JPS5933318B2 - serial printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a serial printer, more specifically, a type in which print data is recorded on paper by extruding type bodies on a disc-shaped type carrier that is sequentially transferred in the column direction from the surface of the type carrier. Regarding printers.

As this type of serial printer, an electronic typewriter using a petal-shaped wheel is known.

However, Puri Fern, which uses this petal-shaped wheel,
Generally, the transportation of the carriage and the rotation of the petal-shaped wheel are controlled by separate motors, and a large electromagnetic means for driving the hammer body, which necessarily needs to be mounted on the carriage, is used. Also, since it is mounted on a carriage,
In addition to requiring multiple drive sources, the carriage becomes larger,
The product as a whole was large and expensive, and was not suitable for attachment to small desktop electronic computers. The present invention has been made in view of the above points, and provides a printer having a type carrier of this type that can accommodate a relatively large number of type characters as a small and inexpensive product with a reduced driving source, and a small calculator, etc. The purpose is to provide a printer that can be easily attached to a computer.

The details of the present invention will be explained below with reference to an embodiment shown in FIGS. 1 to 4. In the figure, 1 indicates frame bodies 2A, 2B.
A type wheel shaft rotatably held in between projects a predetermined amount to the right side of the frame 2A, and a ratchet 3 is fixed to the protruding portion, and gears 4 and 5 are separately attached to the type wheel shaft 1. It is mounted so that it can rotate freely.

Reference numeral 6 denotes a first clutch means provided between the gear 4 and the ratchet 3 (i.e., the type wheel shaft 1), which controls rotational transmission between the gears 4 and 1.

□ is a second clutch means provided with a cam groove 7a on the outer periphery, and is located between the gears 4 and 5, and controls rotation transmission between the gears 4 and 5. 8 is an electromagnet that drives an operating rod 9 that controls the two clutch means 6 and 7, one end 9a of the operating rod 9 engages with the ratchet 3, and the other end 9b engages with the cam groove 7a. It has become freely possible.

When one end 9a of the operating rod 9 is engaged with the ratchet 3, the other end 9b is separated from the cam groove 7a, and conversely, when the other end 9b is engaged with the cam groove 7a,
One end 9a functions as a so-called mechanical flip-flop that separates from the ratchet 3, and when the operating rod 9 is engaged with the cam groove 7a, the gear 4 and the type wheel shaft 1 (the ratchet 3
) rotate together, and the gears 4 and 5 are in a state in which rotation cannot be transmitted.On the other hand, when the operating rod 9 is engaged with the ratchet 3, the gears 4 and 5 rotate together, and the gears 4 and 5 rotate together. Rotation cannot be transmitted to the type wheel shaft 1. (Regarding this mechanism, the applicant of this application previously filed a patent application filed in 1973.
The details are described in No. 105,673, so please refer to them if necessary. )) 10 is a DC motor that always rotates in one direction, and a gear 11 attached to its shaft 10a meshes with the gear 4, and the rotation of the motor 10 is transmitted between the type wheel shaft 1 and the gear 5 via the gear 4. is selectively transmitted.

12 is a hammer drive shaft supported between the frames 2A and 2B;
A cam 13 for driving the hammer 1 having a length spanning the printing width of one line is attached.

14 is a gear attached to the end of the hammer drive shaft 12, and meshes with a gear 16 described later.

Reference numeral 15 denotes a shift shaft with a non-circular cross section for transporting a carriage, which will be described later, which is supported between the frames 2A and 2B, and a gear 16 attached to the end meshes with the gear 5.

A rack shaft 17 is held between the frames 2A and 2B so as to be rotatable by a predetermined amount, and a rack 18 for transporting a carriage is attached thereto.

Reference numeral 19 denotes an elongated plate-shaped carriage, and the type wheel spindle 1 is inserted into a circular hole (not shown) in the mounting pieces 19a, 19a (see FIG. 3) bent downward at the intermediate portion thereof. is slidable on the type wheel shaft 1.

Reference numeral 20 denotes a first worm body held between the mounting pieces 19a, 19a (parts not shown), which is connected to the type wheel spindle 1 by a spline shaft (a configuration in which it rotates integrally with the shaft and is slidable in the axial direction). It is transported together with the carriage 19 and transmits the rotation of the type wheel shaft 1 to a type carrier to be described later.

Reference numeral 21 denotes an attached piece 19b, 1 formed integrally with the second screw and bent downward at one end of the carriage 19.
9b (see FIG. 3), it is rotatably held so as not to fall off, and is connected to the shift shaft 15 by a spline shaft.

The teeth of the rack 18 mesh with the teeth of the worm body 21 exposed at the bottom of the mounting pieces 19b, 19b. Although the toothed portion of the second worm body 21 is not shown, half of the toothed portion is formed in the circumferential direction and the remaining half of the toothed portion is formed in a spiral shape. During rotation, the spiral teeth of the worm body 21 and the teeth of the rattle 18 do not mesh with each other, and in the latter half rotation of the shift shaft 15, the spiral teeth of the worm body 21 and the teeth of the rack 18 do not mesh. The meshing worm body 21, ie, the carriage 19 holding it, is transferred by an amount equivalent to one digit. 22 is a disk-shaped type carrier, and at the end of the carriage 19 opposite to the side holding the second worm body 21,
It is held rotatably (see Figure 3).

22a is a worm gear formed in the center of the type carrier 22, which meshes with the first worm body 20.

23 is a support shaft for supporting the type carrier 22 on the carriage 19, and 24 is a screw body.

A plurality of through holes 22b are bored at equal intervals on the outer periphery of the type carrier 22.

25... is a dome-shaped elastic support member disposed so as to cover each through hole 22b..., and its peripheral portion is attached to the type carrier 22 by an appropriate means such as gluing. It's fixed.

The support member 25 is made of elastic synthetic resin, and when the type carrier 22 is made of synthetic resin, both 22 and 25 can be manufactured by integral molding by appropriately selecting the molding material. is also possible. 26...
* is a printed character fixed to the top back surface of each support member 25 (see FIG. 4), located inside the through hole 22b, and a predetermined printed symbol 26a (see FIG. 2C) is formed at the tip thereof. It has been done.

The type body 26 is made of ink-impregnated porous synthetic resin, and an ink supply member 27 inside the type body 26
(See FIG. 4) is supplied with ink. Reference numeral 25a denotes a hole bored at the top of the support member 25, through which ink can be replenished into the ink supply member.

Note that the ink impregnated into the typeface 26 can be color-coded depending on each typeface. For example, if blue is used for numerical symbols and red is used for function symbols, the printed data can be easily identified.

When the top surface of the support member 25 is pressed, the type body 26 is inserted into the through hole 22b as shown in FIG. 4b.
The desired symbol is printed by being elastically deformed so as to be pushed out by a predetermined amount from within and lightly pressing the printed symbol 26a surface of the type 26 against the paper 29 on the paper table 28. At this time, since the support member 25 is formed as a so-called snap dome, when the top of the support member 25 is pushed down by a predetermined stroke, a part of the support member 25 is instantly reversed and deformed, and the typeface 26
The surface of the printed symbol 26a is pushed out by a fixed amount from the through hole 22b and pressed lightly against the paper 29, and immediately returns to the state shown in FIG. 4a when the pressing force is removed. Therefore, even if there are slight variations in the pressing force and stroke of the hammer body 30 (described later) that presses the support member 25, the amount of movement of the type body 26 is always constant, and uniform printing data can be obtained.
Since the impact force on the paper 29 is extremely small, less noise is generated. Various shapes are possible for the support member 25 to function as a snap dome, but in this embodiment, the support member 25 is shaped as shown in FIG. 4a.
5 has a two-stage dome shape, a node 25d is provided between the upper dome 25b and the lower dome 25c, and the upper dome 25b, which has a relatively large amount of deformation, is inverted at the node 25d as a boundary. (After reversal) Upper dome 25b
The elastic force of the lower dome 25c contributes to the return of the dome 25c.

The hammer body (pushing means) 30 for pressing the support member 25 has a central portion thereof as shown in FIGS.
Mounting piece 1 bent and formed integrally with the carriage 19
It is supported by a support shaft 31 between 9c and 19c, and is constantly pressed in the direction of arrow A in FIG.

Therefore, one end 30a of the hammer body 30 is always in contact with the cam 13, and due to the high speed rotation of the cam 13, the hammer body 30 rotates in the opposite direction of arrow A against the leaf spring 32. The top of the support member 25 is momentarily pressed down by the pressing portion 30b at the end.

Here, in FIG. 1, 33 has one end connected to the carriage 19.
In addition, a coil spring for returning the carriage 19 whose other end is attached to the frame body 2B constantly pulls the carriage 19 in the right direction in FIG. By moving the rack 18 and the second worm body 21 out of engagement, the carriage 19 is quickly returned to its home position.

Also, the rack 18 is always held in the third position by a spring (not shown).
The stopper 3 is biased with rotational force in the direction of arrow B in the figure.
The second worm body 21 at the position where rotation is restricted at 4
This meshes with the shaft 12 to transport the carriage 19 and maintain the transport position of the carriage 19. Further, in FIG. 3, reference numeral 35 is an electromagnet which, when excited, attracts the attraction piece 18a of the rack 18, disengages the rack 18 from the second worm body 21, and causes the carriage 19 to return.

In the figure, numerals 36 and 37 are rollers for feeding paper. Next, the operation of the printer of this embodiment having the above-described configuration will be described below.

When the carriage 19 is at the rightmost position in FIG. 1 and is waiting to start printing one line, the rack 18 is in mesh with the second worm body 21, and the operating rod 9 of the electromagnet 8 is in the spring state. (not shown) and engages with the cam groove 7a of the second clutch means 7. Therefore, the rotation of the motor 10 is transmitted to the type wheel shaft 1 and the ratchet via the gear 4 and the first clutch means 6. It is in a state where it can be transmitted to 3.

When the motor 10 rotates in this state, the type wheel shaft 1 rotates as described above, and the first worm body 20 on the shaft 1 rotates.
The type carrier 22 is rotated via.

Then, the electromagnet 8 is operated based on the printing command, and the operating rod 9 is disengaged from the cam groove 7a of the second clutch means 7 and engaged with the ratchet 3, thereby turning the first clutch means 6 into the OFF state ( rotation transmission is disabled), and rotation transmission between the type wheel set 1 and the motor 10 is cut off. Therefore,
The type wheel shaft 1 stops, and the type carrier 22 stops at a position where the desired symbol portion faces the pressing portion 30b of the hammer body 30. Although the excitation of the electromagnet 8 for selecting the type mentioned above is temporary, when the operating rod 9 is disengaged from the cam groove 7a of the second clutch means 7, the rotation of the motor 10 is stopped via the gear 4 as described above. As the rotation of the second clutch means 7 is immediately transmitted to the second clutch means 7 and the gear 5, the operating rod 9, which is biased toward the second clutch means 7 by the spring, 7, and the second
Until the next cam groove 7a of the first clutch means 7 faces the actuating rod 9 and the actuating rod 9 is depressed, the actuating rod 9 engages with the ratchet 3 and turns the first clutch means 6 into the OFF state. At the same time, the second clutch means 7 is turned on (rotation can be transmitted). Therefore, the type carrier 22 pushes the support member 25 to which the desired type body 26 is attached to the pressing portion 3 of the hammer body 30.
0b, the rotation of the motor 10 is transmitted to the gear 5, rotates the gear 16 and the gear 14 connected to the gear 5, and rotates the hammer 1 drive shaft 12 and the shift shaft 15. Rotate synchronously.

When the hammer drive shaft 12 rotates, the protrusion 13a of the hammer 1 drive cam 13 (see FIG. 3) presses one end 30a of the hammer body 30 during the first half rotation, causing the hammer body 30 to move around the support shaft 31. Rotate counterclockwise around the center as shown in Figure 3. Therefore, the pressing part 30b of the hammer body 30 presses down the top of the support member 25, and the type body 26 attached to the back surface of the support member 25 as described above is attached to the paper 29 as shown in FIG. 4b. A desired symbol is printed at the bottom of the paper 29. During this time, the shift shaft 15 is also rotating together with the hammer 1 drive shaft 12, but as described above, the spiral toothed portion of the second worm body 21 is easily rotated during the first half rotation of the shift shaft 15. 18, and after the above-described rotation of the hammer body 30 is completed and the hammer body 30 as well as the support member 25 (type body 26) return to the state shown in FIG. In the second half of the rotation, the spiral teeth of the second worm body 21 and the rack 18 engage with each other, and the carriage 19 is moved toward the left in FIG. 1 by an amount corresponding to one digit against the coil spring 33. When the drive of the hammer body 30 and the transport of the carriage 19 for one digit are completed, in other words, when the hammer drive shaft 12 and the digit feed shaft 15 complete one rotation, the second clutch means 7 which rotates in synchronization with this is activated. After half a rotation, the cam groove 7a of the second clutch means 7 reaches a position opposite to the operating rod 9, and the operating rod 9, pressed by the spring, falls into the cam groove 7a and separates from the ratchet 3. The second clutch means 6 is turned on, and the second clutch means 7 is turned off.

Therefore, the rotation of the motor 10 is transmitted only to the type wheel shaft 1, and only the type carrier 22 returns to a rotating state. In this state, the electromagnet 8 is energized based on the printing command that follows in the same way as described above, selects type, drives the hammer body 30, and prints on the second digit from the last position.
9 is further transferred to the upper digit by one digit.

Thereafter, in the same manner, character selection, driving of the hammer body 30, and transport of the carriage 19 corresponding to one digit are performed in sequence, and printing is performed on the paper 29 sequentially from the lower digit side to the upper digit side. When printing for one digit is completed, the electromagnet 35 is energized by the carriage 19 return command, and the rack 18 is attracted and rotated (in the opposite direction of arrow B in FIG. 3) as described above. and the second worm body 21, and the carriage 19 quickly returns to the home position by the tensile force of the coil spring 33.

After the carriage 19 returns, the electromagnet 35 is de-energized and the rack 18 is again moved to the second worm body 2 by the spring.
1, and the paper is fed by a paper feed drive source (not shown), so that the printer is ready to print a new line. Thereafter, printing is performed for each line in the same manner to obtain desired print data.

In this embodiment, since the printing operation and the shift operation are always linked, a blank part is provided on the type carrier 22, and this blank part (supporting member 2
5) where the typeface 26 is not installed is the hammer body 30
The printing operation may be performed by facing the . In the figure, the number of printed characters 26 stored in the printed character carrier 22 is shown to be relatively small, 12, for convenience of illustration, but in reality, a large number of printed characters 26 are stored. Furthermore, a petal-shaped wheel having a large number of so-called type fingers can be used as the type carrier, and in this case, an even larger number of symbols can be accommodated. As described in detail above, according to the present invention, in a printer of a type in which printing is performed by extruding type bodies on a type carrier on a disc that is transferred in the digit direction from the surface of the type carrier, type selection, hammer operation, The carriage can be transferred using a single DC motor as a drive source, and since the drive source for the hammer body mounted on the carriage is not mounted on the carriage, the carriage can be made lighter and smaller.

Overall, this type of printer can reduce the overall driving source, provide a compact, lightweight, and inexpensive printer, and is suitable for attachment to a small desktop computer, as well as being able to store a relatively large number of symbols on the type carrier. without losing the benefits of

[Brief explanation of the drawing]

The drawings all show a serial printer according to an embodiment of the present invention, and FIG. 1 is a partially simplified overall plan view, and FIG. 2A is a partially simplified overall plan view.
, b, and c are respectively a top view, a front view, and a back view of the type carrier, FIG. 3 is a sectional view of a main part, and FIGS. 4A and 4b are explanatory views of the operation. 1... Type wheel shaft, 2A, 2B... Frame, 3... Ratchet, 4... Gear, 5
... Gear, 6 ... First clutch means, 7 ... Second clutch means, 7a ...
・Cam groove, 8...electromagnet, 9...operating rod, 10...motor, 11...gear,
12... Hammer drive shaft, 13... Cam, 14... Gear, 15... Digit feed shaft,
16...Gear, 17...Rack shaft, 1
8...Rack, 19...Carriage,
20...First worm body, 21...
Second worm body, 22... Type carrier, 22a
... Worm gear, 22b ... Through hole,
25... Supporting member, 26... Typeface,
27... Ink supply member, 28... Paper table, 29... Paper, 30... Hammer body, 31... Support shaft, 32... leaf spring,
33... Coil spring.

Claims (1)

[Claims] 1. A single DC motor that serves as a driving source for each operation of character selection, hammer body operation for printing, and carriage transport, a carry means for transporting the carriage in the digit direction, and a motor rotatably held in the carriage. a type wheel shaft for rotating the type carrier; a type body disposed at equal intervals on the outer periphery of the type carrier and extruded from the type carrier surface to record print data on paper; and a type body that moves together with the carriage. and a hammer body for pushing out the type, a cam means for driving the hammer body and having a length extending over the entire printing area in the digit direction, a hammer drive shaft to which the cam means is attached, and the DC motor. a first clutch means for controlling rotational transmission between the DC motor and the hammer drive shaft and the carry means; a second clutch means for controlling rotational transmission between the DC motor and the hammer drive shaft and the carry means; It is equipped with an operating rod for alternately enabling rotation transmission between the first clutch means and the second clutch means, and an electromagnet for controlling the operating rod. Activate the first
The second clutch means is switched to a state in which rotation cannot be transmitted, the rotation of the type carrier is stopped, and type selection is performed, and the second clutch means is set in a state in which rotation can be transmitted, and the hammer body is driven by the cam means and the carry device is driven by the carry means. A serial printer characterized in that carriages are transferred sequentially.