JPS60201959A - Shortest bidirectional printing control device - Google Patents

Abstract

PURPOSE:To permit the shortest bidirectional printing control in a printer which has a lead screw in which the first flute and the second flute with a larger pitch exclusively for carriage return are connected in a closed loop by comparing the periods of time to be required of two moving courses in both directions to the next starting position of printing. CONSTITUTION:A lead screw 40 in which the first flute 40a for normal feeding and the second flute 40b with a larger pitch exclusively for return are connected in such a manner that these flutes are winding in mutually opposited direction and their both ends form a closed loop, is driven by a carriage motor 1 of which rotations are reversible, and the printing head 8 of a carriage 7 is moved to both ways. And, the control portion, after printing of the data for (n) line and before printing of the following line, based on the final position for the (n) line data and the starting position for the (n+1) line data, compares the periods of time to be required for printing of (n+1) line to determine whether the normal or the reversed direction would be shorter and, also, to determine which direction should be faster when a command for return is received, and controls the direction of rotation of the motor 1 in accordance with the results of the above comparison.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a printer in which a print head is conveyed in a direction perpendicular to the direction in which a recording medium is conveyed, and in particular a printer having two guide grooves whose winding directions are opposite and whose pitches are different. Prior art related to a bidirectional shortest printing control method for a printer in which a print head is transported back and forth by a lead screw formed to intersect the outer peripheral surface and connected at both ends of both guide grooves. Problem: A bidirectional printing printer is known in which printing is performed when the print head moves in both the forward and reverse directions.The head conveyance device for this known bidirectional printing printer is as follows:
A) A lead screw having a single spiral guide groove on its outer circumferential surface is rotated in forward and reverse directions by an expensive stepping motor, thereby transporting the print head back and forth at the same speed in both directions. Some such printers perform shortest printing control, but this can only be applied to printers in which the print head moves at the same speed both in the forward and backward directions, and it is difficult to increase the actual printing speed any further.

Further, the lead is formed such that a first guide groove for conveying the print head in the forward direction and a second guide groove for conveying the print head in the reverse direction intersect with each other with the winding directions reversed. Bidirectional printers using screws are also known.

Both the first and second guide grooves (・- are connected in a closed loop fK:fr at both ends, and the lead angle (r, ↑ According to such a lead screw, it is possible to transport the print head back and forth just by continuing to rotate it in a fixed direction.It is sold separately, and a C motor can be used because it is inexpensive.This printer uses a simple Just bidirectional printing is done,
The shortest printing control is not applied, so the printing speed is always constant regardless of the length of the print data of each print line.Furthermore, in a unidirectional printing printer that prints only when the print head moves in the forward direction, No I in print! ',] In order to shorten the time required for return and increase the actual printing speed 1f, it is known to use a lead screw of VC1 or less. The pitch of the guide groove is several times (for example, twice) that of the guide groove for the forward stroke, and by simply rotating the lead screw in a fixed direction at a constant speed, the head conveyance speed at return is equal to the conveyance of the forward stroke for printing. Rub L that is bigger than Hayama
As a result, the time required for the return of the print head is shortened, and the time required for one round trip of the print head to glance is shortened accordingly. However, such lead screws have only been used in unidirectional printers and have not been used in bidirectional printers. In other words, this lead screw was considered unsuitable for bidirectional printing because the head conveyance speed at the time of return was greater than the head conveyance speed of the printed card.

OBJECTS OF THE INVENTION The first object of the present invention is that two guide grooves with opposite winding directions and different pitches are formed across the outer circumferential surface vcW, and the two guide grooves are connected at both ends to form a closed loop. The objective is to achieve bidirectional printing control in the shortest possible time with a single printer using a lead screw.

The object of No. 8'1 No. 2 of the present invention is to thereby further improve the qualitative printing speed.

Embodiment The embodiment is an example in which the present invention is applied to a crosshammer top printer having a printing capacity of 980 mm per printing line, and its outline is as shown in FIG.

The printing mechanism consists of a carriage motor 1. Slit disk 2. dotse/su62 wheel train 4. Platen 5. The line feed mechanism consists of a lead cloth 11, a knee 6, a gear ridge 7, a print head 8°, a home sensor 9, etc., and a line feed motor 10.
9 wheel train 112 paper feed roller 1') a', '12 b
and a manual knob 13. central processing unit
14 CPU includes a main control section 14.degree. gear ridge motor control section 15. Print head control section 16, line feed motor control section 1
7. Counting circuit 1B, dot column extraction section 19. Comparison circuits 20a to 20d.

It is composed of a microprocessor equipped with a dot column storage circuit 20ei, and operates according to the flowcharts shown in FIGS. 9-17.

Details of the printing mechanism will be explained with reference to FIGS. 1 and 2.

In FIG. 1, side plates 21.22 are arranged in parallel at predetermined intervals, and the platen 5 and lead screw 6 are rotatably supported by the side plates 21.22. A carriage motor 1 capable of forward and reverse driving is attached to the side plate 21 to drive the motor.

The rotation of the motor j is caused by a pinion 24. which is heated to the same temperature as the motor number 126. Gear 251 Binion 26. Platen gear 27.
Teeth T4i, 28, Binion 29. The signal is transmitted to the lead screw gear 50. Teeth l-1f25 and binion 26
Fi is formed integrally with the side plate 211F4fi, and is rotatably supported by a shaft 31 standing upright. Platen tooth t4i-
27 is fixedly slid on the protruding end of the shaft 32 of the platen 5. The gear 28 and the pinion 29 are integrally formed, and the side plate 2
1, which is rotatably supported on a shaft 65, which is erected in
The lead screw gear 30 is one of the lead screws 6.
The protruding end of llll 34 is located in the same state.

In FIGS. 1 and 2, above the lead screw 6, the carriage 7 is installed between the side plates 21 and 22 by π.
, are slidably received by guide shafts 35, 36.

The print head 8 is mounted on a carriage 7f via a head number board 37.

The printing head B&:t,'tN has a magnetically actuated printing hammer 38 and faces the platen 5. Platen 5
is provided with a plurality of (18 in this embodiment) raised portions 39 at equal angular intervals on its outer peripheral surface, and these raised portions 39J
It extends parallel to the axial direction of the ri platen 5. A spiral guide groove 40 is formed on the outer peripheral surface of the lead screw 6, and a retaining part brain 41 that hangs down from the lower surface of the carriage 7 is engaged with this guide groove 40.

The guide value 40 consists of a first groove 40a and a second groove 40t+, and the first groove 40a and the second groove 40. bFi, the winding directions are opposite to each other and they intersect, and both ends are MIS40C.
, 40d are connected to form a closed loop.

The second groove 40b has a larger pitch than the first groove 4Oa, and in this embodiment, the pitch is set at a ratio of 6:1. Therefore, the carriage 7 is transported left and right by the rotation of the lead screw B, but when it is transported through the second groove 40b, it is transported at three times the speed when it is transported through the first groove 40alC. become.

Next, the line feed mechanism will be explained with reference to FIGS. 1 to 3. The line feed motor 10 is mounted on a side plate 22 as shown in FIG. The rotation is caused by the motor binion 42. as shown in FIG. The tooth rlG43 is transmitted to the line feed gear 45 via the pinion 44 integrated with the gear 43, thereby driving the paper feed shaft 46. The rotation of the gear 45 is controlled by the line feed gear 41 via the gear 47 and the idler 4B, which are integrated with the gear 45.
C is transmitted, thereby driving the line feed shaft 50.

The manual knob 16 is equipped with a line feed shaft 46vc.

As shown in FIG. 2, the line feed shafts 46 and 50 are located below and above the platen 5, and line feed rollers 12a and 12a are respectively located below and above the platen 5.
, 12b is sympathized with. Reference numerals 51 and 52 denote guide plates, and the recording medium 54 inserted through the insertion port 53 passes through the path of the kite & 51, 52 +n and reaches the platen 5.
and 1LIJVC of the print head 8, and is ejected from the ejection opening 55a of the cover 55 covering the upper part of the printer machine body. 56.57 is written @medium 54 by line feed roller 12
This is a pinch roller for pressing against a and 12b. 56 pinch rollers are rotatably supported through a leaf spring 58 attached to the lower surface of the guide plate 52.
7 is rotatably supported within a notch 55b in the front wall of the cover 55.

In Fig. 2, two legs 7a, 7a are formed integrally with the gear 11 and the joint 7, and both legs 7a, 7a are formed integrally with the gear 11 and the joint 7.
A permanent magnet 59 is fixed between them. Below that, a home sensor (in this embodiment, a single reed switch is used) 9 is mounted on a circuit board 60. As shown in FIG. 1, the home sensor 9 is located near the left side '&22, and is used to detect whether the carriage 7 is at the home position at the left end. Furthermore, the slit disk 2 that cooperates with the dot sensor 6 has a hyperactive slit 2a formed on its outer periphery, as shown in FIG. In this example, 38 slits 2
a, ~2a8. are formed at intervals of 360°/40=9°, and the slits 2a8. There is an interval between and 2a corresponding to two slits. Therefore, as the slit disk 2 rotates, the dot sensor 3 generates a print timing pulse (FIG. 915) for operating the print hammer 3B in synchronization with the raised portion 390 tw of the platen 5. FIG. 6 shows the opposing relationship between the raised portion 39 of the platen 5 and the printing hammer 68, and the pulses of the 1st to 10th, 11th to 20th, and 21st to 30th scans are as follows:
The pulse occurs when the corresponding bulge 39 is at the 61st position 10) to dY, and the pulse from 1995 to 68M occurs when the corresponding bulge 69 is at the 1σ to (8)th position. do.

In addition, in this embodiment, all the characters, symbols, etc. of the dot matrix are formed in the grid position v of 8 rows and 7 columns (including 2 columns of spaces between characters) as shown in Figure 7. 6th
Positions ■ to (8) in the figure correspond to positions (1) to <81st position 1# in Figure 7. (9) in Figure 6, the 9th occurrence at the qo1 position
．． The 1o, 19th, 20th, 29th, and 5041st pulses are not used for actual printing, but the 1st to 10th pulses, and the 11th to 20th pulses
The pulses of the scan, 21st to 60th, and 51st to 58th scans correspond to t'l and one appropriate column of the dot matrix, respectively.Here, the shortest bidirectional printing of the printer of this embodiment The control conditions will be explained below.

When printing vcIWII, bidirectional printing is performed under the following conditions.

ill In forward direction printing, the home position is detected and the printing start position fi'' is determined.However, the following (A,) control case is excluded.

+21 Reverse printing is performed after forward printing.

The printing start position is determined based on the pulse from the dot sensor. After printing in the reverse direction, be sure to return the print head to the home position.

Regarding 1ν short printing, it is faster to print in a shorter time by pausing the head movement after printing in the forward direction, waiting for the next line of data, and printing this next line of data in either the forward or reverse direction depending on the number of digits (dot column effect). Compare and judge whether the process ends and select one of the following.

(A,) Print spatula driver moves in forward direction vc and prints the next line of data in the forward direction.

(A2) Move the print head eE direction π(h) and drive the carriage motor in reverse midway to print all of the next line data in the reverse direction starting from the last digit. After printing, return the spatula 1 to the home position.

(A3) The print head of the Kerry Toscrew furnace is advanced by the first groove to the right end, and then returned to the left end home position by the second VC groove at three times the speed, and then prints the next line data in the full forward direction.

(A4) Move the print head in the reverse direction Hr1 to print the next line data in the reverse direction starting from the last digit. After printing, head returns to home position 1~ (A,) After moving the print head in the reverse direction and returning to the home position, print the next line of data in the forward direction.

Regarding the shortest return when a return command signal is received, one of the following is selected depending on the head position when printing is completed, and the head is returned to the home position 4.

(B,) After the carriage motor is stopped once, it is driven to rotate continuously, and the head is returned to the home position by the first groove of the lead screw.

(B,) Continue rotating the carriage motor in the forward direction, and check if the lead screw is loose! Switch from the 1st groove to the 2nd groove - r Return the head to the home position at 3x speed.

Top ff! A 1 to A, the control is switched after printing one line of data, and then the last dot column r of that data.
, 'I), 4n, the number of starting dot columns Nn÷1 and the number of final dot columns Mn+ of the data in the next row, and the comparison circuits 20a and 20b of 81 to A) [Thus, the comparison is determined)1. Ru.

O4-A, control is VC selected when 'J1++)Mn+Mo+Mo'=Mn+5-5.

...Distance 1lIl that the print head overruns due to inertia after turning off the zero carriage motor 1! / ) number of dot columns (approximately 25 dot columns), and M
o'' is a constant speed [f' after restarting the carriage motor 1
To reach &-, it is a dot column ↓ father (about 10 dot columns) corresponding to the comfortable run-up distance -1.

Finally, the last dot column iter MnJ of the n-th line data that has just finished printing: the next line (n+1)th line's most locked winter dot column ηM1+1 is large (Mn+1')y
Consider the case n). In such a case, (
There are two possible cases: printing according to the n++)th line data '5CA2 control 1, and printing according to control A.

In FIG. 17, when printing of the nth line data is finished,
Immediately after that, the lightning trace to the carriage motor 1 shown in FIGS. 1 and 21-8 is cut off, or the print head 8 (carriage 7) moves approximately 2 m
Do one body dot at the position of P, which overruns five dot columns. S@ of A2 control is a quasi-11 ift for printing in the reverse direction from the last dot column on the (n+1)th row, and the carriage motor 1 is driven in the forward direction from the 13th position, thereby causing the print head 8 to move to the right. be moved towards When the printhead 8 reaches the final dot column position of the (n++)th row data, the carriage motor 1
The current is cut off, and the print head 8 stops at the P2 position, overrun by about 25 dot columns.

Then, from the 22nd position, the carriage motor 1 is rotated 11411 in the opposite direction, and the marking head 8 is moved to the left, during which time 1/fi (n
+ + ) line data will be printed.

In the case of control A, the time T(A,) to take one step to print the (n+1)th line data is the time t to move from the position P to the 22nd position 1h'', and the time t to move from the 27th position (from 〃 to P. When moving to the position (starting point of the printing area), the sum is 1lJl tt.The speed door of the print head 8 at the time of overrun after the motor body IF actually attenuates rapidly, but this is the sum of 1lJl tt. Assuming that it is the same as 118' (printing speed) [7 at the time of start-up of the motor after turning off, the +1JI at the start is very small, so if we ignore this, the travel time can be converted by the length of the travel section, that is, the number of dot columns. Therefore, the time T(Al) required for A2 control vc is as follows.

T (A2) = t+ ” tt = ((Mn+1+25) −(Ml]'+25))+(
Mn+1+25) =2Mn+l-Mn+25 On the other hand, in the case of A, control, the time required to print the (n+1)th line data iq'l T (All) is the time t3 to move from the 21st position to the stop upper position PH in the home area. and pH
When moving from the 23rd place buy to the 23rd place, it becomes the sum of ttrl t4.

T(All) = t, +t4 = ((Mn+25)+25) +(25+Mn+1) =Mn + + +Mn+75 Therefore, if T(A,)≦T(All), the fishing M
n + + 52 M n + 50 set A2
If control is selected and Mn+1>2'Mn+50 then KA
, control is selected.

Next, the field of Mn++4Mn will be considered with reference to FIG.

In the case of A, control, the time T(A,) required to print the data on the (n+1)th line is the time t required to print the data on the (n+1)th line in FIG. ,
, the time t6 required to change the guide groove from position p to position P0 n/f, the time t required to move from the 20th position to the 27th position 1c at three times the printing speed, and the time t required to change the guide groove from the position p to the P0 position n/f, and from the 27th position to the 28th position It is the sum of the time required to change the guide groove to the destination, 1...t, and the time required to move from the 28th position 1 to the P0 position 1"Jlto.

It has been empirically found that in this configuration, II\1fil t4, t6 corresponds to the time for printing 35 dot columns using 8 printing heads.

T(A,)-=t, +t, +t7+t8+t.

=(560-(Mn+25))+35+560/3 +
55 +Mn+1=Mn+l-Mn+792 On the other hand, in the case of A4 control, P in FIG.

P from the position. When moving in the opposite direction to the position 1...t,. -1
j(, 1 when printing the (n+1)th line data
ulT (A4) becomes O T (A, ) = Mn+25 Therefore, when T (A, ') < T (A4 ), that is, 2 Mn - Mn + 1) 767, A,
When control is selected and 2Mn-Mn+1≦767, A4
Control is selected.

When receiving the return command signal, go to printing using either B, control or B'2 control.
Returned to ゛.

A comparison between B1 control and B, control is as shown in Fig. 19.
P from the position PIO of the final dot column of the final data. Compare the time taken to return to the position.

The time 'r (Bl) required for return in the case of B1 control is 1...t when moving from the PIG position to the pH position.
ll and P1212 position P. Time to weigh into position ti
It becomes the sum of t.

T (B, ) = t, , + t, 2 = 25 + (Mn
+25) =Mn+50 In the case of B, control, the carriage motor 1 continues to rotate forward without stopping even after printing the final data, and returns the print head 8 i P0 position. After the print head 8 exits the P0 position, it returns to P. The time it takes to make one revolution and return to the position is constant regardless of the number of digits to be printed, and in this embodiment, it is equivalent to the time it takes to print 768 dot columns in terms of the number of dot columns. Therefore, after passing the P1o18 position, P
. The time 'r(Bt) to return to the bid becomes T(B, )==768-Mn.

Therefore, when T(Bl)<T(B,), the switching is 1,
When Q n (5,59, B1 control is selected, and when Mn is 359, B2 control is selected.B1 control, and B1
The 359 dot column, which is the branching point of control, is the 52nd digit, and when the final data is less than 52 digits, the horse control is used, and when it is 52f'/i or more, the B2 control is used to return the print head 8 to the home adhesion. It will be done.

Next, when the data in FIG. 20 is printed at F/4-second 11, the operation of A will be explained in detail.

According to the flow in Figure 9, first count circuit 1 in Figure 8.
8. Dot column calculation unit 19. Comparison circuits 20a to 20d
, dot column storage circuit 20e, etc. are used to calculate the amount of paddy. Data D sent from a terminal computer (see figure 11) etc. is bitten into a data buffer (size not shown) in the main control unit 14, and a dot color corresponding to the last digit of this data is stored. j, Mn are dot column storage circuits 20
It is stored in θ. Upon receiving the print command signal, the main control unit 1
4 causes the carriage motor control section to generate a forward rotation signal a, and the carriage motor 1 rotates in the forward direction IB. As the carriage motor 1 rotates, the slit disk 2 rotates, and the dot sensor 3 begins to generate a pulse 41 as shown in FIG. 5, and the cutting elite screw 6 also rotates in the forward direction. In the initial state, the carriage 7° is at the home position f at the left end in Figure 1, but if it is not at the home position, the carriage 7
The following operations are awaited until it returns to the home position p7.

If the carriage 7 is at the home position t; pvc, after the carriage 7 escapes from the home position 1t, the output of the 7F rehoming sensor 9 is turned off and data D1 is printed later. In this printing operation, the print size aperture mark 38 of the print head 8 is adjusted by the print head controller 1 in synchronization with the position of the first axle starting portion 39 of the platen 5 by the output pulse of the dot sensor 3.
Controlled through all 6 channels. In this printing operation, the carriage 7 is conveyed to the right by the first groove 40a of the lead screw 6 at a speed V as shown in FIG. 1 is counted up by the counting circuit 18, and 2 is placed in the dot column corresponding to the character digit marked.
is the number of counts, calculate the dot column based on 5<++
19 K is calculated sequentially.

If you want to continue printing the next line of data D after the printing of data D1 is finished, the return command signal will not reach the print control 1d.
, proceed to the flowchart in FIG. 12. The drive of the gear ridge motor 1 is stopped 1, and a line feed is performed at that jfi'l. In other words, in FIG.
, the line feed rollers 12a and 12b are driven five times via the wheel train 4. As shown in FIG. 3, the wheel train 4 includes a motor pinion 42. Gear 45. Binion 44, line feed gear 45. gear 4
7. It consists of an idler 48 and a line feed gear 49, and this -
By WA@ing the 21171st line feed rollers 12a and 12b through the column, the recording medium 54 is line fed by a predetermined distance. After this line break, the next line of data D2 is written to the data buffer VC in the main system Ibe 14, and this data D
.

The dot column Nn++ corresponding to the start digit and the dot column M1+1 corresponding to the last digit are stored in the dot column storage circuit 2.
It is stored at 0θ. Upon receiving the print command signal, the comparison circuit 20a shown in Fig. 2-78 immediately reads the data D in line C111.
, Nn++ based on the last dot column Mn and the start dot column Nn+1 of the data D2 to be printed from now on.
>Mn+65. In the example of data D, D2 of the 201st cell 1, Nn++>Mn+3s
Therefore, print ft1ll H' /d W Proceed to the flow shown in Figure 13. Carriage motor 1 moves in the forward direction again (
As a result, the gear 11 gear 7 is driven by the first groove 408 of the lead screw 6 at a speed V as shown in FIG.
At the same time, the counting circuit 18 of Figure 8 continues to count up the pulses from the dot cell. While the carriage 7 is being conveyed to the right, the print head 8 cooperates with the tri-platen 5 to print the entire data D2.

When the printing of data D is finished and you want to continue printing the next line of data D, return command (No. m has not arrived and data D,
The final dot column Mn-z is stored as Mn in the dot column storage circuit 20e of FIG. Then, the print control returns to the flow shown in FIG. 12. Same as above, 1c, temporary body 1t of carriage motor 1, data D of line feed secondary line
3 input, 14r4 start dot column N of this data D3
``' +m end dot column M1+I is newly stored in the dot column storage circuit 20e in Figure 8. When the print command signal is received, the comparator circuit 20a outputs N H+4 as described above.
') M n + 55 is compared.

Data D in FIG.

In the example of D3, Nn+l (Mn+35).In this case, the comparison circuit 20b in FIG. Based on Mn++)Mn, Mn-+-+'')2Mn
+50, 2Mn-Mn+l)767. In the example of data D, ,D in FIG. 20, Mn+j
〉Mn and Mn++ (2Mn+50), the printing system #l proceeds to the flow shown in FIG. Number of dot columns K.

When Mn+lK is reached, the drive of the W-carriage motor 1 is stopped. The carriage motor 1 does not stop rotating immediately when the power supply to it is stopped, but rotates slightly due to the inertia of the rotation of the lead screw 6 or the movement of the carriage 7:I, and the print head, and the count circuit 18 The count will also advance by that amount. After the rotation of the carriage motor 10 has completely stopped, the main control 7Xlt 14 in FIG. 8 generates a reverse rotation signal to the carriage motor control section 15, so that the carriage motor 1 is rotated in the reverse direction. As a result, the lead screw 6 rotates in the opposite direction, and the carriage 7 begins to be conveyed in the opposite direction along the first groove 40a (see FIG. 1) (see FIG. 21). When the carriage motor 1 rotates in reverse, the sand count circuit 18 shown in FIG. 8 counts down every time it receives a pulse ' from the dot sensor 3. Then, when the calculated value of the dot column calculation unit 19 reaches 2 to 2 = Jyl n + j,
The print head 8 prints the data Dsk in the reverse direction starting from the last digit. When the carriage 7 returns to the home position 1a, the carriage motor 1 is stopped, and the subsequent printing control returns to the start in FIG.

The operation when printing data D4 in FIG. 20 is substantially the same as the printing operation for data D1, except for the printing whistle, so it is printed on the next line of data D5 according to the flow shown in FIG. 12. I'll explain from there. When the print command signal is received, comparison circuits 20a and 20b shown in FIG. 8 perform the same comparison as described above.

X! In the example of data D, , D, of I 701&l,
smaller than Nn++-4E (Mn+55) and 2
Since (M n - M n+1) is larger than 767, the printing control thereafter proceeds to the flow shown in Figure 16. That is, after the printing of the data D4 is completed, the carriage motor 1, which has been mounted once, is driven in the forward direction again, and the return dot column Mn+1 of the data D is re-stored as Mn in the print digit storage circuit 20e of FIG. Due to the forward rotation of the carriage motor 1, the carriage 7 is transported at a speed V in the direction of the first groove 40a of the lead screw 6 [1E], and when it reaches the right end, the carriage 7 is transferred to the first groove 40a (switched from 1 to the second groove 40b). The carriage 7 is transported in the opposite direction at a speed of 6v.As shown in the flowcharts from ① onward in Figure 9, the carriage 7tri finally returns to the VcFi home position iv (see Figure 22), but the carriage motor iFi is still in the forward direction. In order to continue driving, the groove of the lead screw 6 at the left end is switched from the second groove 40b to the first groove 40a and is transported in the forward direction at a speed V (see Figure 23).Then, the carriage 7 After the home sensor 9 detects that the vehicle has escaped from the home position, data D is printed in the same manner as described above.

Since the return command signal does not arrive after the printing of data D is completed, the printing control proceeds to the flow shown in FIG. 12 again. That is, in the same manner as described above, the carriage motor 1 is stopped, the line feed 1 is
Next row data D6 is input, and the start dot column lJn+1 and last dot column Mn+l of this data D6 are stored. Then data D.

When receiving a print command signal for , the comparison circuits 20a and 20b of FIG. 8 perform a comparison in the same manner as described above.

In the data D, , D60 example, lJn+1 is (Mn
+35), Mn+ is smaller than Mn, and (2Mn-Mn+1) is smaller than 767. Therefore, the printing control from now on is [F
] Proceeding to the subsequent flow, the reverse printing of data D6 is done in substantially the same way as the reverse printing of data D, fl (25th
(see figure), return to the start in Figure 9.

Data D is printed in substantially the same way as data D1 according to the flow shown in FIG.

After printing on the printer D, the return command signal did not arrive.
Proceed to the flow shown in Figure 71, 12. and carriage mo 1
1 pause, line feed, data D, input, start of this data D8 and final dot column Nn+1°Mn+l notation 1
．． Sand is done. When a print command signal arrives there, a comparison is made by the comparison circuits 20a and 20b of FIG. 8 in the same manner as described above. Data D? + In the example of D8, N n+
+ is smaller than (Mn+35), and Mn+1 is Mn
The field/eye is larger than 2Mn+50, and the flow proceeds to the flow shown in FIG.

That is, the carriage motor 1 is driven in the opposite direction, and the carriage screw 7 is thereby returned toward the home position by the first groove of the lead screw 6 of the eleventh column 1 (
(See Figure 24 of the Asahi). When the home position/station 9 detects that the carriage 7 has returned to the home position, the carriage motor is temporarily stopped, and the return dot column Mn+1f Mn of the data D8 is recorded as gQ81.
'2+' dot column storage circuit 20eK is stored again. Then, when the carriage motor is driven in the forward direction again and a return command signal is received to return to the flow shown in Figure 9, the criminal
1X+ comparison circuit is data D,'? :Print. After printing data D, the dot column calculation unit 1
In step 9, the dot column Q is compared to see if it is greater than or equal to 359 or less than -ζ. In the example of data D, > 359, and according to the flow of FIG. 11, 1;
・ Line breaks can be made without stopping the carriage motor.
1° is applied. The carriage motor continues its rotation.
5. By doing so, the carriage 7 is connected to the lead screw.

(Conveyed to the right by the first groove 40a of −6 at a speed V,
At the right end, the engagement of the engaging part 41 (see FIG. 2) is switched to the second groove 40b, and the second groove 401) is returned toward the home position at a speed of 3v (see FIG. 25). Even after receiving the return command signal, the counting circuit 18 in FIG.
Re, that count duck K.

The dot column number calculated by the dot column calculating section 19 based on 2 is compared with the prekit value in the comparison circuit 20d. The preset value of the comparison circuit 20d is 7300 in this embodiment. Therefore, based on the count number of the total j'91 river path 18 after the carriage 7 escapes from the home position, the dot column is calculated 1ll (19
K, t: vThe calculated dot column 4-'J is 768
When the comparison circuit 2nd is activated, the main control unit 14
The output of the forward rotation signal a from the carriage motor control unit 15 is stopped through the gear ridge motor 1, and the gear ridge motor 1 is turned off. The point where the carriage motor 1 is turned off is slightly +jiJ from the home position M, but even after the carriage motor 1 is turned off, the platen 5. Due to the inertia of the lead screw 6, carriage 7, etc., the carriage 7t moves to the left and stops when it reaches the home position @VC.

/C Honjitsu laψ11, the carriage 7 has a speed of 1ψ5v
The carriage motor 1 was turned off using the method described above in consideration of the large inertial movement required to return to the home. It is possible to do so. However, in this case, care must be taken to prevent the carriage 7 from hovering over the home position area due to inertial travel.

If the final dot column Mn is less than 359, such as data D in FIG. 20, when the return command Δ is received, the carriage 7 is returned to the home position according to the flow shown in FIG. 10. That is, the carriage motor 1 is temporarily stopped, and a line feed is performed during that time. In the line break end class, set 8, the main control VA 14 generates a reverse rotation signal b'l to the carriage snorer nitrate 1115,
Carriage motor 1 is rotated in the opposite direction. therefore? Lead screw 6 in Figure 1 rotates in the opposite direction,
The carriage 7 is returned to the left toward the home position. When the carriage 7 returns to the home position and the output of the home sensor 9 is turned on, the carriage motor 1 The person is turned off.

Note that the present invention can be similarly implemented with any serial printer, such as a wire dot type, a thermal type, or an inkjet type, which have cross-hammer toggle printing methods, and the dot column detection method can be changed accordingly. If4 is changed. Further, in the above embodiment, the dot column O was compared, but it is of course possible to perform control by comparing the number of character digits instead.

Effects of the Invention According to the present invention described above, two guide grooves with opposite winding directions and different pitches are formed to intersect with the outer peripheral surface, and the two guide grooves are connected at both ends to form a closed loop. Printers using lead screws can realize the shortest bidirectional printing system using logic seeking, thereby further improving the effective printing speed.

[Brief explanation of drawings]

The drawings relate to an embodiment of the present disclosure, and include t, >
Figure 411 is a plan view of a cross-hammer dot printer to which the present invention is applied, and Figure 82 is the number f IRI tJ-11#i! The enlarged cross-sectional view @3 is the enlarged cross-section along the 1st European + mm line 1-1, the 4th
The figure is an enlarged sectional view of a slit disk, No. 51'XIFi
, the output pulse diagram of the dot sensor, Figure 6 shows the opposing position of the printing hammer and the raised part of the platen. ! The enlarged side view of the main parts showing the first section, Figure 7 is a dot mark formed by the same printer as above.) The enlarged 2nd view, Figure 8, shows an example of the l/cross character
The structural block diagrams of the above printer, FIGS. 9 to 16, are as follows:
Flowchart diagram, Fig. 17 is an explanatory diagram for comparison of A, control and A, 匍 1, : ゛Fig. 18 is an explanatory diagram for comparison of A3 control and A4 control, @19 Figure 20 for comparison of B, control and B, control.
The figures are an explanatory diagram showing print data and its printing, an explanatory diagram showing the movement of the radar, and FIGS. 21 to 26 are speed diagrams showing the moving speed and direction of the print head. 1... Carriage motor 2... Slit disk 3... Dot sensor 6... Lead screw 7... Carriage 8...・Print head 9...Home sensor 14...Main 11 cooling section 15...Carriage motor control section 18.19.
...Print head position detection means 20θ...Storage means 20a, 20b...First comparison means 20c...Second comparison means 40a...First groove 401 of lead screw]...
Lead screw force R2 groove or more Patent applicant: Seikodai Co., Ltd. Agent, Patent attorney, Tsutomu Mogami Figure 3 Figure 5 Figure 7 Figure 9 Tae 1101 12th bar. □□□−１” (Turn around) Figure 15 Figure 16 Figure 19 Kou Subaru District Z ヱ 子 square 藺 seal palm pasha =: ko j! Direction ρ character □ Toji amount 4 DaI: Yo〉shihe・ltoba 1shikashisushi---t2 2 bays 4611 ruru △・yto′ hyperactive 2nd
1FM Figure 22 Figure 23 Figure 24 National luck l Figure 25 Figure 26 Flowers

Claims (4)

[Claims] (1) A lead screw having a spiral guide groove on its outer circumferential surface is driven by a carriage motor capable of forward and reverse rotation, and the guide grooves are shaped so that the winding direction is opposite to each other and form a closed loop at both ends. The first and second
In the printer, the pitch of the second groove dedicated to return is larger than that of the first groove, and the print head mounted on the carriage is caused to reciprocate by rotation of the lead screw. A dot sensor that generates print timing pulses for the print head, and a dot sensor that prints the final position of the nth line data and (n+1) before printing the next (n + 1)th line data after printing all the nth line data and before printing the next (n + 1)th line data. a storage means for storing a start position and a final position of the data in the row; a first comparing means for comparing whether it is faster to print the (n+1)th line in the direction of the forward/reverse force; and a first comparison means for counting the printing timing pulses. a print head position detecting means for detecting the position of the print head, and a position of the print head at the end of printing detected by the print head position detecting means when receiving a return command signal; a second comparing means for comparing whether rotating the carriage motor in the forward or reverse direction returns the print head to the home position in a shorter time; and a carriage motor control section for controlling the rotation direction of the carriage motor. A bidirectional shortest printing control device, comprising: a main control section that receives the output of the first comparison means or the second comparison means and causes the carriage motor control section to generate a forward rotation signal or a reverse rotation signal; (2) The first comparison means is composed of a pair of comparison circuits.
, one is based on the final position of the nth row data and the start position of the (n+1)th row data, and the other is based on the final position of the nth row data and the final position of the (n+1)th row data. A bidirectional shortest printing control device according to claim 1, which performs a comparison calculation; (3) In both the first and second comparison means, the bidirectional shortest printing control device described in claim 1 is performed using either the number of characters or the number of dot columns. . (4) The bidirectional shortest printing control device as set forth in claim 1, wherein the first groove and the second groove of the lead screw have a pitch ratio of 1:3.