JPS5872490A - Printer - Google Patents

Abstract

PURPOSE:To exactly perform printing in proper places by a method in which when a carriage goes back to near its starting position, a rack raker is sent to a place where a raking tooth can couple with a rack returning tooth. CONSTITUTION:When a hammer carrying cam holder 19 is separated from a rack raker 35 and moves toward the direction of arrow B (upper digit direction), the rack raker 35 is also pushed toward the direction of arrow B by the recovery force of a press spring 39, but it can not advance toward the direction of upper figure because the outer edge of a rack stopper tube 36 is catched by a rack tooth 22 on the most left end. As the rack raking tooth 35 moves, the coupling between the raking tooth 37 and the rack returning tooth 40 is released, and the raking tooth 37 is in the face of the non-toothed part between the rack tooth 22 on the most left end and the rack returning tooth 40. Thus, even when the rack raker 35 turns with a print carrying shaft 4, no collision against the rack 5 occurs and therefore, the carrying operation can be performed properly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing device, particularly a serial printer, and an object of the present invention is to provide a printing device that can accurately print in a proper position.

Recent calculators have become more multifunctional and sophisticated, and there are many types of input keys, such as scientific calculators and program calculators. Therefore, as a printing device built into this type of calculator, it is desired to develop a printing device that is capable of alpha-anime-meric printing and, since the printed data is clear, can perform this with irregular printing.

The present invention has been made in view of these points, and examples will be described below with reference to the drawings.

FIG. 1 is a diagram for explaining the schematic configuration of a printing device. Between the side plates la and lb, which are part of the frame of the printing device, there is a type wheel selection camshaft 2. Type axis 3. Print/carry shafts 4° racks 5 are sequentially installed at predetermined intervals with rotating lights NK, and although not shown, a paper feed shaft is rotatably installed below the print/carry shafts 40. .

The carriage 7, which is passed between the type wheel selection cam shaft 2 and the type shaft 30, is held slidably along these axial directions, and is moved to the home position (starting position) near the side plate 1a by a carriage return spring 8. ) What is always elastically biased. Inside this carriage 7, a slider frame 11 extending Km between the type wheel selection camshaft 2 and the type shaft 30 is placed in the carriage 7.
Similarly, it is arranged to be slidable in the axial direction. In the slider frame 11, a type wheel group 1O consisting of four type wheels 91 to 9d spline-coupled to the type shaft 3 and a type wheel selection cam 12 spline-coupled to the type wheel selection cam shaft 2 are held. ing. Carriage 7 and slider frame 11
Type ring group return spring 13 loosely fitted to type shaft 3 between
As a result, the type wheel group 10 and the type wheel selection cam 12 are always pushed toward the reference position on the side plate 11' side via the slider frame 11.

The type wheel selection cam 12 is connected to the type wheel selection cam shaft 2 as described above.
Since the type wheel selection cam 12 is spline-coupled, it can rotate integrally with the shaft 2 and slide along the axial direction, and a cam groove 14 is formed on the outer periphery of the type wheel selection cam 12. Although not shown, the cam groove 14 is composed of a deformed spiral sending cam groove and a return cam groove bent in the middle.
Both cam grooves are in communication, and the feed cam groove extends over 374 degrees (09 to 270°) K in the circumferential direction of the type wheel selection cam 120, while the return cam groove extends over 174 degrees K in the circumferential direction of the type wheel selection cam 12. ' (270° to 360') K.

As shown in FIG. 1, the cam groove 14 of the type wheel selection cam 12
A protrusion 15 is provided on the carriage 7, and when the type wheel selection cam 12 is rotated, the guide of the protrusion 15 and the pressing force of the type ring group return spring 13 work together to select the type ring group 10 and the type wheel selection. Slider frame 11 holding cam 12
moves back and forth in the left and right direction within the carriage 7.

That is, in the initial state, the type ring group return spring 13
The slider frame 11 is pushed to the leftmost position 11 of the carriage 7 by the pressing force, and the protrusion 15 engages with the cam groove 14 at a position on the tip end side of the feed cam groove. In this state, the first
The th type ring 9a is connected to the hammer 16 in the hammer/carry cam holder 19 supported by the print/carry shaft 4 and the paper 17.
are facing each other through. The position where the first type ring 9a faces the hammer 16 in this manner is referred to as the reference position of the type ring group 10 (see FIG. 1).

Next, when the type wheel selection cam 12 is rotated 9Q' in a predetermined direction by the type wheel selection cam shaft 2, the slider frame 1 is guided by the protrusion 150 fixed to the type wheel selection cam 12.
1 is shifted by a predetermined amount to the right in FIG. 1 while compressing the type ring group return spring 13, and the second type ring 9b now faces the hammer 16. Furthermore, when the type wheel selection cam 12 is rotated 90' and 11 in the same direction, the type wheel group 10 and the slider frame 1 are selected as described above! , type selection cam 12
is entirely shifted to the right by a predetermined amount, and the third type wheel 9 faces the hammer 16. Further, by rotating the type wheel selection cam 12 in the same direction K 90c', that is, by rotating the type wheel selection cam 12 2700 times from the start of rotation, the type wheel group 10 is shifted to the fourth type wheel. 9d can be opposed to the hammer 16.

Such feeding of the type wheel group lO is performed while the protrusion 15 is sliding in the feed cam groove of the type wheel selection cam 12, and therefore it is difficult to decide which type wheel 9 should face the hammer 16. can be selected by adjusting the rotation angle of the type wheel selection cam 12 (type wheel selection cam shaft 2).

When the fourth type shaft 9d is facing the hammer 16 and the type wheel selection cam 12 is further rotated in the same direction, the center portion 15 moves from the feed cam groove to the return cam groove. Since the direction of the return cam groove is opposite to the feed cam groove, by successively rotating the type wheel selection cam 12 by 90 degrees in the same direction, the protrusion 1! s returns to the tip of the feed cam groove. That is, since the protrusion 15 slides in the return cam groove, the type wheel group 10, the slider frame 11, and the type wheel selection cam 12
The assembly with returns, and the first type shaft 9a hangs! 16 again. Since the type wheel selection camshaft 2 (type wheel selection cam 12) rotates only in a fixed direction, the feeding and return of the type wheel group 10 are repeated alternately, and the type wheel 9 is selected during this period.

As shown in FIG. 1, a type wheel position sensor 18 is fixed to the left end of the type axis selection camshaft 2, and this sensor K determines which type axis 9 is currently facing the hammer 16. A positional state is detected. Further, as shown in FIG. 1, a type position sensor 25 and a type reference position sensor 26 are fixed to the right end of the type wheel 3.

As shown in FIG. 1, a hammer O carry cam holder 19 is slidably held on the printing/carry shaft 4, and a hammer 16 and a carry cam 20 are arranged inside the hammer O carry cam holder 19. The carry cam 20 is spline-coupled to the print/carry shaft 4, and a handle ff16 is held on the side facing the type ring group 10 so as to be extrudable.

As shown in FIGS. 2, 3, and 4, the carry cam 20 has two protrusions 2X formed at an interval of 180° on its outer circumference. This protrusion 21 includes a circumferential protrusion 21m extending in the circumferential direction KW provided over approximately 1/4 of the circumferential direction of the carry cam 200, and a circumferential protrusion 21m extending approximately 1/4 of the carry cam 20 in the circumferential direction.
The protrusions 21m and 21b are continuous. The protrusions 21 of the carry cam 20 are designed to mesh with rack teeth 22 provided on the rack 5, as shown in FIG. The rack teeth 22 have a conical shape with a K1m head as shown in FIG. 5, and are arranged in rows at equal intervals along the longitudinal direction of the rack 5.

As shown in FIG. 1, the carriage 7 has six! -La 23
Rope (thread body) 2 stretched through m-23f
4, it is connected to the hammer/carry cam holder 19. Therefore, the carriage 7 is configured to move in the same direction and by the same amount in synchronization with the hammer/carry cam holder 19. As mentioned above, since the carriage 7 is always urged toward the home position 1 by the carriage return spring 8, the protrusion 21 of the carry cam 20 normally meshes with the rack tooth 22 in an elastic manner due to this influence. ing. And printing/
When the girder-lifting shaft 4 (carry-lifting cam 20) is rotated by 1/4wA in the direction of the arrow as shown in FIG.
is in sliding contact with the circumferential protrusion 21m, so the carry cam 2
There is no 0 movement, just a 1/4 rotation on the spot. When the print/carry shaft 4 (carry cam 20) is then rotated 1/4 in the direction of arrow A, the light weight circumferential protrusion 21
The next rack tooth 22K, which was still in contact with the rack tooth 220,
The spiral protrusion 21b of the other protrusion 21 comes into sliding contact, and as the carry cam 20 rotates, the carry cam 20 moves by a distance equivalent to one digit to which side plate 1b.
Move toward gRK, that is, in the direction of arrow B in FIGS. 1 and 14.

The hammer 16 is arranged together with a carry cam 20 in a holding body 19, while the carriage 7 is connected to the holding body 19 via a lobe 24.

Then, when the carry cam 20 moves in the direction of arrow B by an amount corresponding to one digit, the carriage 7 and the hammer 1
6 is also transferred by the same amount in the same direction.

As shown in FIG. 1, the rotational force of the motor 2γ, which always rotates in one direction, is applied to the type shaft 3 via the type selection clutch 28.
It is also transmitted to the type wheel selection camshaft 2 via the type wheel selection clutch 29, and further to the print/carry shaft 4 via the print/carry clutch 30, respectively. The rotation transmission between the type selection clutch 28 and the print/carry clutch 30 is switched by the first switching member 31, and the rotation transmission between the type wheel selection clutch 29 and the print/carry clutch 30 is switched by the first switching member 31. 2. The appropriateness is controlled by the switching member 32. The first switching member 31 is operated by the first electromagnet 33, the second switching member 31 is
The switching members 32 are operated by second electromagnets 34, respectively.

As shown in Figure 1, the side plate 1 is placed on the print/carry shaft 4.
A rack raising member 35 spline-coupled to the shaft 4 of K near the inner surface of a is held. This rack lifting member 35 is a cylindrical rack having an outer diameter K that can be contacted with the rack teeth 22 km as shown in FIG. Stopper pipe part 36 and its rack stopper pipe part 360 side plate 1
It has a scraping tube part 38 which is integrally provided on the island side and has one scraping tooth 37 protruding from the outer periphery. Between the rack lifting member 35 of the printing/carrying shaft 4 and the side plate 1a,
A suppression spring 39 having an elastic force smaller than the tensile force of the carriage return spring 8 is loosely fitted, and the rack lifting member 35 is always elastically biased in the direction of arrow B.

On the other hand, on the outer periphery of the end of the rack 50 closer to the side plate 1a, as shown in FIG. A return tooth 40 is provided protrudingly. Between this rack return tooth 40 and the leftmost rack tooth 22, a toothless portion is formed with an interval longer than the width of the scraping tooth 370.

Next, the operations of the rack 59, carry cam 20, rack lifting member 35, etc. of this printing device will be explained with reference to FIG.

When one line of printing is started, the carriage 7 and the hammer/carry cam holder 19 are moved by the carriage return spring 8.
Due to the tensile force of the machine, it is waiting in the home position. In this state, as shown in FIG.
ni: The pressing spring 39 has a smaller elastic force than the carriage return spring 8, so it is compressed 1! It's an IC. At this time, the rake-up tooth 37 and the rack return tooth 40 are in a trap state where they can be held together, and the print/carry shaft 4 is moved as shown in FIG. Then, the rack 5 is rotated counterclockwise by a predetermined angle 11, and the rack 5 is returned to the position where the rack teeth 22 engage with the protrusions 21 of the carry cam 20 using the raising teeth 37.

While the type to be printed is selected by the type wheel position sensor 18 and type position sensor 25 (see Fig. 1) K and sequential printing and carry operations are performed, that is, the hammer/carry cam holder 19 is Rack lifting member 3
5, the rack lifting member 35 is also pushed in the direction of arrow B by the restoring force of one pressing panel 39. However, Figure 6-)
As shown in K, the outer edge of the rack stopper tube portion 36 comes into contact with the leftmost rack tooth 22, and does not advance toward the upper digits. As the rack raising member 35 moves, the engagement between the raising teeth 3'7 and the rack return teeth 40 is released.
The scraping tooth 37 faces the toothless portion between the leftmost rack tooth 22 and the rack return tooth 40. Therefore, printing and
Even when the rack raising member 35 rotates together with the carry shaft 4, it does not collide with the rack 5, and the carry operation is properly performed.

When the carriage 7 is returned after one line of printing is completed, the rack 5. is rotated in a predetermined direction, thereby releasing the engagement between the rack tooth 22 and the protrusion 21 of the carry cam 20, and the leftmost rack tooth 22 is removed from the rack tooth horn (-tube portion 36).

The rack lifting member 35 is
is pushed toward the upper digit, and the rack stopper tube portion 36 enters the lower side of the rack tooth 220 as shown in FIG. Therefore, until the hammer/carry cam holder 19 returns to the home position 1 due to the tensile force of the carriage return spring 8, even if the rack 5 attempts to return to its original position due to vibration or the like, the rack teeth 22 will not move. The rack's horn is in contact with the circumferential surface of the pipe section 360 and cannot be returned to its original position.

This function of the rack stopper tube 36 ensures that the rack tooth 22 and the carry cam 20 are not engaged with each other, and the return of the carry cam holder 19 is not caught. It is carried out smoothly, collides with the rack lifting member 35, and returns to the home position at the same time.Even after the carriage return is completed, the rack 5 continues to be rotated, and the rack 5 is kept in a rotating state (see Fig. 6). ,
As explained in 2), the rack 5 is returned to its original position in connection with the paper feeding operation to the next line, and the rack 5 and the carry cam 20 are engaged with each other.

In order to further improve the degree of alignment of the print lines printed on the paper 17, the design is such that the play in each shaft 2, 3, 4 of the carriage 7, type ring group 109, carry cam 20, etc. is minimized. Therefore, for example, when the printing device is used at low temperatures, the carriage 7, the type ring group 10. The return of the raising cam 20, etc. is difficult, and the carriage return operation takes time.

If the rack 5 is returned to its original position before the carriage return is completed, the carry cam 20 will get caught in the middle of the rack 5, and the printing position on the paper 17 will be different. 5, a carriage that holds a type carrier and is movable in the carry direction; a rack that has a large number of rack teeth along the carry direction of the carriage and is rotatable in a predetermined direction; A carry cam that engages with the rack teeth and rotates to transport the carriage in the carry direction, and a carriage return means that returns the carriage to the starting position, are used to move the carriage to a predetermined position. When the rack is raised, the rack rotates to release the carriage from the carry cam, and the carriage is returned to the starting position by the carriage return means. A rack scraping/lifting member is installed, which has a scraping pipe part having a protruding scraping tooth that engages with the rack return tooth, and a rack stopper pipe part whose outer periphery abuts the rack tooth. When in a state other than -carriage return, K keeps the rack raising member waiting at a position where the rack return tooth and the scraper tartar do not engage, and when the rack rotates during carriage return, the rack is raised. When the engagement with the cam is released, the rack lifting member is moved to a position where the rack stopper pipe faces a part of the rack teeth to maintain the rack in the non-engagement state with respect to the carry cam, and the carriage starts. When the rack returns to the vicinity of the feeding position, the rack raising member is moved to a position where the raising teeth engage with the rack return teeth, and the action of the rack raising member rotates the rack to the position where it engages with the carry-up cam. It has become a configuration trap.

Therefore, K has plenty of time until the carriage return starts and the rack returns to its original position, and the rack does not return midway (the carriage, carry cam, etc. completely return to the home position). After that, the rack can be rotated and engaged with the carry cam, eliminating the above-mentioned problems and printing accurately at the correct position even at low temperatures.

[Brief explanation of drawings]

Figure 1 shows a printing device according to an embodiment of the present invention. Figure 1 is a schematic configuration diagram of the printing device, and Figures 2, 3, and 4 are flat views of the carry cam. , front view, five-plane development view, Figure 5 is a plan view of the rack, Figure 6 (Pi), (B), (
C), 2), (e), and (f) are operation explanatory diagrams for explaining the operation of the rack lifting member. 5... Rack, 7... Carriage, 8
...Carriage return spring, 9a-mat...
...Print ring, 10...Print ring group, 20...
...Carry cam, 21...Protrusion, 22...
... Rack teeth, 35 ... Rack edge raising member, 36 ... Rack stopper tube section, 37 ...
... Raising tooth, 38... Raising tube part, 3
9... Pressing spring, 40... Rack return tooth. ? Z Figure 76 Figure 6

Claims (1)

[Claims] A carriage that holds a type carrier and is movable in the carry direction, a rack that has a large number of rack teeth along the carry direction of the carriage and is rotatable in a predetermined direction, and the rack. A carry cam that is opposed to each other and engages with rack teeth to transport the carriage in the carry direction during rotation, and a carriage return means that returns the carriage to a starting position, and the carriage is moved to a predetermined position. When raised, the rack rotates out of engagement with the carry cam. In the printing device in which the carriage is returned to the starting position by the carriage return means, a rake tube having rack return teeth protruding from an end of the rack and rake teeth protruding to engage with the rack return teeth. A rack lifting member having a rack stopper pipe portion whose outer circumferential portion is in contact with the rack teeth is installed, and K is a position where the rack return teeth and the lifting teeth do not engage when in a state other than carriage return. The rack lifting member is kept on standby, and when the rack rotates during carriage return and is released from the carry cam, the rack is raised to a position where the rack stopper tube faces some of the rack teeth. transporting the raising member to maintain the rack in a disengaged state with respect to the raising cam;
When the carriage has returned to the vicinity of the starting position, move the rack raising member to the position where the raising teeth engage with the rack return teeth, and engage the rack with the carrying cam by the operation of the rack raising member. A printing device characterized in that it is configured to be rotated to a position where it can be rotated.