button 15, the forward end of the resilient plate 6 is raised and the rear end of the resilient plate 6, which is secured intermediate thereof to the button slide 2, holds and locks the free end of the frequency regulating member 3. On the other hand, when the slide metal 7 is pulled forwardly the locking is released so that the set angle of the frequency regulating member 3 with the button slide 2 may be changed suitably in the same manner as known.

In accordance with the arrangement of the present invention, the frequency regulating member 3 is pivotally connected through engagement of the tap ering portion 5a of the pivotal pin 5 with the wall of the slot 3a to form an angular connection between the pivotal pin 5 and the wall of the slot 3a. Accord ingly, the connection can be tight allowing the set angle of the frequency regulating member 3 to be adjusted. The frequency regulating member 3 thus tightly fastened as illustrated in Fig. 4 is stable with respect to the button slide 2 producing no looseness Moreover, please note that the setting pin 4 provided at the tip end portion of the frequency regulating member3 is also formed with the tapering portion 4a of truncated conical shape.This tapering portion 4a is brought into contact with the engaging edge 1 a of the actuating link 1 for carrying out selection operation and causes the cores to move relative to the coils through the slide member 72. During the actuation of the actuating link 1, a force component for pressing the frequency regulating member 3 against the button slide 2 is exerted by the tapering portion 4a. Accordingly, in the resistive operation of the actuating link 1, the tip end portion of the frequency regulating member 3 will not disengage any more. Furthermore, as mentioned above, the fre- quency regulating member 3 is stably held by means of the pivotal pin 5 so that the frequency regulating member 3 is always in a properly set position when the selection operation is carried out.Therefore, accurate selection is attained without causing tuning deviation or tuning error. Furthermore, such a mechanism for eliminating the tuning deviation is simple in construction and is by no means obstruc tire to resetting of the frequency regulating member 3 or even more convenient for the resetting.

In general, a pushbutton tuner is required to have a rotary fine tuning mechanism operable by manual handling as well as a tuning mechanism operable by push buttons. As known, this fine tuning mechanism is mounted on left or right side of the pushbutton tuner housing depending upon the position in a car where the mechanisms is mounted. However, the design of the pushbutton tuner such as arrangement of a circuit board for the five tuning mechanism and other components should be greatly changed depending upon which side the mechanism is mounted on. Accordingly, a manufacturing line for the pushbutton tuners should be changed depending upon the types of the pushbutton tuners as mentioned above and the manufacturing line adapted for either one of the types of the pushbutton tuner can not be used for another type of pushbutton tuner.

Thus, the manufacturing line is selected according to a manufacturing schedule of desired type of push button tuners.

Therefore, in another preferred form of a pushbutton tuner in accordance with the invention as illustrated in Fig. 5, the pushbutton is specifically adapted so as to overcome the problem.

A core seat 17 is provided at a position adjacent to one end of the slide member 12 for moving cores in-and-out of coils 16. The core seat 17 has a rack 18 engageable with a pinion 20 formed at a forward portion of an operation mechanism 19 for rotary fine tuning. The operation mechanism 19 is comprised of a train of gears and other components integraily assembled with an auxiliary mechanism baseplate 21 and a rotary operation shaft 22 and a rotary operation shaft sleeve 23 which are projected forwardly from a seat 25 formed on a baseplate. Another end of the slide member 12 has an extended portion 24 extended towards another seat 25' formed also on the baseplate 10. The extended portion 24 has an auxiliary rack 18' formed thereon symmetrically with the rack 18.

In accordance with this embodiment, when the fine tuning operation mechanism 19 is mounted on the left side of the pushbutton tuner as illustrated in a solid line in Fig. 5, it is apparent that smooth operation can be attained in the pushbutton tuner with the fine tuning operation mechanism mounted on the left side. On the other hand, when a fine tuning operation mechanism 19'is required to be mounted on the right side, the fine tuning operation mechanism 19' integrally assembled with an auxiliary mechanism baseplate 21' is mounted on the seat 25' as illustrated in a phantom line in Fig. 5 and pinion 20' is meshed with the auxiliary rack 18'.

Thus, it is possible for the present embodiment to adapt for either type of pushbutton tuner simply by placing the operation mechanism on the left or right side of the tuner. No change in design of coils, cores, a circuit board, a slide member, etc. is required any more. Accordingly, either type of pushbutton tuner can be manufactured according to a single manufacturing line.

Claims (5)

1. A pushbutton tuner comprising a plurality of tuning coils; cores adapted to move in-and-out of the coils, respecitively; a slide member for displacing said cores relative to said coils, respectively; a plurality of pairs of actuating links engaged with said slide member, said actuating links of each pair being crossed with each other at the point where that pair of links engage the slide member and pivotal relative to each other; a plurality of button slides; push buttons provided on the button slides, respectively; frequency regulating members pivotally connected to the button slides, respectively; setting pins provided on said frequency regulating members, respectively, and adapted to act on the respective pairs of actuating links adjacent the crossing points thereof; and pivotal pins for pivotally connecting said frequency regulating members to said button slides, respectively, each of said pivotal pins being formed with a head and an adjacent tapering portion pivotally connecting the respective frequency regulating member to the respective button slide.

2. A pushbutton tuner as claimed in claim 1, wherein the pivotal pins are mounted on their respective button slides and the frequency regulating members haveopenings through which their rests pective pivotal pins extend, first sides of the frequency regulating members engaging their respective button slides, and the other sides of the frequency regulating members around their openings engaging the tapering portions of their respective pivotal pins.

3. A pushbutton tuner as claimed in claim 1 or 2 wherein said setting pins each have a tapering portion for engagement with the pair of actuating links adjacent the crossing point thereof.

4. A pushbutton tuner as claimed in any preceding claim, which further comprises fine tuning means and wherein either end of said slide member has a portion for engaging the fine tuning means.

5. A pushbutton tuner substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.