JPS5967B2 - Print selection device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a print selection device.

An object of the present invention is to reduce the number of components of a print selection device to reduce component costs. Another object of the present invention is to simplify component parts, facilitate component manufacture, and reduce assembly man-hours.

Still another object of the present invention is to reduce power consumption by shortening the energization time of the electromagnetic actuator.

Another purpose is to improve ease of assembly and maintenance services by unitizing the print selection device. Conventional print selection devices can be roughly divided into two types: a print drum impact type (hereinafter referred to as a drum type) and a type wheel selection press printing type (hereinafter referred to as a type wheel type).

The drum method performs impact printing using hammers that are arbitrarily selected and placed on a regularly rotating type drum. This system facilitates the use of an ink-impregnated ink roller brought into contact with the printing drum, and is excellent for printing devices where the length of ink life is an issue, especially printing devices for electronic registers. However, the disadvantages of this drum method are that the printing noise is loud, the printing is easily smeared and cleaning maintenance is required, and delicate timing is required for the rotation of the printing drum and the operation of the hammer, which makes assembly and maintenance difficult. Not only does this have drawbacks, but the structure of the device becomes complicated, which also affects manufacturing costs. On the other hand, the type wheel method has major advantages such as the printing noise is low, the type wheel can be easily replaced when the printed characters change, and delicate phase adjustment such as that between the print drum and hammer is not required. . However, most conventional type wheel type printing devices perform alignment printing by sequentially driving selected type wheels, and are unsuitable for use with ink rollers, so they are forced to use ink ribbons. For this reason, it is considered to be a major drawback in electronic registers that require heavy duty use. In addition, a type wheel method has been devised in which the ratchet pawl and the ratchet wheel are engaged and driven, but in order to maintain the engagement between the ratchet pawl and the ratchet wheel, the electromagnetic actuating device is kept energized until the end of printing. Not only does this method have disadvantages, such as the need to use a ratchet wheel for each type wheel, but it also has major disadvantages in terms of cost and mechanism in manufacturing and assembling parts. The present invention has been made in view of the above reasons.

This will be explained below with reference to the drawings. FIG. 1 is a sectional view of a print selection mechanism showing an example of the present invention.

In the figure, reference numeral 1 denotes a type wheel shaft, which is provided with a plurality of spline grooves 1-1 and is driven by a prime mover (not shown) to rotate any type surface 2-1 of any type wheel 2 to a predetermined printing position. As a selection process, it rotates once in the direction of the arrow. After that, it stops, and during that time the printing roller 15 rotates along the rotation trajectory 1.
5-1 to press and print on a predetermined character surface 2-1. After printing is completed, the type wheel shaft 1 is driven to rotate once again in the direction of the arrow along with the type wheel 2 which has completed the predetermined printing, and is driven to rotate once in a return stroke to return the type wheel 2 to the standby state (the state shown in the figure). ing. By making one rotation of the return stroke faster than one rotation of the selection stroke, consideration is given to providing a margin for the selection path without slowing down the entire printing cycle. The type wheel 2 has a clutch pawl 3 and a clutch spring 4 built into the other side of the plurality of type faces 2-1 on the circumference. It is biased to mesh with the Further, on the outer periphery of the clutch pawl 3 and the clutch spring 4 on the side surface of the type wheel 2, there is provided a protruding ridge (hereinafter referred to as a detent guide) 5 having a partially notched portion and a recessed portion. The clutch pawl 3 is arranged so that the head 3-1 of the clutch pawl 3 protrudes from the notch of the detent guide 5. The cutout ends 5-1 and 5-2 of the daytent guide 5 serve as contact surfaces for the clutch pawl 3 when it is activated. That is, when the clutch pawl 3 rotates to mesh with the spline groove of the type wheel shaft 1, the clutch pawl 3 is prevented from rotating at the point where the notch 5-2 and the head 3-1 of the clutch pawl 3 come into contact with each other, and the daytent guide 5 It is designed to maintain a predetermined positional relationship. Also, when the type wheel 2 returns to rotation, the head 3-1 of the clutch pawl 3 and the bent portion 81 of the trigger spring 8
contact, and the clutch pawl 3 connects to the spline structure 1- of the type wheel shaft 1.
1, the head 3-1 of the clutch pawl 3 hits the notch end 5-1 of the detent guide 5, so that the type shaft 2 does not overrun, and the detent spring 11 enters the recess of the detent guide 5. As soon as it falls down, it quickly comes to rest in a standby state (the state shown in the figure). Illustrated standby state, i.e. spline groove 1 of type wheel shaft 1
-1 and the clutch pawl 3 are disengaged, the regulating force of the detent spring 11 prevents the type wheel 2 from rotating blindly. The trigger spring 8 bends at the bent portion 8-1 due to its own elastic force.
is arranged so as to be in contact with the outer peripheral surface of the detent guide 5 of the type wheel 2 and the head 3-1 of the clutch pawl 3, and one end is screwed to the suction plate holder 9 together with the detent spring 11, and the other end is an electromagnetic actuator. The free end 6 of the suction plate 6 which is the polarizing member of
-1 is engaged. In the standby state, the bow plate 6 is held at a position apart from the iron core 7 around which the electromagnetic coil J and P of the electromagnetic actuator are wound, and when the electromagnetic coil r-1 is energized, the electromagnetic actuator is activated. Yoke 1 forming part of the magnetic path
3 to release the engagement between the bent portion 8-1 of the trigger spring 8 and the head 3-1 of the clutch pawl 3. In the figure, reference numeral 10 denotes a substrate 12 that supports the electromagnetic coil J and shaft P, and a type wheel guide 12 positions the type wheel 2 in the digit direction, and 14 is an ink roller, which adjusts the type surface and circumferential speed by the rotation of the type wheel shaft 1. The ink rollers are forced to rotate so that the circumferential speeds of the outer peripheral surfaces of the ink rollers match.

Figure 2 is a side view of Figure 1, showing the yoke 13 of the electromagnetic actuator.
A bearing portion for the type wheel shaft 1 is provided by bending and raising a part of the type wheel shaft 1. The bearing portion is designed so that the type wheel set incorporating the type wheel 2 can be attached and removed, and the entire type wheel selection device is constructed as one unit. In addition, ink roller 1
4 is also incorporated in the same way as the type wheel set, so that the whole including the ink roller 14 can be handled as a unit. In the present invention arranged in this way,
When the type wheel spindle 1 selectively rotates the type wheel 2 in response to input information, a short pulse-like signal is output to momentarily excite any electromagnetic coil J or P.

Therefore, the suction plate 6 is attracted, and the bent portion 8-1 of the rotating retrigger spring 8 is pulled away from the outer peripheral surface of the detent guide 5 by 1 distance, thereby releasing the engagement with the head 3-1 of the clutch pawl 3. As a result, the clutch pawl 3 is rotated clockwise in the figure by the biasing force of the clutch spring 4, and engages with the spline groove 1-1 of the type wheel shaft 1, so that the type wheel 2 and the type wheel shaft 1 are integrated with each other. The ring 2 comes into contact with the cutout end 5-2 of the daytent guide 5 and stops rotating. When the extremely high energization to the electromagnetic coil J and P stops, the trigger spring 8 again uses its own elastic force to separate the suction plate 6 from the iron core 7, and at the same time brings its own bent portion 8-1 onto the outer surface of the clutch pawl 3. along the outer peripheral surface of the day tent guide 5. In this way, while the type wheel set 1 rotates once from the reference position as a selection stroke, the same operation is performed on the type wheel portion of each digit, and each type wheel 2 successively rotates as one body with the type wheel set 1. start. In this manner, when one rotation of the selection process is completed and the type wheel shaft 1 comes to rest, the type characters are aligned in the portion facing the printing roller 15 in accordance with the input information. During this rest time, the printing roller 15 moves along the rotation locus 151 and performs the printing operation. When the printing operation is finished,
The type wheel shaft 1 starts rotating again with each type wheel 2.

As mentioned above, the bent portion 8-1 of the trigger spring 8 has already occupied the position where it comes into contact with the outer peripheral surface of the detent guide 5 at this point, so the head 3-1 of the clutch pawl 3, which has rotated together with the type wheel 2, Here, the bent portion 8- of the trigger spring 8-
1 and is pushed back until it reaches the notch end 5-1 of the detent guide 5. As a result, the clutch pawl 3 rotates counterclockwise in the figure, disengaging from the spline groove 1-1, and freeing the typeface 2. At the same time, the tip of the daytent spring 11 falls into the recess 5-3 of the daytent guide and the type ring 2
Due to the regulating force of the detent spring 11, the detent spring 11 quickly stops at a fixed position without moving blindly, and one predetermined cycle ends here. When each type wheel 2 is selected and rotated in one phase, it rotates once through the selection stroke and the return stroke, and all the type faces 2-1 are brought into contact with the ink roller 14, thereby being coated with ink. As described above, according to the present invention,
By providing a spline groove integrally on the type wheel shaft itself, the clutch claw can be placed as close to the center of the type wheel as possible, creating space for providing guide ridges on the outer periphery. Moreover, by making the outer circumferential surface of this guide ridge the sliding surface of the armature member (suction plate) or the member that interlocks with it (triker spring), the armature member is always in a posture of engaging with the clutch pawl. At the same time, the notched end of the guide ridge can also restrict the movement of the clutch pawl during rotation. Furthermore, by providing a daytent regulating recess in a part of this guide ridge, it has become possible to completely prevent blind movement of the type wheel in the standby state. Therefore, the signals required during one cycle of the print selection operation are only short pulse-like signals issued at the required rotational position of the type wheel shaft, and the armature member (suction) driven by this signal is sufficient. After the clutch pawl is disengaged from the clutch pawl, the trigger plate) or the member (tricker spring) that interlocks with it slides into contact with the outer circumferential surface of the guide ridge and assumes the engagement position with the clutch pawl, ensuring reliable operation. do. Furthermore, by providing the protruding ridges on the outer periphery of the clutch pawl and clutch spring, the clutch pawl and clutch spring are prevented from protruding, and a dust-proofing effect is brought about. In this way, blind movement is prevented by the day tent, and the clutch pawl and spline groove reliably engage and disengage, thereby dramatically improving reliability and saving power at the same time. Furthermore, by providing a spline groove on the type wheel shaft itself, there is no need for a ratchet wheel or the like that pairs with the type shaft, thereby simultaneously reducing the number of parts and the number of assembly steps. Furthermore, by completely integrating the print selection mechanism into an integrated unit, it not only reduces the number of steps at the manufacturing and assembly stage and eases handling, but also contributes to improving serviceability and maintainability for general users. There is something immeasurable about it. It should be noted that the shape of the spline groove and the shape of the core and armature of the electromagnetic actuator shown in the illustrated examples do not define the present invention.

[Brief explanation of the drawing]

1 is a sectional view of a type wheel selection mechanism showing an example of the present invention, and FIG. 2 is a side view thereof. 1... Type wheel shaft, 2... Type wheel, 3.
...Clutch pawl, 4...Clutch spring,
6...Suction plate, 8...Triker spring,
11... Day tent spring.

Claims (1)

[Scope of Claims] 1. A type wheel shaft having a spline groove on its surface and rotating at variable speeds including stationary, a type wheel rotatably mounted on the type wheel shaft and having type on its peripheral surface, and a type wheel on the side surface of the type wheel. A clutch pawl that is pivotally mounted, a clutch spring that acts on the type wheel and the clutch pawl and urges the clutch pawl to constantly engage with the spline groove of the type wheel shaft, a trigger spring that engages with the clutch pawl, and the trigger spring. a print selector comprising: an electromagnetic actuator that engages and operates in response to an electrical command to deselect engagement of the clutch pawl and the trigger spring; and a detent spring that regulates the rest position of the type wheel. In the device, the guide ridge has a notch portion for positioning a part of the clutch pawl and regulating rotation of the clutch pawl, and a recessed portion for engaging the detent spring and regulating the rest position of the type wheel. A print selection device characterized by being provided on the side of a type wheel. 2. The print selection device according to claim 1, wherein the guide ridge serves as a sliding guide surface for the detent spring and the trigger spring. 3. The print selection device according to claim 1, wherein a bearing portion for the type wheel shaft is integrally formed with a yoke forming a magnetic path of the electromagnetic actuating device.