Image forming apparatus with means for maintaining constant distance between recording head and recording sheet

An image forming apparatus, with an image forming device for forming an image on a sheet, and a position restricting unit being in contact with a surface of the sheet on a side of said image forming apparatus and keeping distance between the sheet and said image forming device constant.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to an image forming apparatus for recording 
image information on a record material (sheet) or the recording apparatus 
thereof, in particular, to a recording apparatus using an ink jet 
recording system for spraying ink corresponding to a signal. 
2. Related Background Art 
Conventionally, image forming apparatus (recording apparatuses) for use as 
printers, copiers, facsimile machines, and so forth drive an energy 
generating member for a record head corresponding to image information 
received so as to record a dot pattern image on a record material such as 
a piece of paper or a plastic sheet. 
However, in addition to such an ink jet recording system, wire-dot systems, 
thermal systems, laser beam systems, and so forth are known. Next, with 
reference to FIG. 23, an ink jet recording system will be described. A 
record head 351 discharges ink on a record paper sheet P corresponding to 
image information so as to record the image on the record paper sheet P. 
The record head 351 is disposed on a carriage 352. The carriage 352 is 
connected to a lead screw 353. The lead screw 353 is rotated by a drive 
source (not shown) so as to reciprocate the carriage 352 along a guide 
shaft 354 (perpendicular to the plane of the drawing). While the carriage 
352 is moved, the record head 351 is driven so as to discharge ink on the 
record paper sheet P. 
A conveying means conveys the record paper sheet P to the record head 351. 
The conveying means has a conveying roller 355 and a pinch roller 356. The 
conveying roller 355 is disposed on the rear side of the record paper 
sheet P. The pinch roller 356 pinches the record paper sheet P along with 
the conveying roller 355. Thus, the record paper sheet P pinched by the 
conveying roller 355 and the pinch roller 356 is conveyed to a support 
table (platen) disposed at a record position. The conveying roller 355 is 
disposed on a drive side (drive force is received and thereby rotated). 
The surface of the conveying roller 355 is coated with a high frictional 
material (for example, rubber). In addition, the pinch roller 356 is 
disposed on a follower side (rotated by the conveying roller 355). The 
pinch roller 356 is for example a metal roller. Both ends of a rotating 
shaft of the pinch roller 356 are tensioned by a pair of leaf springs 357. 
Thus, the pinch roller 356 presses the conveying roller 355. 
The distance between the record head 351 and the front surface of the 
record paper sheet P is given by: 
EQU .delta.=.delta..sub.0 -t 
where .delta. is the distance (record head distance) between the record 
head 351 and the front surface of the record sheet P; and .delta..sub.0 is 
the distance between the record head 351 and the support table. Thus, the 
ink spray distance varies corresponding to t. Consequently, the position 
of the record head 351 or conveying roller 355 should be adjusted 
corresponding to the sheet thickness t. 
SUMMARY OF THE INVENTION 
An object of the present invention is to solve the problems involved in the 
above-described related art and provide a recording apparatus that can 
keep conveying amount and record head distance constant regardless of the 
type of record material. 
To accomplish the above objects, the present invention is a recording 
apparatus comprising a record means for recording image information on a 
record material, a platen for supporting the record material at a record 
position, and a conveying means for conveying the record material to the 
record means, wherein the conveying means has a pair of rotating members 
that are tensioned and brought in contact with each other, the rotating 
members being a driving rotating member and a follower rotating member, 
the driving rotating member being opposed to the record means, the 
follower rotating member being opposed to the platen. 
Since the driving rotating member is opposed to the record means and the 
follower rotating member is opposed to the platen, the axis of the driving 
rotating member is fixed and the axis of the follower rotating member is 
movable. Thus, the conveying amount and the record head distance can be 
kept constant regardless of the type of record material (such as thick 
paper, thin paper, normal paper, or plastic sheet).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
(First Embodiment) 
Next, a first embodiment according to the present invention will be 
described. 
The first embodiment is an ink jet recording apparatus that employs an ink 
jet recording system. FIG. 1 is a perspective view showing the ink jet 
recording apparatus. FIG. 2 is a side view showing the ink jet recording 
apparatus. 
With reference to FIGS. 1 and 2, the construction of the ink jet recording 
apparatus according to the first embodiment will be described section by 
section. 
(Conveying Means) 
In FIGS. 1 and 2, reference numerals 1 and 2 are a conveying roller and a 
pinch roller, respectively. The conveying roller 1 is pivoted to a frame 
of a main body of the apparatus through a bearing. Thus, the position of 
the conveying roller 1 is fixed. A gear 1a is disposed at an edge portion 
of the conveying roller 1. The gear 1a is engaged with a motor gear 3a 
connected to a conveying motor 3. By driving the rotation of the conveying 
motor 3, the rotating force thereof is transmitted to the conveying roller 
1 through the gears 3a and 1a. The conveying roller 1 is a metal roller 
with rigidity. The conveying roller 1 is made of for example stainless 
steel. A peripheral surface 1b of the conveying roller 1 is stain-finished 
by for example a honing method so that the record paper sheet can be 
smoothly conveyed by the conveying roller 1. 
Both edges of the pinch roller 2 are rotatably supported by an arm 5. The 
arm 5 extends from an arm support table 4. Thus, the pinch roller 2 
presses the conveying roller 1. The arm support table 4 also works as a 
platen 4b that supports the record paper sheet P at a record position. A 
support shaft 6 is disposed at the arm support table 4. A twisted coil 
spring 7 is fitted to the support shaft 6. One end of the twisted coil 
spring 7 is secured to the arm 5. Thus, when the support shaft 6 is 
rotated in a predetermined direction as a rotation shaft, the pinch roller 
2 is pressed to the conveying roller 1 through the arms 5. The pinch 
roller 2 is constructed of a rotation shaft and an elastic member covered 
therearound. The elastic member is made of a material that has high 
frictional characteristics such as hard rubber. 
(Record Means) 
Reference numeral 8 is a record head. The record head 8 records an ink 
image on the record paper sheet P conveyed by the conveying roller 1 and 
the pinch roller 2. In this apparatus, as a record means, there is 
employed an ink jet recording system with a record head that sprays ink to 
the record paper sheet P. The record head comprises a fine liquid spray 
orifice, a liquid passageway, an energy applying portion, and an energy 
generation means. The energy applying portion is disposed in the middle of 
the liquid passageway. The energy generation means generates liquid 
particle forming energy applied to the liquid at the energy applying 
portion. 
The record head 8 is disposed downstream (in the conveying direction of the 
sheet) of the conveying roller 1 and the pinch roller 2. The record head 8 
is opposed to the arm support table 4. The record head 8 is disposed on 
the carriage 9. The carriage 9 is connected to a lead screw 10. A screw 
gear 10a is disposed at an edge portion of the lead screw 10. The screw 
gear 10a is engaged with a motor gear 11a. The motor gear 11a is connected 
to a screw motor 11. Rotation force of the screw motor 11 is transmitted 
to the lead screw 10 through the gears 11a and 10a. 
A pin (not shown) extends from the carriage 9. The pin is fitted to a screw 
groove 10b formed on a peripheral surface of the lead screw 10. Thus, when 
the lead screw 10 is rotated by the screw motor 11, the carriage 9 is 
axially reciprocated along the guide shaft 12. The record head 8 
discharges ink in synchronization with the reciprocal operation of the 
carriage 9 so as to record information on the record paper sheet P. 
FIG. 2 is a side view showing the conveying means and the record means of 
the recording apparatus of FIG. 1. In the first embodiment, since the 
conveying roller 1 is a follower metal roller disposed on a fixed side, a 
conveying amount of the record paper sheet P by the conveying roller 1 is 
given by: 
EQU L=r.sub.0 .multidot..theta. 
where L is the conveying amount L of the record paper sheet P by the 
conveying roller; .delta..sub.0 is the distance between the record head 8 
and the front surface of the record paper sheet P; t is the thickness of 
the record paper sheet P; r.sub.0 is the radius of the conveying roller 1; 
and .theta. is the rotation angle. Thus, the conveying amount L becomes 
constant regardless of the sheet thickness t. In addition, the distance 
(record head distance) .delta..sub.0 between the record head 8 and the 
front surface of the record paper sheet P becomes constant regardless of 
the sheet thickness t. 
According to such a construction, the conveying amount of the record paper 
sheet by the conveying means and the recording distance by the record 
means can be kept constant regardless of the sheet thickness. Thus, an 
image can be recorded with constant line pitch and ink discharge distance 
regardless of the type of the record paper sheet, thereby improving image 
quality. It should be noted that the peripheral surface of the conveying 
roller 1 may be coated with an elastic material and the pinch roller 2 may 
be made of a resin material. In this case, frictional force between the 
conveying roller 1 and the record paper sheet P can be improved, thereby 
providing a more secure sheet conveying force. 
In the above-mentioned embodiment, an ink jet recording system is used as a 
record means. However, the following construction is more preferably used. 
In this construction, an electro-thermal converting element is energized 
corresponding to a record signal. With thermal energy generated by the 
electro-thermal converting element, bubbles of ink generated by membrane 
boiling method are grown and shrunk so as to spray the ink through an ink 
spray orifice. 
FIG. 3 is a sectional view showing the recording apparatus, which is 
conveying a thin paper sheet P1 and recording an image on it. On the other 
hand, FIG. 4 is a sectional view showing the recording apparatus, which is 
conveying a thick paper sheet P2 and recording an image on it. 
In these drawings, the center position of the rotation of the conveying 
roller 1, which is opposed to the record head 8, is fixed. The pinch 
roller 2 presses the paper sheet P1 or P2 to the conveying roller 1 
corresponding to the thickness thereof. The distance .delta..sub.0 between 
the record head 8 and the paper sheet P1 or P2 is kept constant regardless 
of the thickness thereof. 
In this recording apparatus, the carriage 9 is reciprocated so as to record 
an image with a predetermined length in the conveying direction on the 
paper sheet P1 or P2 that is being fixed. After the image has been 
recorded on the paper sheet P1 or P2, it is conveyed by the conveying 
roller 1 for a predetermined length (image length) and then fixed. By 
repeating these image recording steps, an image is formed on the entire 
surface of the paper sheet P1 or P2. In other embodiments that will be 
described later, an image is recorded in the same manner. 
(Second Embodiment) 
FIGS. 5 and 6 show a recording apparatus according to a second embodiment 
of the present invention. For the simplicity, in FIGS. 5 and 6, the same 
portions as FIGS. 1 to 4 are denoted by the same reference numerals and 
their description is omitted. 
In the second embodiment, a pair of conveying rollers 15 and 16 are 
disposed downstream of a record head 8. The conveying rollers 15 and 16 
work as a discharge means. After an image has been recorded on a record 
paper sheet P, it is unloaded outside the apparatus by the conveying 
rollers 15 and 16. The conveying roller 15 has radial sharp protrusions. 
In other words, the conveying roller 15 is a spur-shaped roller. 
Hereinafter, the conveying roller 15 is referred to as the spur roller 15. 
The spur roller 15 is rotated by the conveying roller 16 in such a way 
that the edges of the protrusions of the spur roller 15 are in contact 
with the record paper sheet P. Since the area that the spur roller 15 is 
in contact with the record paper sheet P is small, the amount of non-fixed 
ink that is transferred from the record paper sheet P to the spur roller 
15 is small. Thus, the record paper sheet P is scarcely stained by the ink 
transferred to the spur roller 15. 
Reference numeral 16 identifies a conveying roller. While pressing the 
record paper sheet P to the spur roller 15, the conveying roller 16 
conveys the record paper sheet P. The conveying roller 16 is rotated by a 
motor 19. Reference numeral 17 is a gear with a rotation shaft that works 
in common with the conveying roller 16. Thus, the gear 17 is rotated along 
with the conveying roller 16. The gear 17 is engaged with a gear 18. The 
gear 18 is rotated by the motor 19 through a drive transmission mechanism 
such as a belt or a gear train. Reference numeral 20 is a bell crank that 
rotatably pivots the conveying roller 16 and the gear 17. The bell crank 
20 is oscillationally supported by a shaft 20a. Reference numeral 21 is a 
tension spring. One end of the tension spring 21 is connected to the bell 
crank 20. The other end of the tension spring 21 is connected to the frame 
of the main body of the apparatus. As shown in FIG. 6, the bell crank 20 
is biased counterclockwise. The conveying roller 16 is biased by the 
tension spring 21 so that the conveying roller 16 is pressed to the spur 
roller 15 through the record paper sheet P. 
A rotation shaft 15a of the spur roller 15 is rotatably pivoted by the 
frame of the main body. The position of the rotation shaft 15a, namely the 
position of the spur roller 15, is fixed. On the other hand, the conveying 
roller 16 is movable corresponding to the thickness of the record paper 
sheet P. 
Since the positions of the conveying roller 1 and the spur roller 15, which 
are in contact with the record paper sheet P, are fixed, the distance 
.delta..sub.0 between the record head 8 and the record paper sheet P is 
always kept constant regardless of the thickness of the record paper sheet 
P. 
The outer peripheral speed of the conveying roller 16 is faster than the 
peripheral speed of the conveying roller 1. In addition, the conveying 
roller 1 has frictional characteristics where the record paper sheet P 
slips off from the peripheral surface of the conveying roller 1. Thus, the 
conveying speed of the record paper sheet P depends on the peripheral 
speed of the conveying roller 1b. Since the record paper sheet P is 
tensioned by the conveying roller 16, the record paper sheet P is plainly 
kept by the conveyer rollers 1 and 16. At this point, the record paper 
sheet P is not in contact with a platen portion 4b of the support table 4. 
Thus, the conveying amount of record material of the conveying means and 
the recording head distance of the record means can be kept constant 
regardless of the thickness of the record material. Consequently, since an 
image is recorded with a constant line pitch and a constant ink spray 
distance regardless of the type of the record material, a high image 
quality can be accomplished. 
(Third Embodiment) 
Next, a third embodiment of the present invention will be described. 
FIG. 7 is a perspective view showing an ink jet recording apparatus 
according to the third embodiment of the present invention. 
In FIG. 7, reference numeral 101 is an ink head. The ink head 101 is 
disposed on a carrier 102. The ink head 101 is moved horizontally by a 
carrier guide 104 and a lead screw 103. Reference numeral 106 is a paper 
feed motor. The paper feed motor 106 rotates a paper unload roller 110 and 
a power feed roller 108 so that their rotations are reverse to each other. 
The paper unload roller 110 is rotated through a drive shaft 107 and a 
gear 107b. On the other hand, the paper feed roller 108 is rotated through 
a pulley 107a. 
When the rollers are rotated in direction denoted by arrow A, a leading 
edge of a paper sheet S is fed to the paper unload roller 110 by a pinch 
roller 105 and a paper feed roller 108. Since the paper unload roller 110 
is rotated in the reverse direction of the paper feed roller 108, even if 
the paper sheet S is skewed, the entire leading edge of the paper sheet S 
is in contact with the paper unload roller 110. Thus, the paper sheet S is 
prevented from being skewed. Thereafter, when the paper feed motor 106 is 
reversely rotated, the paper sheet S is fed by a spur roller 113 and the 
paper unload roller 110. At this point, the paper feed roller 108 is 
reversely rotated. A belt 112 is slipped off and the pinch roller 105 is 
tensioned by a spring 109 with a supporting point of the drive shaft 107 
and an angle of relief of an arm 111. Thus, the paper feed roller 108 is 
rotated so that the paper sheet S is tensioned with a weaker rotation 
torque than the paper unload roller 110. Since the paper sheet S is fed 
without loosening, the distance between the ink head 101 and the paper 
sheet S is kept constant, thereby improving the printing accuracy. 
(Fourth Embodiment) 
FIG. 8 is a side view showing a recording apparatus according to a fourth 
embodiment of the present invention. In FIG. 8, a paper unload roller 110 
is rotated by a drive gear 107 through a speed increasing gear 111b. A 
paper feed roller 108 is rotated through a speed decreasing gear 111a in 
the same direction as the paper unload roller 110. The speed of the paper 
feed roller 108 is lower than the speed of the paper unload roller 110. 
Reference numerals 109a and 109b are tension springs. The tension of the 
tension spring 109a is lower than the tension of the tension spring 109b. 
The paper feed roller 108 works as a tension roller. Thus, the pinch 
roller 105 and the paper feed roller 108 are tensioned and the paper 
unload roller 110 and the spur roller 113 are tensioned. Consequently, the 
sheet does not get loose, thereby improving recording accuracy. 
Reference numeral 112a is an idler gear. The idler gear 112a is engaged 
with the drive gear 107 and the speed reducing gear 111a so as to transmit 
drive force. Reference numeral 112b is an idler gear that transmits drive 
force of the drive gear 107 to a speed increasing gear 111b. Reference 
numeral 120 is an oscillation arm that is oscillationally pivoted to a 
rotation shaft of the drive gear 107. The paper feed roller 108 and the 
speed reducing gear 111a are rotatably supported at an oscillation end of 
the oscillation arm 120. Reference numeral 121 is an oscillation arm that 
is oscillationally pivoted to the rotation shaft of the drive gear 107. 
The paper unload roller 110 and the speed increasing gear 111b are 
rotatably supported at an oscillation end of the oscillation arm 121. 
Reference numeral 109a is a tension spring. One end of the tension spring 
109a is connected to the oscillation arm 120. The other end of the tension 
spring 109a is connected to a frame of a main body of the apparatus so 
that the paper feed roller 108 is tensioned to the pinch roller 105. 
Likewise, reference numeral 109b is a tension spring. One end of the 
tension spring 109b is connected to the oscillation arm 121. The other end 
of the tension spring 109b is connected to the frame of the main body so 
that the paper unload roller 110 is tensioned to the pinch roller 113. 
The pinch rollers 105 and 113 are rotatably pivoted to the frame of the 
main body of the apparatus. The positions of the pinch rollers 105 and 113 
are fixed. When a thick sheet is conveyed, the paper feed roller 108 and 
the paper unload roller 110 are placed in their far positions where they 
are spaced most apart from the pinch rollers 105 and 113. Thus, the 
distance .delta..sub.0 between the front surface of the sheet and the 
record head is always kept constant. 
In the third embodiment featured in FIG. 7, instead of the belt 112, idler 
that slidably rotates may be used. A one-way clutch may be disposed 
between the pulley 107a and the gear 7b. In this case, when the leading 
edge of the paper sheet S is fed, the paper feed roller 108 may be rotated 
with strong force. When the paper feed roller 108 is used as a tension 
roller, it may be rotated with weak force. Thus, the same effect as the 
third embodiment may be obtained. 
Thus, while ink jet record operation is performed, the record material is 
held without loosening. Consequently, the distance between the ink head 
and the record material is kept constant. As a result, since the record 
material is not in contact with the ink head, print quality is improved. 
When the record material is fed, a roller of the feeding portion is 
rotated in the reverse direction of a roller of the unload portion. Thus, 
even if the record material to be fed is skewed, the leading edge of the 
record material is adjusted at the roller position of the unload portion. 
Consequently, the ink jet record operation can be stably performed. 
(Fifth Embodiment) 
Next, with reference to FIG. 9, a fifth embodiment of the present invention 
will be described. In FIG. 9, reference numeral 201 is a detachable head 
cartridge where a record head (record means) 202 is incorporated with an 
ink tank 203. Reference numeral 204 is a carriage that holds the head 
cartridge 201. Reference numeral 205 is a guide shaft that reciprocatingly 
guides and supports the carriage 204. Reference numeral 206 is a guide 
shaft that slides and guides the carriage 204 in corporation with the 
guide shaft 205. 
Reference numeral 207 is a paper feed roller (conveying roller) that 
conveys a record material 208 such as a record paper sheet. Reference 
numeral 209 is a pinch roller that presses the paper feed roller 207 
through the record material 208 so as to produce frictional conveying 
force. Reference numeral 210 is a drive shaft disposed in parallel with 
the paper feed roller 207. The drive shaft 210 is pivoted to a main body 
of the apparatus through drive shaft brackets 211 and 212. The drive shaft 
brackets 211 and 212 are disposed on both ends of the drive shaft 210. 
Both edge portions of the paper feed roller 207 are rotatably pivoted by a 
support bracket 213. The support bracket 213 is rotatably supported about 
the drive shaft 210 that works as a supporting point. 
The pinch roller 209 is rotatably supported at a fixed position of the main 
body of the apparatus. The support bracket 213 is biased to the pinch 
roller 209 by a torsion spring 214. The torsion spring 214 is disposed on 
one side of the support bracket 213. The rotation of the paper feed motor 
207 is transmitted to the shaft of the paper feed roller through gears 
216, 217, and 218 so as to drive the rotation of the paper feed roller 
207. 
A lever portion 219 is formed on one side (right side in this drawing) of 
the support bracket 213. The lever portion 219 releases the paper feed 
roller 207 from the pinch roller 209. By pushing down the lever portion 
219 in direction denoted by arrow A, the support bracket 213 is rotated in 
the direction denoted by arrow A. Thus, the paper feed roller 207 is 
separated from the pinch roller 209 against the torsion spring 214. 
The record head 202 (head cartridge 1) is provided with an electro-thermal 
converting element that generates thermal energy that is used to spray 
ink. In reality, ink is discharged from an ink spray opening corresponding 
to an ink status change (for example, generation of bubbles due to 
membrane boiling of ink by thermal energy). 
FIG. 10 is a schematic partial perspective view showing a construction of 
an ink discharge portion of the record head 202. In FIG. 10, a plurality 
of ink discharge openings 82 are formed at predetermined pitches on a 
discharge surface 81 that is spaced apart from the record material by a 
predetermined distance (for example, 0.5 to 1.5 mm). Electric-thermal 
energy converting elements (heat generating resistor elements or the like) 
85 that generate energy for spraying ink are disposed along a wall surface 
of each liquid passageway 84 that connects a common liquid chamber 83 and 
each ink discharge opening 82. In the recording apparatus shown in FIG. 7, 
the head cartridge 201 is disposed on the carriage 204 so that the ink 
discharge openings 82 are perpendicular to main scanning direction (moving 
direction) of the carriage 204. The electric-thermal energy converting 
elements 85 are driven (energized) corresponding to an image signal or a 
discharge signal. Ink in the corresponding liquid passageway 84 is 
membrane-boiled. There is an increase in pressure which causes the ink to 
be discharged from the corresponding ink discharge opening 82. 
The record heads that are described in this specification has the same 
construction as FIG. 10. 
According to the fifth embodiment, supporting members that support both 
edges of a paper feed roller 207 are incorporated as a support bracket 
213. The support bracket 213 pivots both the edges portions of the paper 
feed roller 207. In addition, a release lever portion 219 is incorporated 
with one side of the support bracket 213. Thus, the paper feed roller 207 
is immediately separated from the pinch roller 209. Consequently, a 
release operation can be securely performed. In addition, by pressing down 
the protruded lever portion 219 (namely, with a one touch operation), the 
paper feed roller 207 can be released. Moreover, no dedicated member for 
the release operation is required. Thus, the number of constructional 
members can be reduced, thereby lowering the cost. In addition, since a 
space for the dedicated member is not required, the size of the recording 
apparatus can be reduced. 
In a recording apparatus that presses a pinch roller disposed on a movable 
shaft to a paper feed roller (conveying roller), support members disposed 
at both edges of the pinch roller are incorporated as a pinch roller 
support bracket. The pinch roller support bracket pivots both the edge 
portions of the pinch roller. In addition, a release lever portion may be 
disposed on the pinch roller support bracket. In the fifth embodiment, 
while the lever portion is being pushed down, release mode takes place. 
However, with a latch mechanism, the release mode may be continued. 
FIG. 11 is a schematic perspective view showing a paper feed mechanism of a 
recording apparatus according to a sixth embodiment of the present 
invention. In this embodiment, an extension roller portion is disposed 
outside bearings disposed at both end sides of a paper feed roller. The 
extension roller portion is coaxial to the paper feed roller. The paper 
feed roller and the extension roller portion are tensioned to a pinch 
roller so that the entire width of a record material is equally tensioned. 
In the sixth embodiment, the recording apparatus is an ink jet recording 
apparatus. 
In FIG. 11, reference numeral 201 is a detachable head cartridge where a 
record head (record means) 202 is incorporated with an ink tank 203. 
Reference numeral 204 is a carriage that holds the head cartridge 201. 
Reference numeral 205 is a guide shaft that reciprocatingly guides and 
supports the carriage 204. Reference numeral 206 is a guide shaft that 
slides and guides the carriage 204 in cooperation with the guide shaft 
205. Reference numeral 221 is a paper feed roller (conveying roller) that 
conveys a record material 208 such as a record paper sheet. Reference 
numeral 222 is a pinch roller that presses the paper feed roller 207 
through the record material 208 so as to produce a frictional conveying 
force. Reference numeral 215 is a paper feed roller that drives the 
rotation of the paper feed roller 221. 
Both edge portions of the paper feed roller 221 are rotatably pivoted by 
bearing brackets 223 and 224 disposed on the recording apparatus. 
Extension roller portions 225 and 226 are disposed outside the bearings 
223 and 224 of the paper feed roller 221, respectively. The extension 
roller portions 225 and 226 rotated along with the roller 221. A plurality 
of pinch rollers 222 are coaxially disposed so as to press the paper feed 
roller 221 and the extension roller portions 225 and 226. The paper feed 
roller 221, the extension roller portions 225 and 226, and the pinch 
rollers 222 press the record material 208 so that the entire width thereof 
is equally pressed. More specifically, the bearing portions of the bearing 
brackets 223 and 224 disposed at both edges of the paper feed roller 221 
nearly match Airy points of the paper feed roller 221 and the extension 
roller portions 225 and 226 on both the edges. 
FIGS. 12 to 14 are schematic partial vertical sectional views showing 
constructions of the paper feed roller 21 and the extension roller portion 
25 of FIG. 11. FIG. 15 is a schematic sectional view taken along line 
15--15 of FIG. 14. In FIGS. 12 to 14, an extension roller portion 223 
disposed on one side of the paper feed roller 221 is shown. The 
construction of an extension roller portion 224 on the other side (right 
side) is substantially the same as the construction of the extension 
roller portion 223 on the left side. Thus, in these drawings, the 
extension roller portion 224 is denoted with parentheses. 
In a first modification shown in FIG. 12, the sectional shape of the 
protrusion portion protruding from the bearing bracket 223 (224) of the 
shaft 227 of the paper feed roller 221 is denoted by a two-dashed line. In 
other words, the protrusion portion has one flat portion. The flat portion 
prevents the protrusion portion from rotating. In addition, a center hole 
of a core member 228 of the extension roller portion 225 (226) has one 
flat portion. The extension roller portions 225 and 226 are inserted and 
fitted into the protrusion portions on both the edges of the shaft 227 in 
such a way that they do not turn. With machine screws 229 and 229, the 
extension roller portions 225 and 226 are secured. Thus, the extension 
roller portions 225 and 226 are incorporated into the paper feed roller 
221. 
In a second modification shown in FIG. 13, taper portions 230 are formed at 
protrusion portions on both edges of the shaft 227 of the paper feed 
roller 221. In addition, taper hole portions 231 are formed at edge 
portions of core members 228 of the extension roller portions 225 and 226, 
respectively. The taper hole portions 231 are fitted into the taper 
portions 230, respectively. With machine screws 229, the taper portions 
230 are secured to the taper hole portions 231, respectively. Thus, the 
extension roller portions 225 and 226 are incorporated into both edge 
portions of the paper feed roller 221. In a third modification shown in 
FIGS. 14 and 15, extension roller portions 225 and 226 are incorporatedly 
formed at both edges of a paper feed roller 221. With bearing brackets 223 
and 224, a shaft 227 is pivoted on a load support side of a pinch roller 
222. 
In FIG. 11, a plurality of pinch rollers 222 are disposed at predetermined 
pitches on the same axis. At least one of these pinch roller 222 is 
tensioned to the paper feed roller 221, or the extension roller portions 
225 and 226 in such a way that the entire width of the record material 208 
to be conveyed is equally pressed (nearly equally loaded). Practically, as 
shown in FIG. 11, the extension roller portions 225, the paper feed roller 
221, and the extension roller portion 226 are positioned so that Airy 
points of a:b:a are satisfied. 
As is evident in FIG. 11, the Airy points correspond to the paired points 
set by the distance b for supporting the beam on which the full load is 
equally disturbed so that the strain of the beam is minimized. 
In the first to third modification of the sixth embodiment shown in FIGS. 
11 to 15, bearing portions 223 and 224 of a narrow and long sheet feed 
means constructed of a paper feed roller 221 and extension roller portions 
225 and 226 are placed so that Airy points are satisfied. The tension of 
pinch rollers 222 is equally applied to the sheet feed means. Thus, the 
sheet feed means 221, 225, and 226 can be least bent, thereby providing a 
recording apparatus with high sheet feed accuracy. 
(Seventh Embodiment) 
FIG. 16 is a schematic perspective view showing a paper feed mechanism of a 
recording apparatus according to a seventh embodiment of the present 
invention. In this embodiment, a record material guide member is disposed 
adjacent to and upstream (in a conveying direction) of a record means of 
the record material. At least a contact portion of the record material 
guide member that is in contact with the record material is bake-finished 
with a material that has water repelling characteristics, a small 
frictional coefficient against the record material, and high wearing 
resistance. In this embodiment, the recording apparatus is an ink jet 
recording apparatus. 
In FIG. 16, reference numeral 201 is a detachable head cartridge where a 
record head (record means) 202 is incorporated with an ink tank 203. 
Reference numeral 204 is a carriage that holds the head cartridge 201. 
Reference numeral 205 is a guide shaft that reciprocatingly guides and 
supports the carriage 204. Reference numeral 206 is a guide shaft that 
slides and guides the carriage 204 in association with the guide shaft 
205. Reference numeral 207 is a paper feed roller (conveying roller) that 
conveys a record material 208 such as a record paper sheet. Reference 
numeral 209 is a pinch roller that presses the paper feed roller 207 
through the record material 208 so as to produce frictional conveying 
force. 
In FIG. 16, the record material 208, which is a sheet of paper, a plastic 
sheet, or the like, is conveyed in direction denoted by arrow B by the 
paper feed roller 207 and the pinch roller 209. After the record head 202 
has recorded an image on the record material 208, the record material 208 
is discharged in the direction denoted by arrow C by a paper discharge 
roller or the like. The paper feed roller 207 is oscillationally supported 
about a shaft 235 that works as a supporting point through arm portions 
233 and 234. The arm portions pivot both edge portions of the paper feed 
roller 207. 
In FIG. 16, a cap member 261 is disposed at a home position of the record 
head 202. The cap member 261 is opposed to an ink discharge opening 81 of 
the record head 202. The cap member 261 is made of an air-tight elastic 
material such as rubber. The cap member 261 is moved by a drive means (not 
shown) so as to close or open the ink discharge opening 81. When an image 
is not recorded, the head cartridge 201 is moved to the home position. At 
this point, the cap member 261 is moved forward so as to airtightly close 
the ink discharge opening 82 of the record head 202. A wiping blade 263 is 
disposed adjacent to the cap member 261. The wiping blade 263 is disposed 
on the holder 262. The wiping blade 263 is made of an elastic member such 
as silicon rubber or urethane rubber. In synchronization with the motion 
of the carriage 204, the wiping blade 263 wipes out adhered substances 
(such as ink, paper fibers, and dust) from the ink spray orifice 81 of the 
record head 202. 
FIG. 17 is a vertical sectional view in a paper feed direction of the 
recording apparatus of FIG. 16. In FIGS. 17 and 16, arm portions 233 and 
234 that pivot the paper feed roller 207 are oscillationally disposed 
about a shaft 235. The arm portions 233 and 234 are biased to the pinch 
roller 209 by a tension spring 236 (see FIG. 18). Thus, the paper feed 
roller 207 is biased to the pinch roller 209 on the fixed shaft. 
In FIG. 16, forward edge portions of the arm portions 233 and 234 are 
brought into contact with release cams 238 and 238 that are rotated by a 
release lever 237, respectively. Thus, when the release lever 237 is 
rotated in the direction denoted by arrow D, the release cams 238 and 238 
are rotated, thereby separating the paper feed roller 207 from the pinch 
rollers 209. A gear 239 is secured to one edge of the shaft portion of the 
paper feed roller 207. The paper feed roller 207 is rotated by a motor 
(not shown) through the gear 239. The carriage 204 is reciprocated by a 
carriage motor (not shown). 
In FIGS. 16 and 17, a record material guide member 240 is disposed adjacent 
to and upstream (in the conveying direction of the record material 208) of 
the record head (record means) 202. The record material guide member 240 
guides the record material 208 that is biased and pinched by the paper 
feed roller 207 and the pinch roller 209. When the forward edge portion 
(paper contact portion 241) of the record material guide member 240 is 
brought into contact with the record material 208, the record material 208 
is guided along a predetermined conveying path. In this embodiment, an 
opening 242 is formed corresponding to each of the pinch rollers 209 of 
the record material guiding member 240. Each pinch roller 209 is pivoted 
by the record material guide member 240. In FIG. 17, a paper discharge 
system is disposed downstream (in the record paper sheet conveying 
direction) of the record head 202. The paper discharge system is 
constructed of a paper discharge roller 244 and pinch rollers 245. 
Alternatively, the paper discharge system is constructed of a paper 
discharge roller 244 and spurs 246. 
FIG. 18 is an enlarged view showing portion E (an elongate circle) of FIG. 
17. In FIGS. 17 and 18, a portion including the paper contact portion 241 
of the record material guide member 240 is coated with an outer layer 243 
that has water repelling characteristics, low frictional coefficient 
against the record material 208, and high wearing resistance. This outer 
layer 243 is formed by bake-finishing for example Teflon resin. In other 
words, the paper contact portion 241 of the record material guide member 
240 and sheared and broken surfaces of the record material guide member 
240 are coated with the outer layer 243, which is made of Teflon resin and 
has water repelling characteristics, low frictional coefficient, and high 
wearing resistance. 
According to the seventh embodiment shown in FIGS. 16 to 18, since the 
sliding characteristic of a surface where the record material guide member 
240 is in contact with the record material 208 is high, the record 
material can be quietly fed. In addition, the load of the paper feed motor 
can be reduced. Thus, damage to the record material 208 can be prevented. 
Since the record material guide member 40 is free from corroding, the 
guiding function is prevented from being lowered. Moreover, when the paper 
feed roller 207 is reversely rotated, ink on the record material 208 is 
not transferred to the record material guide member 240, the record 
material 208 and the record material guide member 240 can be prevented 
from being stained by the ink. Furthermore, since the record material 208 
is neither twisted nor waved by the pinch rollers 209, the accuracies of 
the recording operation and the paper feed operation are improved. 
The surface layer 243 may be formed by bake-finishing a lubricant 
containing molybdenum disulfide instead of Teflon resin. With this 
lubricant, the same effects may be obtained. In addition, the record 
material guide member 240 may be formed of engineering plastics containing 
Teflon or the like. As a modification of the outer layer 243, when Teflon 
resin or the like is bake-finished on metal rails that support the 
carriage 204, a carriage feed mechanism that has high sliding 
characteristics, low noise, and low motor load may be provided. 
(Eighth Embodiment) 
FIG. 19 is a schematic side view showing a paper feed mechanism of a 
recording apparatus according to an eighth embodiment of the present 
invention. FIG. 20 is a schematic partial perspective view of FIG. 19. In 
FIGS. 19 and 20, a paper feed roller has a groove portion that is disposed 
between pinch rollers. A paper contact portion of an actuator of a 
detector is disposed inside the groove portion. The detector detects 
whether a record material is present or not. Thus, in this embodiment, the 
record material is detected in a paper feed direction at a record material 
contact drive portion. In this embodiment, the recording apparatus is an 
ink jet recording apparatus. 
In FIG. 19, reference numeral 201 is a detachable head cartridge where a 
record head (record means) 202 is incorporated with an ink tank 203. 
Reference numeral 204 is a carriage that reciprocatingly holds and moves 
the head cartridge 201. Reference numerals 205 and 206 are a pair of guide 
shafts that reciprocatingly guide and hold the carriage 204. In FIGS. 19 
and 20, reference numeral 207 is a paper feed roller. Reference numeral 
208 is a record material such as a record paper sheet. Reference numeral 
209 is a pinch roller that is in contact with the paper feed roller 207. 
In FIG. 19, reference numeral 247 is a pinch roller support bracket that 
pivots the pinch roller 209. Reference numeral 248 is a support shaft that 
oscillationally pivots the pinch roller support bracket 247. Reference 
numeral 249 is a pinch roller tension spring that presses the pinch roller 
209 to the paper feed roller 207 through the pinch roller support bracket 
247. In FIGS. 19 and 20, a paper feed system is disposed upstream (in a 
paper feed direction) of the record portion (opposed to the record head 
202). The paper feed system is constructed of the paper feed roller 207 
and the pinch roller 209. A paper discharge system is disposed downstream 
(in the paper feed driection) of the record portion. The paper discharge 
system is constructed of a paper discharge roller 250 and a spur 251. In 
this embodiment shown in the FIG. 19, the paper feed system (207 and 209) 
and the paper discharge system (250 and 251) are disposed relatively close 
to the record head 202. 
In the recording apparatus shown in FIG. 19, the record material 208 can be 
fed from two directions denoted by arrows F and G (or from a plurality of 
directions). In other words, the recording apparatus has a first sheet 
guide 252 and a second sheet guide 253. The first sheet guide 252 ranges 
from a first paper insert portion (not shown) to the pinch roller 209 
(record material pressing portion). The second sheet guide 253 ranges from 
a second paper insert portion (not shown) to the pinch roller 209. Thus, 
the record material 208 can be fed from the different directions denoted 
by arrows F and G. 
In FIGS. 19 and 20, the paper feed roller 207 has a groove 254 with a 
predetermined width. The groove 254 is formed on an outer periphery of the 
paper feed roller 207 and perpendicular to an axial direction thereof. A 
sheet contact portion 256 of a detection lever 255 is disposed inside the 
groove 254. The detection lever 255 detects whether or not the record 
material 208 is present. The record material detector comprises the 
detection lever 255, a tension spring 258, and a non-contact type detector 
259. The detection lever 255 is oscillationally moved about a shaft 257 
(in this embodiment, the shaft of the paper unload roller 250). The 
tension spring 258 biases the detection lever 255 to the pinch roller 229, 
thereby pressing the sheet contact portion 256 to the pinch roller 209 
through the record material 208. The detection portion 259 electrically 
detects the motion (displacement) of the detection lever 255. The 
detection portion is for example a photointerrupter. 
In the eighth embodiment shown in FIGS. 19 and 20, the contact portion of 
the detection lever 255 and the record material 208 is placed at a 
pressing portion or pinch portion of the paper feed roller 207 and the 
pinch roller 209. Thus, the record material 208 is detected at the record 
material pressing drive portion in the paper feed direction. Thus, the 
following effects can be obtained. As a first effect, since the record 
material 208 is detected at the position of the record material pressing 
drive portion, regardless of whether the record material 208 is fed from 
the direction denoted by arrow F or G, the record material can be 
accurately detected. As a second effect, since the detection lever 255 is 
brought into contact with a pinch portion where the record material 208 is 
most strongly held, the record material 208 can be securely detected. 
As a third effect, since the sheet detector is disposed between the paper 
feed roller 207 and the paper unload roller 250, the detection mechanism 
does not protrude. Thus, the recording apparatus can be compactly 
constructed. As a fourth effect, since the record material 208 is detected 
at the pinch portion, regardless of the feed direction of the record 
material 208, the record material 208 can be securely detected by one 
detector. As a fifth effect, since the record material is detected at a 
position closest to a record portion, time lag and distance lag can be 
reduced. 
In the eighth embodiment shown in FIGS. 19 and 20, when the detection 
levers 255 are disposed at a plurality of positions corresponding to the 
width of the record material 208 and the record material detectors 
including these detection levers 255 are used, these detectors can be used 
as sheet width detectors of the record material 208 as well as sheet 
detectors. In the eighth embodiment shown in these drawings, the motions 
of the detection levers 255 are detected by optical means such as 
photointerrupters. However, instead, detectors with electric contacts may 
be used. Likewise, the paper width detectors may be detectors with 
electric contacts. 
(Ninth Embodiment) 
FIG. 21 is a schematic perspective view showing a paper feed mechanism of a 
recording apparatus according to a ninth embodiment of the present 
invention. In this embodiment, a paper feed roller and a pinch roller are 
disposed so that a record material is conveyed along a record means. A 
tension portion of a pinch roller to the paper feed roller and a tension 
portion of a pinch roller to a paper discharge roller are disposed 
adjacent to the record means. A record material guide means is disposed 
adjacent to the record means. The record material guide means extends 
along main scanning direction of the record means. The record material 
guide means is opposed to the record means. The record material guide 
means also works as a hold member of the pinch roller. In this embodiment, 
the recording apparatus is an ink jet recording apparatus. 
In FIG. 21, reference numeral 201 is a detachable head cartridge where a 
record head (record means) 202 is incorporated with an ink tank 203. 
Reference numeral 204 is a carriage that holds the head cartridge 201. 
Reference numeral 205 is a guide shaft that reciprocatingly guides and 
holds the carriage 204. Reference numeral 206 is a guide shaft that slides 
and guides the carriage 204 in association with the guide shaft 205. 
Reference numeral 207 is a paper feed roller (conveying roller) that feeds 
a record material 208 such as a record paper sheet. Reference numeral 209 
is a pinch roller that presses the paper feed roller 7 through the record 
material 208 so as to produce frictionally conveying force. 
The record material 208, which is a sheet of paper, a plastic sheet, or the 
like, is conveyed in direction denoted by arrow B by the paper feed roller 
207 and the pinch roller 209. After the record head 202 has recorded an 
image on the record material 208, the record material 208 is discharged in 
direction denoted by arrow C by a paper discharge roller or the like. The 
paper feed roller 207 is oscillationally supported about a shaft 235 that 
works as a supporting point through arm portions 233 and 234. The arm 
portions pivot both edge portions of the paper feed roller 207. 
A cap member 261 is disposed at a home position of the record head 202. The 
cap member 261 is opposed to an ink discharge opening 81 of the record 
head 202. The cap member 261 is made of an air-tight elastic member such 
as rubber. The cap member 261 is moved by a drive means (not shown) so as 
to close or open the ink discharge opening 81. When an image is not 
recorded, the head cartridge 201 is moved to the home position. At this 
point, the cap member 261 is moved forward so as to air-tightly close the 
ink spray orifice 82 of the record head 202. A wiping blade 263 is 
disposed adjacent to the cap member 261. The wiping blade 263 is disposed 
on the holder 262. The wiping blade 263 is made of an elastic member such 
as silicon rubber or urethane rubber. In synchronization with the motion 
of the carriage 204, the wiping blade 263 removes adhered substances (such 
as ink, paper fibers, and dust) from the ink discharge opening 81 of the 
record head 202. 
FIG. 22 is a vertical sectional view in a paper feed direction of the 
recording apparatus of FIG. 21. In FIGS. 21 and 22, arm portions 233 and 
234 that pivot the paper feed roller 207 are oscillationally disposed 
about a shaft 235. The arm portions 233 and 234 are biased to the pinch 
roller 209 by a tension spring 236 (see FIG. 22). Thus, the paper feed 
roller 207 is biased to the pinch roller 209 on the fixed shaft. 
In FIG. 21, forward edge portions of the arm portions 233 and 234 are 
brought into contact with release cams 238 and 238 that are rotated by a 
release lever 237, respectively. Thus, when the release lever 237 is 
rotated in direction denoted by arrow D, the release cams 238 and 238 are 
rotated, thereby separating the paper feed roller 207 from the pinch 
rollers 209. A gear 239 is secured to one edge of the shaft portion of the 
paper feed roller 207. The paper feed roller 207 is rotated by a motor 
(not shown) through the gear 239. The carriage 204 is reciprocated by a 
carriage motor (not shown). 
In FIG. 22, a paper discharge system is disposed downstream (in a record 
material conveying direction) of the record head 202. The paper discharge 
system is constructed of the paper discharge roller 244 and the pinch 
roller 245. Alternatively, the paper discharge system is constructed of 
the paper discharge roller 244 and the spur 246. In addition, an ink spray 
portion (having a plurality of ink discharge openings) is disposed on an 
ink discharge surface 81 of the record head 202. The width (namely, the 
length in the paper feed direction) of the ink discharge portion is w. 
In FIGS. 21 and 22, a record material guide means 265 is disposed adjacent 
to and upstream (in the conveying direction of the record material 208) of 
the record head (record means) 202. The record material guide member 240 
guides the record material 208 that is tensioned and pinched by the paper 
feed roller 207 and the pinch roller 209. When the forward edge portion 
(paper contact portion 266) of the record material guide member 265 is 
brought into contact with the record material 208, the record material 208 
is guided along a predetermined conveying path. In this embodiment, the 
record material guide means 265 is constructed of a plate-shaped member 
that covers the paper width. 
The record material guide means 265 has a support member 267 that rotatably 
supports the pinch roller 209. An opening 268 is formed corresponding to 
the pinch roller 209 of the record material guide means 265. The pinch 
roller 209 is in contact with the paper feed roller 207 through the 
opening portion 268. 
In FIG. 22, the diameter of the pinch roller 209 is small. The pinch roller 
209 is disposed at a position very close to the ink spray portion w of the 
record head 202. In addition, as shown in FIG. 22, the paper feed roller 
207 and the pinch roller 209 are non-coaxially abutted. In other words, 
the paper feed roller 207 is disposed downstream (in the paper feed 
direction) of a pressure point (pinch portion) of the pinch roller 209 
(namely, the paper feed roller 207 and the pinch roller are non-coaxially 
disposed) so that the record material 208 is conveyed along a sheet 
contact portion 266 of the record material guide means 265. The record 
material guide means 265 is disposed on the record means 201. The record 
material guide means 265 extends along the main scanning direction of the 
record means 201. 
Thus, a paper feed roller 207 and a pinch roller 209 are disposed so that a 
record material 208 is conveyed along a record means 202. An abut portion 
of a pinch roller 209 to the paper feed roller 207 and an abut portion of 
a pinch roller 245 (including a spur 246) to a paper discharge roller 244 
are disposed adjacent to the record means 202. A record material guide 
means 265 is disposed adjacent to the record means 202. The record 
material guide means 265 extends along main scanning direction of the 
record means 202. The record material guide means 265 is opposed to the 
record means 202. The record material guide means 265 also works as a hold 
member of the pinch roller 209. 
According to the recording apparatus shown in FIGS. 21 and 22, the 
following effects can be obtained. As a first effect, since the trailing 
edge of the record material 208 is pinched by the pinch roller 245 or the 
spur 246 and the paper discharge roller 24, an image can be recorded on 
the record material 208 until the trailing edge of the record material 208 
is just separated from the record material guide means 265. As a second 
effect, since the record material guide means 265 works for the entire 
width of the record material 208, the record material 208 can be 
accurately fed (conveyed) without being swelled and waved. As a third 
effect, since the record material guide means 265 is fixed, the record 
material 208 can be precisely fed. 
As a fourth effect, since the record material guide means 265 is 
constructed with high rigidity, when the support mechanism of the pinch 
roller 209 or the like is disposed on the guide means 265, the rigidity of 
the apparatus can be enhanced, thereby improving the recording accuracy. 
As a fifth effect, since the record material 208 is guided by the guide 
means 265 in the vicinity of the record portion, the record material can 
be much prevented from being in contact with the ink discharge portion of 
the record head 202. As a sixth effect, since almost the limit of the 
trailing edge of the record material 208 is pinched, an image can be 
recorded almost at the trailing edge. In addition, since the leading edge 
is guided, the accuracy of the leading edge position is improved. Thus, 
the record accuracy can be improved. 
When the record material guide means 265 is fixed, the distance between the 
ink discharge surface 81 of the record head 2 and the record material 208 
is always kept constant regardless of the thickness of the paper to be 
used. When the distance should be changed corresponding to the record 
head, with a height adjustment mechanism of the record material guide 
means 65, the distance can be adjusted. Since the record material guide 
means 265 is disposed adjacent to the ink discharge portion w of the 
record head, the record material guide means 265 works as a protector 
against the ink discharge portion or the record material 208. In this 
embodiment, the paper feed roller 207 is tensioned to the pinch roller 209 
on the fixed axis. However, it should be noted that the record material 
guide means 265 and the pinch roller 209 may be tensioned to the paper 
feed roller 207 on the fixed axis. 
In the above-described embodiments, the recording apparatuses are ink jet 
recording apparatuses. However, the present invention is not limited to 
the ink jet recording apparatus. Rather, the present invention may be 
applied to a wire-dot type recording apparatus, a heat sensitive recording 
apparatus, a thermal transfer type recording apparatus, and the like. In 
these recording apparatuses, the same effects as the above-described 
embodiments can be obtained. In the above-described embodiments, the 
serial type recording apparatus, which moves the record means in main 
scanning direction, is explained. However, the present invention may be 
applied to a line type recording apparatus. The line type recording 
apparatus has a line record means that records an image in sub-scanning 
direction. In the line type recording apparatus, the same effects as the 
above-described embodiments can be obtained. 
In the above-described embodiments, a monotone recording system, which 
records an image in a single color, is described. However, the present 
invention may be applied to a color recording system and a tone recording 
system. In these systems, a plurality of record means are used. However, 
the color recording system records an image in a plurality of colors 
corresponding to the record means, whereas the tone recording system 
records an image in a plurality of tones of a single color corresponding 
to the record means. In other words, the present invention may be applied 
to a variety of systems regardless of the number of record means and the 
number of recording colors. In these cases, the same effects as 
above-described embodiments can be obtained. In the above-described 
embodiment, the head cartridge, where the record means is incorporated 
with the ink tank, is used. However, the record means may be separated 
from the ink tank and they may be connected with an ink supply tube. Thus, 
the present invention may be applied to various constructions of the 
record means and the ink tank. In these constructions, the same effects as 
the above-described embodiments can be obtained. 
The present invention may be applied to the ink jet recording apparatus 
with a record means (record head) using an electric-mechanical converting 
element such as piezo element. However, the ink jet recording apparatus 
with a record means that discharges ink using thermal energy can provide 
excellent effects where an image can be densely and precisely recorded. 
It is preferable to employ a drive signal of the pulse signal type 
disclosed in U.S. Pat. No. 4,463,359 and U.S. Pat. No. 4,345,262. 
Furthermore, in a case where conditions for determining the temperature 
rise ratio on the aforesaid heated surface disclosed in U.S. Pat. No. 
4,313,124 are adopted, a further excellent recording operation can be 
performed. 
In addition to the structure (a linear liquid passage or a perpendicular 
liquid passage) of the recording head formed by combining the discharge 
ports, the liquid passage and the electrothermal conversion member as 
disclosed in the aforesaid specifications, a structure disclosed in U.S. 
Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600 in which the heated portion 
is disposed in a bent portion is included in the scope of the present 
invention. Furthermore, the present invention can effectively be embodied 
in a structure in which a common slit is made to be the discharge portion 
of a plurality of electrothermal conversion members and which is disclosed 
in Japanese Patent Laid-Open No. 59-123670 and a structure in which an 
opening for absorbing thermal energy pressure wave is formed to align to 
the discharge port and which is disclosed in Japanese Patent Laid-Open No. 
59-138461. 
A full line type recording head having a length which corresponds to the 
width of the maximum recording medium which can be recorded on by the 
recording apparatus may be a structure capable of realizing the aforesaid 
length and formed by combining a plurality of recording heads as disclosed 
in the aforesaid specifications or a structure formed by a integrally 
formed recording head. The present invention will enable the aforesaid 
effects to be exhibited further effectively. 
In addition, the present invention can also be effectively adapted to a 
structure having an interchangeable chip type recording head which can be 
electrically connected to the body of the apparatus or to which ink can be 
supplied from the body of the apparatus when it is mounted on the body of 
the apparatus or a cartridge type recording head integrally formed to the 
recording head. 
When the record head of the recording apparatus of the present invention is 
provided with a recovery means and a preliminary means, the effects of the 
present invention can be more stably accomplished. Examples of these means 
are a capping means, a cleaning means, a pressuring/sucking means for the 
record head, an electric-thermal converting element, another heating 
element, a preliminary heating means thereof, and a preliminary 
non-recording discharge mode. 
In the above-described embodiments, one record head corresponding to for 
example black ink is used. However, the number of record heads is not 
limited to one. Instead, a plurality of record heads corresponding to 
colors or tones may be used. In other words, the present invention may be 
very effectively applied to any constructions of a single-head 
single-color (for example, block) system, a head-ink incorporated system, 
a multi-color system, and a sull-color system (mixed colors). 
In addition, according to the present invention, ink is explained as 
liquid. However, the ink for use in the present invention may be a 
temperature-softening (liquefying) ink. In an ink jet system, the 
temperature of ink is controlled so that the viscosity thereof becomes 
stable in the range of 30.degree. C. to 70.degree. C. Thus, ink that is 
liquified corresponding to a record signal may be used. The temperature 
rise due to heat energy can be prevented by using status change energy 
from solid state to liquid state of ink. In other words, the present 
invention can be applied to any construction where ink is liquified by 
heat energy. 
In this case, as disclosed in Japaense Patent Laid-Open Nos. 54-56847 and 
60-71260, ink that is held in a cavity portion or a through-hole of a 
porous sheet may be opposed to an electric-thermal converting element. In 
the present invention, the above-described membrane boiling system is 
preferably employed. In addition to the image output terminals of 
information processing units such as computers, the ink jet recording 
apparatus according to the present invention may be used as copiers with a 
reader, facsimile units with transmission and reception functions, and so 
forth. 
As described above, according to the fifth embodiment, which is a recording 
apparatus with a record means for recording an image on a record material, 
a paper feed roller support member pivots both edges of a paper feed 
roller about a roller drive shaft. A spring is disposed on the paper feed 
roller support member so as to tension the paper feed roller to the pinch 
roller. A lever portion that releases the paper feed roller from the pinch 
roller against the spring tension is disposed on one side of the roller 
support member. Thus, the support mechanism on both sides of the paper 
feed roller are incorporated. Thus, the recording apparatus with the sheet 
roller support mechanism that can securely perform the release operation 
can be constructed with fewer constructional members and in a smaller 
space. 
According to the sixth embodiment, which is a recording apparatus with a 
record means that records an image on a recording sheet, a pair of 
extension roller portions that rotate along with a paper feed roller are 
coaxially disposed outside a pair of bearings disposed both edges of the 
paper feed roller. The paper feed roller, the extension roller portions, 
and the pinch roller are tensioned so that the record material is equally 
pressed on the full width thereof. Thus, the length of the paper feed 
roller can be functionally increased without needing to increase the size 
of the apparatus. In addition, the paper feed roller can be prevented from 
getting loose. As a result, a recording apparatus that has a small 
diameter roller and high sheet feed accuracy can be accomplished. 
According to the seventh embodiment, which is a recording apparatus with a 
record means that records an image on a record material, a record material 
guide member is disposed adjacent to and upstream of a record means. At 
least a contact portion of the record material guide member to the record 
material is formed of an outer layer that has water repelling 
characteristics, low frictional coefficient to the record material, and 
high wearing resistance. Thus, the record material is smoothly fed at the 
contact portion. Consequently, the load of the paper feed motor can be 
reduced. As a result, the record material can be prevented from being 
scratched and stained. In addition, since the record material can is kept 
from being twisted and wrinkled while an image is recorded. Thus, a 
recording apparatus with a paper feed mechanism that improves recording 
accuracy and recording quality can be provided. 
According to the eighth embodiment, which is a recording apparatus with a 
record means that records an image on a record material, a groove portion 
is disposed on a paper feed roller. A sheet contact portion of a detector 
that detects the record material is disposed inside the groove portion and 
between pinch rollers so as to detect whether the record material is 
present at a position of a record material pressing drive portion in a 
paper feed direction. Thus, the size of the recording apparatus can be 
reduced. In addition, the record material can be detected at a position 
where the record material is most tensioned. As a result, the record 
material can be securely detected without being moved and a recording 
apparatus with a paper feed mechanism that reduces time lag and distance 
lag between paper detection and image recording can be provided. 
According to the ninth embodiment, which is a recording apparatus with a 
record means that records an image on a record material, axial positions 
of a paper feed roller and a pinch roller are disposed so that the record 
material is conveyed along the record means. In addition, a contact 
portion of the paper feed roller and the pinch roller and a contact 
portion of a paper discharge roller and its pinch roller are disposed 
adjacent to the record means. A record material guide means that extends 
in main scanning direction of the record means is disposed adjacent to the 
record means. The record material guide means works as a hold member of 
the pinch roller. Thus, an image can be recorded from a leading edge to a 
trailing edge of the record material. Thus, the sheet feed operation can 
be accurately performed. In addition, swelling and waving of the record 
material can be prevented.