JPS609015Y2 - Typewriter printing mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a typewriter printing mechanism in which a type wheel is driven by a motor and type is selectively printed by a waist punching hammer.

Some conventional printing devices using a type wheel include a disc-shaped wheel with radially extending elastic petals and a type at the tip.In this case, the diameter of the type wheel is directly connected to the typewriter. Related to the thickness of -, there were many types of characters, so the wheel diameter became large and it was not possible to make it thinner.

As another example, as shown in FIG. 1, there is an example in which the type wheel 1 is cup-shaped, the outer periphery is wound in a comb-like manner, and two types are provided on one petal.

In Fig. 1, 2 is a motor, 3 is a hammer, 4 is a plunger type solenoid, 5 is a plunger, 6 is an up/down lever, and 7 is a jumper.

In this case, since the type wheel 1 has two types per petal, the thickness of the type wheel 2 becomes thicker, and a vertical mechanism for the type wheel is required to select two levels of type, and a hammer is required. The plunger type solenoid for driving the solenoid requires a structure as shown in FIG. 2, and has disadvantages such as being thick, complicated, and expensive.

In FIG. 2, 8 is a plunger shaft, and 9 is a coil.

The present invention aims to eliminate these drawbacks and realize a compact electric typewriter, and will be explained below with reference to the drawings, which are embodiments.

FIG. 3 is a partial plan view showing an embodiment of the present invention, and FIG. 4 is a partial sectional view.

Reference numeral 11 denotes a type wheel in which petals having one type 11a at the tip are arranged in a cup shape around the outer periphery.

In the case of a typewriter, the number of petals is 8c@ or more.

llb is the initial position detection mechanism of the type wheel 11;
1c is an arm portion.

12 is a punching hammer, 13 is a transmission lever, 14 is an electromagnetic transducer consisting of a horseshoe-shaped electromagnet and a coil, 15 is an initial position detection mechanism, 15a and 15b are contacts of the initial position detection mechanism, 16 is an ink ribbon, and 17 is a platen. , 18 is a motor.

When input is received from a typewriter keyboard (not shown), motor 18 rotates to select a type on type wheel 11.

At this time, the initial position detection mechanism 15 is in contact with the llb portion of the type wheel 11, and when the contacts 15a and 15b of the initial position detection mechanism 15 simultaneously contact the conductive member provided on the llb portion, 15a and 15b are short-circuited. Determine the initial position.

While the key is continuously pressed manually, the amount of movement from the initial position is stored in the counter memory, and the required amount of rotation is calculated and the rotation speed is increased.

If there is no key input within a certain period of time, the type wheel 11 rotates back to the initial position.

In order to increase the accuracy of the initial position, the closer the contact position is to the outer periphery, the better.

In the present invention, the contact portion 11b of the type wheel 11 is provided on the circumference, and in order to reduce the moment of inertia of the print wheel and enable high-speed rotation, the print wheel 1
A punched part is provided between the bearing part (center part) of No. 1 and the initial position detection mechanism part 11b so as to connect in an arm shape, and a punched part is also punched between the initial position detection mechanism part 11b and the outer petal part, The band-like joint part (not shown) at the lower part of the petal part and part 11b are connected by several arm-shaped parts.

The conductive member on llb does not require a special positional relationship with the arm part, but since the contact pressure can be higher at a point with higher rigidity on the printing wheel, the conductive member on llb is placed on 11b where contacts 15a and 15b of the initial position detection mechanism 15 are in contact at the same time. The conductive member position is provided near the arm portion.

The motor 18 can be a step motor, a servo motor, a DC motor, or the like.

After the type wheel 11 stops, the electromagnet 14 is energized and attracts the transmission lever 14, and the hammer 12 moves the transmission lever 13.
is driven to strike the type 11a against the platen 17 to print.

Here, since the type wheel 11 has one type on each petal, there is no need for a vertical mechanism and the type wheel can be made thinner.Although the diameter is inevitably large, the motor 17 is Further, by arranging the hammer part, the electromagnet part, and the initial position detection mechanism part within the inner periphery of the petal part of the type wheel, the size can be reduced.

Also, if the inclination angle A of the hammer with respect to the horizontal plane is large, the thickness of the typewriter will increase due to the influence of the rear end of the hammer.
When the type wheel has only one type, there is a large degree of freedom in setting the hammer angle A, and in order to make the type wheel thinner, set A to 5° or more.
By selecting the optimum value within the range of 15 degrees, it is possible to improve printing quality and legibility of printed characters.

Furthermore, the electromagnetic conversion mechanism that drives the hammer can be made thinner by using a horseshoe-shaped electromagnet and arranging it without overlapping the hammer or the like.

In addition, in order to increase the printing speed, the outer petal part, the initial position detection mechanism part, and the center part of the type wheel 11 are connected by a minimum number of arms llc, so that the type wheel 1
1. Lighter weight and lower inertia can be achieved.

A stable shape can be obtained by setting the number of arms to 2 to 8.

As mentioned above, in the present invention, the petal part of the type wheel 11 has one type, and the main printing mechanism is arranged in a plane on the inner periphery of the petal part of the type wheel 11, so that a small and thin typewriter with a simple structure can be obtained. It is extremely useful.

[Brief explanation of the drawing]

Figure 1: Partial sectional view of a conventional printing mechanism, Figure 2:
Figures: A sectional view of the plunger solenoid of a conventional printing mechanism, Figure 3: A partial plan view showing an embodiment of the present invention, Figure 4: Book FIG. 1 is a partial cross-sectional view showing an embodiment of the invention. 11... Type wheel, 12... Hammer, 14... Electromagnet, 15... Initial position detection mechanism, 18... Motor

Claims (1)

[Scope of utility model registration request] A type wheel having a plurality of flower petals each having one type at the tip arranged in a cup shape on the outer periphery, a motor for driving the type wheel, an initial position detection mechanism for detecting the initial position of the type wheel, a stamping hammer, and an electrode conversion device, a recess is formed in the bottom back surface of the type wheel, the motor is disposed in the recess, and the initial position detection mechanism, the embossing hammer, and the electromagnetic conversion device are connected to the petal group of the type wheel. A typewriter printing mechanism characterized in that it is arranged within a formed circle.