JP2568650B2 - Two-axis rotary encoder - Google Patents

Description

The present invention is mainly used for editing video equipment,
The speed mode switching signal at the time of tape fast-forward operation on the outer shaft
The present invention relates to a two-axis rotary encoder that generates a pulse signal for frame advance of a tape on an inner shaft.

2. Description of the Related Art A conventional technique will be described with reference to a two-axis rotary encoder shown in FIGS. FIG. 6 is a side sectional view, and FIG.
The figure is a plan view of the fixed contact of the two-axis rotary encoder of FIG.

6 and 7, reference numeral 1 denotes a base portion made of a material such as zinc die-casting. A cylindrical bearing portion 2 is provided at the center of the upper surface of the base portion. The outer peripheral portion has a thread 2 'for attachment to the device. The outer operation shaft 3 is made of insulating resin and has a cylindrical fitting portion 3 '.
The upper extension forms a mounting portion 3 ″ for the external operation knob 4, and an external contact substrate 6 holding an external rotation elastic contact 5 is integrally formed at the lower end portion. The inner operation shaft 7 fitted and held in the hole so as to be independently rotatable,
The upper extension forms a mounting portion 7 'for the inner operation knob 8, and an inner contact board 10 made of an insulating material holding the inner rotation elastic contact 9 is attached to the lower portion so as to rotate together.
Positioning in the vertical direction is performed by two washers 11 and 12.

A cylindrical wall portion extending downward from the outer periphery of the base portion 1;
13 has a plurality of concentric fixed contacts 14 and 1
A contact board 16 made of an insulating material having 4 'and 15,15' is attached to the fixed contacts 14, 14 'and 15, 15'. The inner rotation elastic contacts 9 protruding from the inner contact board 10 are in elastic contact with each other. In FIG. 7, the hatched portions are exposed on the surface at the fixed contacts 14, 14 'and 15, 15', and the solid portion is covered with an insulating film so as not to be exposed on the surface at the lead portion to the terminal. In this case, by rotating the outer operation shaft 3 via the outer operation knob 4, a signal for switching the video tape fast-forward speed mode between the outer rotating elastic contact 5 and the fixed contacts 14, 14 'is output. By rotating the inner operation shaft 7 through the, a pulse signal is generated between the inner rotation elastic contact 9 and the fixed contacts 15 and 15 'to generate a frame feed signal of the video tape, and each fixed contact is Some can be taken out from the connected terminal portions 17 and 18.

However, in the above-described conventional two-axis rotary encoder, the cylindrical outer operation shaft 3 is fitted and held by the cylindrical bearing portion 2 on the upper surface of the base portion 1, and the center hole of the outer operation shaft 3 is further formed. Since the inner operating shaft 7 is fitted and held by the portion, the frequently used inner operating shaft 7 is double-fitted between the bearing portion 2 and the outer operating shaft 3 and between the outer operating shaft 3 and the inner operating shaft 7. Due to the gap, there is a disadvantage that radial backlash (radial backlash) is large. Further, in order to suppress this drawback, there is a problem that the above-mentioned two fitting gaps are reduced, the rotational torque is increased, and the outer operation shaft 3 and the inner operation shaft 7 rotate together without independent rotation. There was also.

On the surface of one fixed contact board 16, inner circular fixed contacts 15 and 15 'for the inner rotating elastic contact 9 are provided on the inner periphery, and outer circular fixed contacts 14 and 15 for the outer rotating elastic contact 5 are provided on the outer side. , 14 ′ need to be arranged concentrically, and for an encoder of a complicated type in which the external contact is rotated by the external operation shaft 3 or the internal operation shaft 7, the outer shape of the entire encoder becomes large. There was also.

An object of the present invention is to provide a two-axis rotary encoder that solves such a conventional problem.

Means for Solving the Problems According to the present invention, a base portion is disposed at a lowermost portion, and a fixed contact board is disposed above the base portion. The holes are separately fitted and held, and the rotating contact plates attached to the inner and outer operation shafts are arranged on the lower surface and the upper surface of the fixed contact substrate, respectively.

Operation Therefore, according to the present invention, the frequently used inner operation shaft is directly fitted and supported by the support shaft extended from the base portion of the base, so that the fitting gap is one place, and the radial play of the inner operation shaft is reduced. (Radial play) becomes smaller. Further, since the inner operation shaft and the outer operation shaft are fitted and held by separate means, even if the fitting gap is reduced to further suppress the radial play of these operation shafts, they do not rotate together.

In addition, since the rotating contact plates of the inner and outer operation shafts are arranged separately on the lower surface and the upper surface of the fixed contact substrate, the outer diameter of the contact substrate can be determined according to the respective contact configuration to be engaged. An object of the present invention is to provide a high-performance rotary encoder which is made as small as possible and does not become too large.

Embodiment A rotary encoder according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side sectional view, and FIG. 2 is a plan view of the rotary encoder of FIG.
4 is a plan view of the fixed contact substrate, and FIG. 5 is a plan view of the rotary contact plate of the outer shaft viewed from below.

In FIGS. 1 to 5, reference numeral 21 denotes a base made of a material such as zinc die-casting.
And a columnar support shaft 24 extends vertically upward from the center of the disk-shaped bottom portion 23. A small cylindrical inner operating shaft 25 is rotatably fitted to and supported by the cylindrical support shaft 24.In order to reduce an increase in rotational torque due to the fitting portion, the cylindrical support shaft 24 is The root 24 'has a slightly larger diameter, and then a slightly smaller diameter up to the tip 24 ". The inner diameter of the small cylindrical inner operation shaft 25 has a slightly smaller diameter at only the upper end 25' and a slightly larger diameter up to the lower end 25". The upper and lower ends are point-fitted with each other, and the middle part of the fit forms a small gap to serve as a fitting grease reservoir.

Near the lower end of the outer periphery of the small cylindrical inner operation shaft 25, an inner rotating contact plate 28 made of an insulating material having a radial inner rotating contact 27 on the upper surface is rotated by a dowel 26 'of the flange portion 26 so as to rotate together. Installed.

Reference numeral 29 denotes a fixed contact substrate made of a molded resin whose outer periphery is held by a cylindrical outer peripheral wall 44 of the base portion 21. The lower elastic contact 32 electrically connected to the external lead-out terminals 30, 31 by insert-molding an elastic metal thin plate. , 33 and terminals 34, 35 are formed with upper surface elastic contacts 36, 37, which project downward and upward.

The lower elastic contacts 32 and 33 are connected to the inner rotating contact plate 2.
8 contacts the radial inner rotating contact 27 provided on
A pulse signal is issued between 0 and 31.

Also, a large cylindrical outer operation shaft 38 made of molding resin concentrically arranged outside the small cylindrical inner operation shaft 25 has its lower cylindrical portion 39 formed by the center circular hole 40 of the fixed contact board 29. It is rotatably fitted and held, but at a certain interval so that it does not rotate together with the inner operation shaft 25. And
A disk-shaped outer rotating contact plate 41 is provided on the outer periphery of the lower portion of the outer operation shaft 38.
Are formed integrally, and have outer rotating contacts 42 and 42 'on the lower surface thereof. The outer rotating contacts 42, 42 'and the upper surface elastic contacts 36, 37 projecting upward from the fixed contact board 29 come into contact with each other to generate a switching signal between the terminals 34, 35.

Further, reference numeral 43 denotes a cover made of a metal plate, which is fixed to the base portion 21 by an outer peripheral claw portion (not shown). To prevent the external operation shaft 38 from coming off upward.

The lower end of the lower cylindrical portion 39 of the outer operation shaft 38 is connected to the inner operation shaft flange portion 26 when the inner operation shaft 25 is pulled upward.
, Restricts the upward movement of the inner operation shaft 25.

The present invention is configured as described above. An inner operation knob 45 and an outer operation knob 46 are attached to the small cylindrical inner operation shaft 25 and the large cylindrical outer operation shaft 38, respectively. By rotating the external operation shaft 38 via 46, a video tape fast-forward mode switching signal is generated between the external rotating contacts 42, 42 'and the fixed elastic contacts 36, 37, and the terminals 34, 35
By rotating the inner operation shaft 25 via the inner operation knob 45, a pulse signal is generated between the inner rotation contact 27 and the fixed elastic contacts 32, 33, and a video frame feed signal is generated. It can be taken out between the terminals 30 and 31.

In the above embodiment, the fixed contacts 36, 37 and 32, 33 arranged above and below the fixed contact board 29 are elastic contacts, and the rotating contacts 42, 42 ', and 27 that come into contact with them are flat sliding contacts. However, it is a matter of course that the same effect can be obtained even if one or both of them are arranged in the reverse arrangement and the rotary elastic contact is used, and in the above embodiment, both the encoders of the outer and inner operation shafts are contact type. Although the case of a rotary encoder has been shown, it is needless to say that the same effect can be obtained even if one or both of them are optical rotary encoders and fall within the scope of the present invention.

Effects of the Invention As described above, the present invention provides: (1) a cylindrical support having a base portion disposed at the lowermost stage of a rotary encoder, a fixed contact substrate disposed above the base portion, and an inner operation shaft extending upward from the bottom surface of the base portion. The shaft is directly fitted and supported, and the outer operating shaft is fitted and held in the center round hole of the contact board. Therefore, the frequently used inner operating shaft has only one fitting gap, and the radial play is small. Become.

In addition, since the inner operation shaft and the outer operation shaft are fitted and held by separate means, the inner and outer operation shafts may rotate together even if the fitting gap is reduced in order to reduce the backlash in the radial direction. There is no.

(2) Since the rotating contact plates of the inner and outer operating shafts are arranged separately on the lower surface and the upper surface of the fixed contact substrate, the outer diameter of the contact substrate is one pair each of which engages on the upper surface or the lower surface. Since it can be determined according to the size of the contact configuration, it does not become too large.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a two-axis rotary encoder according to an embodiment of the present invention, FIG. 2 is a plan view of the embodiment without a knob attached thereto, and FIG. FIG. 4 is a plan view of the fixed contact substrate, FIG.
FIG. 6 is a plan view of a rotary contact plate of the external operation shaft, FIG. 6 is a sectional side view of a conventional two-axis rotary encoder, and FIG. 7 is a plan view of a fixed contact of the conventional example. 21 ... base part, 24 ... cylindrical support shaft, 25 ... internal operation shaft,
27 ... internal rotating contact, 28 ... internal rotating contact plate, 29 ... fixed contact board, 38 ... external operating shaft, 41 ... cylindrical rotating contact, 42 ...
… External rotating contact.

Claims (4)

(57) [Claims] 1. A disk-shaped base portion located at the lowermost stage and having a columnar support shaft extending vertically upward at the center, and a rotary contact plate at a lower end portion rotatably fitted and held by the support shaft. The held inner operating shaft, the outer operating shaft concentrically arranged outside the inner operating shaft and holding the rotating contact plate at the lower outer periphery, and the base member outer peripheral wall at an intermediate position between the outer rotating contact plate and the inner rotating contact plate. A two-axis rotary encoder comprising: a fixed contact board having fixed contacts, which are fixed to upper and lower surfaces to engage with rotating contacts of the outer and inner operating shafts to generate switching signals, respectively. 2. An outer operating shaft is rotatably fitted and supported by a round hole provided in the center of the contact board concentrically with the inner operating shaft, and an outer rotating contact plate of the outer operating shaft is suppressed by an upper surface cover. The two-axis rotary encoder according to claim 1, wherein the two-axis rotary encoder is prevented from coming off. 3. The two-shaft according to claim 1, wherein the inner rotating contact plate at the lower end of the inner operating shaft contacts the lower end of the outer operating shaft to restrict upward movement of the inner operating shaft. Rotary encoder. 4. The two-axis rotary encoder according to claim 1, wherein the fixed contacts disposed on the upper and lower surfaces of the contact board are elastic contacts protruding upward and downward, respectively.