JP2002307668A - Elevating device of recording head and recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove backlash between structural elements of an elevating mechanism, to remove the backlash by a predetermined urging force irrespective of an elevating position of a recording head and to reduce a driving motor in size. SOLUTION: Spring members 30A, 30B urge a recording head support member 10B by an urging force not less than a predetermined level to suppress the backlash.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a recording head elevating device for moving a recording head up and down, and a recording apparatus.

[0002]

2. Description of the Related Art In an ink jet recording apparatus, generally, a recording head disposed in a recording system is moved relative to a recording surface of a recording medium or a capping member of a recovery processing unit for performing a recording head recovery process. A device provided with an elevating device for raising and lowering is provided for practical use.

[0003] Such an elevating device includes, for example, a recording head support member for supporting a recording head that performs a recording operation by discharging ink onto a recording surface of a recording medium, and the supporting member is connected to a recording surface or a recording surface of the recording medium. It is configured to include a drive mechanism that moves up and down relative to a capping member or the like of the recovery processing unit, and a drive motor.

[0004] The driving mechanism changes a recording head support member to a recording surface of a recording medium or a capping member of a recovery processing unit based on a driving force transmitted from a driving motor transmitted through a speed reducer having a predetermined reduction ratio. To be moved up and down. The drive mechanism moves the recording head support member up and down by, for example, screw motion.

[0005]

For example, in the case of a so-called long recording head having a relatively large number of ink ejection ports, the total weight of the recording head support member and the recording head is as described above. When a driving motor having a relatively small output is used because it is relatively large, it is necessary to set the reduction ratio of the reduction gear to be relatively large. However, if the speed reduction ratio of the speed reducer is set to a relatively large value, the speed at which the recording head support member moves up and down is reduced, so that there is a limit in using a drive motor having a relatively small output.

[0006] Further, for example, a play between a screw shaft and a screw hole, which causes a screw motion to be performed in the above-described drive mechanism,
Since there is a so-called backlash between mechanical elements, when the capping and blades of the recovery processing unit abut against the ink ejection portion of the recording head with a predetermined pressure, the recording head support member and the recording head are pressed to cause the backlash. Since it moves by a corresponding moving distance, there is a possibility that capping and wiping may not be performed accurately.

[0007] In view of the above problems, the present invention relates to a recording head elevating device for moving a recording head up and down and a recording apparatus, wherein backlash between components of an elevating mechanism can be eliminated. Regardless of the elevation position of the recording head, the backlash between the components of the elevation mechanism can be removed with a constant urging force, and furthermore, the elevation device and the recording device for the recording head can reduce the size of the driving motor. The purpose is to provide.

[0008]

In order to achieve the above-mentioned object, an apparatus for lifting a recording head according to the present invention supports a recording head which discharges a liquid and performs a recording operation on a recording surface of a recording medium. A recording head support, a driving force transmission portion provided on the recording head support, for transmitting a driving force for reciprocating the recording head support, and a driving force transmission portion engaged with the driving force transmission portion via a tooth portion and supplied. A driving force transmission unit that transmits the driving force to the driving force transmission unit, a driving force supply unit that is connected to the driving force transmission unit, and supplies the driving force to the driving force transmission unit, and a recording head support unit. And an urging member for urging in the direction.

A recording head lifting device according to the present invention is provided on a recording head support for supporting a recording head for performing a recording operation on a recording surface of a recording medium. The screw portion includes a screw shaft member formed along the moving direction of the recording head support portion, and a second screw portion fitted to the first screw portion of the screw shaft member. A driving force transmitting member for transmitting the driving force to the member, a driving force supply unit connected to the driving force transmitting member for supplying the driving force, and a screw shaft member or the driving force transmitting member being directly or indirectly attached in a predetermined direction. And a biasing member for biasing.

Further, the recording apparatus according to the present invention includes a recording head for discharging a liquid and performing a recording operation on a recording surface of a recording medium, a recording head support for supporting the recording head, and a recording head support. A driving force transmitting portion for transmitting a driving force for reciprocating the recording head support portion, and a driving force transmitted to the driving force transmitting portion by being engaged with the driving force transmitting portion via a tooth portion and supplied to the driving force transmitting portion. A driving force transmitting unit, a driving force supplying unit connected to the driving force transmitting unit for supplying driving force to the driving force transmitting unit, and an urging member for urging the recording head support unit in a predetermined direction. Be composed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows a schematic configuration of a main part of a first embodiment of a recording head lifting / lowering apparatus according to the present invention, together with a configuration of an ink jet recording apparatus to which the apparatus is applied.

In FIG. 2, an ink-jet recording apparatus uses a recording head 6 to be described later to transfer a sheet Pa as a recording medium.
A transport unit 2 that transports the recording heads 6Y to 6T according to the Y to 6T recording operation, a recovery processing unit 8 that performs recovery processing of the recording heads 6Y to 6T, and a recording operation on the recording surface of the paper Pa Heads 6Y to 6T for performing
And a lifting device 10 for causing Y to 6T to approach the recording surface of the paper Pa to take a recording position, or to separate from the transport unit 2 to take a standby position. FIG. 2 shows a state where the recording heads 6Y to 6T are arranged at the recording positions.

The transport section 2 is disposed opposite to the upstream and downstream sides of a transport path formed along the direction indicated by the arrow C in FIG. 2 below the lifting device 10 and the recording heads 6Y to 6T. Transport rollers 2A and 2B, and a transport belt 4 wound around the transport rollers 2A and 2B, and although not shown, connected to one end of the transport roller 2B and accompanied by the transport roller 2A via the transport belt 4. And a drive motor for rotating.

As shown in FIG. 1, the lengths of the conveying rollers 2A and 2B in the axial direction and the width of the conveying belt 4 are set to be longer than the width of a predetermined sheet Pa, respectively, as shown in FIG. The lengths along are the recording heads 6Y to 6T
Is set longer than the length in the arrangement direction.

Although not shown, a predetermined charge is generated on the surface of the transport belt 4 by an electrostatic induction action of a charger disposed on the upstream side of the transport path, and the paper Pa is held by its suction force. It is to be transported.

The drive motor is controlled based on a drive control signal from a control unit (not shown). Accordingly, the transport belt 4 intermittently transports the paper Pa placed according to the recording operation of the recording heads 6Y to 6T.

As shown in FIGS. 1 and 2, the recovery processing unit 8 includes recording heads 6Y, 6M, 6
Capping members 8Y, 8M, 8C, 8B, and 8T provided corresponding to C, 6B, and 6T, respectively.
And a plurality of blade members 9 provided adjacent to the capping members 8Y to 8T, respectively.

The capping members 8Y, 8M, 8C, 8B
Since the capping member 8T has the same structure as the capping member 8T, the capping member 8T will be described.
Description of Y to 8B is omitted.

The capping member 8T has an open end at the top, and is moved in the direction indicated by the arrow K in FIG. 1 when the recording head 6T takes a predetermined standby position separated from the transport path. The leading end surface is brought into close contact with the entire surface of the ink ejection port forming surface that has been lowered. Further, inside the capping member 8T, there is provided a liquid absorber for temporarily absorbing and holding the processing liquid discharged from the recording head 6T. The liquid absorbed by the liquid absorber is collected in a waste tank (not shown) via a waste tube connected thereto.

A thin blade member 9 is provided on the capping member 8T so as to be substantially parallel to and adjacent to the capping member 8T. When the recording head 6T takes a predetermined standby position, the blade member 9 is moved in a direction opposite to the direction indicated by the arrow K in FIG.
The ink or the like attached to the ink ejection port forming surface of T is wiped off.

As shown in FIG. 1, the capping members 8Y to 8B are fixed in the unit base 16 at predetermined intervals in parallel with each other and in a direction substantially perpendicular to the direction in which the paper Pa is transported. By being connected. The unit base 16 is supported by a guide member (not shown) so as to be able to reciprocate a predetermined distance along the transport direction of the paper Pa. Unit base 16
Has a space between the capping members 8Y to 8B so that the ink ejection portions of the recording heads 6Y to 6T can enter. A rack member 18 is provided at one end of the unit base 16, as shown in FIG. The rack member 18 is engaged with a pinion gear fixed to an output shaft of a drive motor 20 provided at a portion of the housing facing one end of the capping member 8T.

The drive motor 20 is controlled based on a drive control pulse signal from a control unit (not shown).

Therefore, when the recording heads 6Y to 6T take a predetermined standby position, when the driving motor 20 is activated and is rotated by a predetermined rotation angle in one direction, as shown in FIG. The unit base 16 is moved in the direction indicated by the arrow K, and the capping members 8Y to 8T are moved to positions just below the recording heads 6Y to 6T. Then, each of the recording heads 6Y to 6T is lowered, and a predetermined recovery process for each of the recording heads 6Y to 6T, for example, suction or preliminary ejection operation of each of the recording heads 6Y to 6T is performed. The clogging of the discharge port and the like are eliminated.

On the other hand, when the recording heads 6Y to 6T take a predetermined standby position, the driving motor 20 is set in an operating state, and when the driving motor 20 is rotated by a predetermined rotation angle in the other direction, as shown in FIG. The unit base 16 is moved in a direction opposite to the direction indicated by the arrow K. As a result, as shown in FIG. 2, the capping members 8 </ b> Y to 8 </ b> T are moved to the most downstream end between the recording heads 6 </ b> Y to 6 </ b> T, and the blade member 9 wipes the ink discharge port forming surface. Will be performed.

The recording heads 6Y to 6B are sequentially arranged from the upstream side to the downstream side of the transport path, and eject yellow, magenta, cyan, and black inks, respectively. The recording head 6T uses the paper Pa
The processing liquid for insolubilizing each ink adhered to the recording surface is ejected. The ink and the processing liquid are sequentially supplied from an ink tank and a processing liquid tank (not shown).

Each of the recording heads 6Y to 6T is, for example, a bubble jet (registered trademark) type, and has a plurality of ink ejection ports 96 at a portion facing the recording surface of the paper Pa to be transported, as described later. A recording element substrate 92 having an ink discharge port forming surface 91 to be formed is provided. The plurality of ink ejection ports 96 of the ink ejection port forming surface 91 are arranged and formed over the width of the recording area of the paper Pa, that is, the length of the short side of the paper Pa in a direction substantially orthogonal to the transport direction of the paper Pa. ing.

An electrothermal conversion element 94 is provided in each of the ink flow paths communicating with the plurality of ink discharge ports 96. The electrothermal transducer 94 is controlled based on a drive control pulse signal from a control unit (not shown).

Thus, the ink is heated by controlling the electrothermal conversion element 94 based on the drive control pulse signal formed based on the data representing the image formed on the recording surface of the paper Pa. Ink ejection port 96
Is ejected toward the recording surface of the paper Pa via.

The recording element substrate 92 has, for example, a thickness of 0.5.
It is manufactured using a silicon wafer of １1 mm. As shown in FIG. 12A, the recording element substrate 92
Five elongated ink supply ports 95 arranged in parallel with each other
Are formed corresponding to the ink and the processing liquid to be used.

On both sides of each ink supply port 95, ink chambers 93 are formed in two rows so as to sandwich the ink supply port 95. The ink chambers 93 are arranged at predetermined intervals along the longitudinal direction of the ink supply port 95. Each of the ink chambers 93 is provided with an electrothermal conversion element 94 as a recording element and a discharge port 96 formed to face the electrothermal conversion element 94 for discharging ink droplets and the like.

In FIG. 12A, the ink supply port 95
Are arranged in a so-called zigzag pattern even at half a pitch from each other. The intervals between the ejection ports 96 arranged along the longitudinal direction of the ink supply ports 95 corresponding to the inks of the respective colors are such that the intervals between the ink chambers 93 corresponding to the ejection ports 96 in each row are arranged at a pitch of 600 dpi. It looks like 1200dpi
It is set in a high-density arrangement state.

The electrothermal transducer 94 and the electrode wiring formed of aluminum or the like and supplying power to the electrothermal transducer 94 are formed on the surface of the silicon wafer by a film forming technique. The other terminal of the electrode wiring is a bump 9 made of gold or the like and protruding from the surface of the recording element substrate 92.
8 are formed.

The electrothermal conversion element 94 is, for example, a part of a heating resistor layer that is not covered with an electrode wiring formed of aluminum or the like. The heating resistor layer is formed of, for example, TaN, TaSiN, Ta-Al, or the like.
It has a sheet resistance of 53Ω. Further, these electrothermal conversion elements 94 and electrode wirings are 4000 × 10
It is covered with a protective layer 20 made of silicon nitride (SiN) having a thickness of ^-10 (m) (4000 angstroms). Further, a cavitation-resistant layer made of tantalum (Ta) having a thickness of 2300 × 10 ⁻¹⁰ (m) (2300 Å) is formed on the surface of the protective layer 20 on the electrothermal transducer 94.

The above-described ink supply port 95 is formed by anisotropic etching using the crystal orientation of a silicon wafer used as the recording element substrate 92. That is,
When the surface of the silicon wafer is <100> and has a crystal orientation of <111> in its thickness direction, for example, an alkaline anisotropic material such as potassium hydroxide (KOH), tetramethylammonium hydroxide (TMAH), or hydrazine is used. Etching is performed to a desired depth with a selectivity in an etching direction by using a neutral etching solution. Also,
The ink chamber 93 and the ejection port 96 are formed by a photolithography technique. When drive power is supplied to the electrothermal conversion element 94, for example, 4 picoliter ink droplets are ejected from the ejection port 96.

In the example shown in FIG.
The shape of the ejection port 96 is circular, but is not limited to this example. For example, as shown in FIG. 12B, the shape of the ejection port 96a of the ink ejection port formation surface 91 ′ is rectangular or polygonal. May be a star shape.

At this time, an image is formed on the recording surface of the paper Pa by sequentially performing the recording operations of the recording heads 6M to 6B from the recording head 6Y and superimposing the respective inks. By discharging the processing liquid by 6T, an insolubilization process is performed on the image. The upper portions of the recording heads 6Y to 6T are supported by a recording head support member 10B described later.

The lifting device 10 is, as shown in FIG.
At each corner of the recording head support member 10B, the recording heads 6Y to 6Y
Four screw shafts 22 provided along the direction of 6T elevating movement, and four screw shafts each having a female screw hole rotatably supported by each bracket member 26 of the base plate 14 and fitted to the screw shaft 22. And one end of each of the screw shafts 22 connected to the recording head support member 10B,
It includes spring members 30A and 30B as urging members for urging the recording head supporting member 10B upward, and a stepping motor 36 for rotating each pulley 24 via a timing belt 28.

One end of each screw shaft 22 is fixed to the upper end surface of the four corners of the recording head support member 10B.
They are provided in parallel with each other. Each screw shaft 2
The other end of 2 extends upward through a through hole provided in base plate 14.

One end of the base plate 14 is bent and fixed to the housing 12 in the apparatus. Base plate 1
4, a bracket member 26 supporting each pulley 24 is provided corresponding to each pulley 24. A stepping motor 36 is provided between the screw shafts 22 on one side of the pair of screw shafts 22 with the lower conveying path supported by a bracket member. A pulley is fixed to the output shaft of the stepping motor 36. A timing belt 28 is wound around a pulley provided on each pulley 24 and an output shaft of the stepping motor 36. Stepping motor 3
The idle rollers 38A and 38B are provided between the pulley 24 provided on the output shaft 6 and the pulley 24, respectively.

The stepping motor 36 is controlled based on a drive control pulse signal from a control unit (not shown). Therefore, when the stepping motor 36 is activated and rotated in the direction indicated by the arrow in FIG.
4 is rotated in the same direction, so that each screw shaft 22 is raised by a predetermined amount together with the recording head support member 10B and the recording heads 6Y to 6B.

On the other hand, when the stepping motor 36 is activated and is rotated in the direction opposite to the direction shown by the arrow in FIG. 1, each pulley 24 is rotated in the same direction, so that each screw shaft 22 is Recording head support member 10B
And the recording heads 6Y to 6B are lowered by a predetermined amount.

Further, the sides of the base plate 14 perpendicular to the direction in which the paper Pa is transported are
Spring member 30A wound around each of 2A and 32B
And 30B are provided. Support shafts 32A and 3
Both ends of 2B are respectively supported by a pair of stays 34A and 34B formed integrally with the base plate 14. An opening 14a is formed between each of the stays 34A and 34B. One ends of the spring members 30A and 30B are connected to the recording head support member 1 respectively.
0B is connected to the connecting portion 10A.

As shown in FIG. 3, the spring members 30A and 30B are wound around the support shafts 32A and 32B, respectively, in the form of a tightly wound spring.

When the recording head supporting member 10B to which one ends of the spring members 30A and 30B are connected is lowered, one ends of the spring members 30A and 30B are pulled out as shown by a two-dot chain line in FIG.

At this time, the tension P applied to the recording head supporting member 10B by the spring members 30A and 30B is
As shown in FIG. 4, a predetermined value Po is obtained without being influenced by the increase or decrease in the amount of pulling out λ of the spring members 30A and 30B.
It is said.

FIG. 4 shows the relationship between the tension P of the spring members 30A and 30B and the amount of pullout λ, with the vertical axis representing the tension P and the horizontal axis representing the amount of pullout λ. Generally, the tension P in the coil spring increases in proportion to the amount of elongation from the initial value, that is, the amount of pullout λ, as shown by a straight line Ls in FIG. 4, for example, whereas the tension P of the spring members 30A and 30B increases. The tension P is, as indicated by the straight line Lt, the drawing amount λ.
Is maintained at the predetermined value Po irrespective of.

Therefore, the spring members 30A and 30B are
The tension of the predetermined value Po is always exerted in the direction of raising the recording head support member 10B without depending on the amount of elevation of the recording head support member 10B. Thereby, the play of the screw thread of the screw shaft 22 provided on the recording head support member 10B and the valley of the female screw hole of the pulley 24, that is, the screw thread of the screw shaft 22 is adjusted so that the backlash is reduced. It will be in contact with the valley of the hole. The spring member 30A
The tension of the predetermined value Po of each of the recording head support member 10B and the recording heads 6Y to
It is set to a value equal to about half of the total weight of 6T. As a result, even in the recovery processing, the backlash is reduced even when the recording heads 6Y to 6T are pressed upward by the recovery processing units 8Y to 8T in the direction opposite to the direction of gravity. There is no risk that the heads 6Y to 6T will rise above the predetermined position, and good recovery processing and wiping will be performed.

The spring members 30A and 30B are
Although it is provided at a location, it is not limited to such an example, and three or more may be provided.

As described above, the recording head supporting member 10B is urged by the spring members 30A and 30B, so that the recording head supporting member 10B and the recording heads 6Y to 6Y are formed.
The driving force required for the stepping motor 36 to rotate each pulley 24 to raise and lower the 6T is reduced. Therefore, it is possible to use the stepping motor 36 having a relatively small output.

FIG. 5 shows a schematic configuration of a main part of a second embodiment of a recording head lifting / lowering apparatus according to the present invention, together with a configuration of an ink jet recording apparatus to which the apparatus is applied.

In the example shown in FIG. 1, the elevating device includes a screw shaft 22 and a pulley 24. Instead, the elevating device is provided with a rack 50RA and a rack 50RA provided on the recording head support member 50. 5
0RB and the pinion gears 60a and 56a meshed with the rack portions 50RA and 50RB. In the example shown in FIG. 5, FIG.
In the example shown in FIG. 1, the same components are denoted by the same reference numerals, and the description thereof will not be repeated.

The recording head support member 50 disposed above the paper Pa conveyance path has the above-described recording head 6 inside.
Y, 6M, 6C, and 6B are sequentially held from the upstream side to the downstream side of the transport path. The recording head supporting member 50 is supported so as to be able to move up and down between housings 70 arranged opposite to each other at a predetermined interval.

The lifting device 46 includes a recording head support member 50.
Racks 50RA and 50RB provided at respective corners of the ends corresponding to the downstream side and the upstream side of the transport path along the direction in which the recording heads 6Y to 6B move up and down.
A rotating shaft 60 having a pinion gear 60a meshing with each rack portion 50RA, a driving motor 64 connected to one end of the rotating shaft 60, and a rotating shaft 56 having a pinion gear 56a meshing with each rack portion 50RB. , One end of which is connected to the recording head support member 50 and the recording head support member 50 and the rack portions 50RA and 50RA.
Spring member 30 as a biasing member for biasing 0RB upward
A and 30B.

Each of the racks 50RA and 50RB is guided by the inner surface of the housing 70 when ascending and descending.

One end of the rotating shaft 60 is rotatably supported by the housing 70, and the other end of the rotating shaft 60 is connected to the output shaft of the driving motor 64. The drive motor 64 is fixed to the housing 70 via a bracket member. The drive motor 64 is controlled based on a drive control signal from a control unit (not shown). A pulley 72 is further fixed to the other end of the rotating shaft 60.

The rack 50R of the recording head support member 50
A pulley 58 is provided corresponding to the pulley 72 on a wall portion connecting the A and the rack portion 50RB. Pulley 5
Numeral 8 is rotatably supported by a support shaft 58a provided on its wall surface. A timing belt 62 is wound between the pulley 72 and the pulley 58.

A gear 74 is fixed to the support shaft 58a. The gear 74 is engaged with the gear 54 fixed to one end of the rotating shaft 56. Both ends of the rotating shaft 56 are rotatably supported by the housing 70, respectively.

Accordingly, when the drive motor 64 is activated and the rotary shaft 60 and the pulley 72 are rotated in the direction indicated by the arrow in FIG. 5, the pulley 58 and the gear 74 are rotated.
Are rotated in the same direction, the gear 54 and the rotating shaft 56 are rotated in the direction indicated by the arrow in FIG. 5, and the recording head supporting member 50 is lowered by a predetermined amount.

On the other hand, when the driving motor 64 is activated and the rotating shaft 60 and the pulley 72 are rotated in the direction opposite to the direction indicated by the arrow in FIG. 5, the pulley 58 and the gear 74 are rotated in the same direction. As a result, the gear 54 and the rotating shaft 56 are rotated in the direction opposite to the direction indicated by the arrow in FIG. 5, and the recording head supporting member 50 is raised by a predetermined amount.

Further, a connecting portion 5 provided on a side of the recording head supporting member 50 which is orthogonal to the sheet Pa conveying direction.
One ends of spring members 30A and 30B wound around support shafts 62A and 62B, respectively, are connected to 0A. Both ends of the support shafts 62A and 62B are supported by the housing 70, respectively.

Therefore, even in such a configuration, even in the case where the recording heads 6Y to 6T are pressed upward by the recovery processing units 8Y to 8T in the direction opposite to the direction of gravity in the recovery processing or the like. Rack 50RA
And 50RB and the pinion gears 60a meshing with the respective rack portions 50RA are reduced in backlash, so that the recording heads 6Y to 6T do not have a risk of rising above a predetermined position, so that good recovery processing and wiping are performed. Become.

FIGS. 8 and 9 show a schematic configuration of a main part of a third embodiment of a recording head lifting / lowering apparatus according to the present invention, together with a configuration of an ink jet recording apparatus to which the apparatus is applied. In the examples shown in FIGS. 8 and 9, the same components as those in the example shown in FIG. 1 are denoted by the same reference numerals.

In FIG. 8, the ink-jet recording apparatus prints a sheet Pa as a recording medium on a recording head 6 described later.
A transport unit 2 that transports the recording heads 6Y to 6T according to the Y to 6T recording operation, a recovery processing unit 8 that performs recovery processing of the recording heads 6Y to 6T, and a recording operation on the recording surface of the paper Pa Heads 6Y to 6T for performing
And a lifting device 80 for bringing Y to 6T close to the recording surface of the paper Pa to take a recording position, or separating from the conveyance unit 2 to take a standby position. In FIG. 8, the recording heads 6Y to 6T are at recording positions,
This shows a state where the recovery processing unit 8 is arranged at the standby position.

The transport section 2 is arranged opposite to the upstream and downstream sides of a transport path formed along the direction indicated by the arrow C in FIG. 8 below the elevating device 80 and the recording heads 6Y to 6T. Transport rollers 2A and 2B, and a transport belt 4 wound around the transport rollers 2A and 2B, and although not shown, connected to one end of the transport roller 2B and accompanied by the transport roller 2A via the transport belt 4. Transport roller 2B
And a driving motor for rotating the motor.

As shown in FIG. 8, the lengths of the transport rollers 2A and 2B in the axial direction and the width of the transport belt 4 are set to be longer than the width of the predetermined paper Pa, respectively, as shown in FIG. The lengths along are the recording heads 6Y to 6T
Is set longer than the length in the arrangement direction.

Although not shown, a predetermined charge is generated on the surface of the transport belt 4 by an electrostatic induction action of a charger arranged on the upstream side of the transport path, and the paper Pa is held by the suction force. It is to be transported.

The drive motor is controlled based on a drive control signal from a control unit (not shown). Accordingly, the transport belt 4 intermittently transports the paper Pa placed according to the recording operation of the recording heads 6Y to 6T.

As shown in FIGS. 8 and 9, the recovery processing unit 8 includes recording heads 6Y, 6M, 6
Capping members 8Y, 8M, 8C, 8B, and 8T provided corresponding to C, 6B, and 6T, respectively.
And a plurality of blade members 9 provided adjacent to the capping members 8Y to 8T, respectively.

The capping members 8Y, 8M, 8C, 8B
And 8T have the same structure as each other, so that the capping member 8T will be described, and the other capping members 8T will be described.
Description of Y to 8B is omitted.

The capping member 8T having an open end at the top is moved in the direction indicated by the arrow K in FIG. 8 when the recording head 6T takes a predetermined standby position separated from the transport path. At this time, the leading end surface forming the peripheral edge of the opening end is brought into close contact with the entire ink discharge port forming surface of the recording head 6T which has been lowered by a predetermined amount and stopped. Further, inside the capping member 8T, a liquid absorber that temporarily absorbs and holds the processing liquid discharged from the recording head 6T is provided. The liquid absorbed by the liquid absorber is collected in a waste tank (not shown) through a waste tube connected to the capping member 8T.

A thin blade member 9 is provided on the capping member 8T so as to be substantially parallel to and adjacent to the capping member 8T. When the recording head 6T takes a predetermined standby position, the blade member 9 is moved in the direction opposite to the direction indicated by the arrow K in FIG.
The ink or the like attached to the ink ejection port forming surface of T is wiped off.

As shown in FIG. 8, the capping members 8Y to 8B extend in the unit base 16 at predetermined intervals in parallel with each other and in a direction substantially perpendicular to the direction in which the paper Pa is transported. It is connected by being fixed so that it does. The unit base 16 is supported by a guide member (not shown) so as to be able to reciprocate a predetermined distance along the transport direction of the paper Pa. The unit base 16 has a space between the capping members 8Y to 8B so that the ink ejection portions of the recording heads 6Y to 6T can enter. Unit base 1
As shown in FIG. 8, one end of
Is provided. The rack member 18 is connected to the drive motor 2.
0 is meshed with a pinion gear fixed to the output shaft. The drive motor 20 is provided in a portion of the housing of the present device facing one end of the capping member 8T. The drive motor 20 is controlled based on a drive control pulse signal from a control unit (not shown).

Therefore, when the recording heads 6Y to 6T take a predetermined standby position, the driving motor 20 is set in an operating state and is rotated by a predetermined rotation angle in one direction, as shown in FIG. With the movement of the rack member 18, the unit base 16 is moved in the direction indicated by the arrow K, and the capping members 8Y to 8T are moved to positions just below the recording heads 6Y to 6T. Then, each recording head 6
After Y to 6T are lowered and stopped, each recording head 6Y
A predetermined recovery process is performed for the recording heads 6Y to 6T, for example, and a preliminary ejection operation of each of the recording heads 6Y to 6T is performed.
As a result, clogging of the ink ejection ports and the like are eliminated.

On the other hand, when the recording heads 6Y to 6T take a predetermined standby position, the drive motor 20 is set in the operating state and the unit base 16 is indicated by an arrow K when it is rotated by a predetermined rotation angle in the other direction. Moved in the opposite direction. As a result, the capping members 8Y to 8T are moved to the most downstream end between the recording heads 6Y to 6T, and the blade member 9 performs the wiping operation on the ink discharge port forming surface.

The recording heads 6Y to 6B are sequentially arranged from the upstream side to the downstream side of the transport path, and eject yellow, magenta, cyan, and black inks, respectively. The recording head 6T uses the paper Pa
The processing liquid for insolubilizing each ink adhered to the recording surface is ejected. The respective inks and the processing liquid are sequentially supplied to the recording heads 6Y to 6B from an ink tank and a processing liquid tank (not shown).

As described above, each of the recording heads 6Y to 6T is, for example, of a bubble jet type, and has a plurality of ink ejection ports formed at a portion facing the recording surface of the paper Pa to be conveyed. A recording element substrate 92 having a formation surface 91 is provided.

Therefore, as described above, the recording heads 6M to 6M to 6M to 6M
An image is formed by performing the printing operation of B and overlapping the respective inks, and finally, the processing liquid is ejected by the printing head 6T, so that the image is insolubilized. The upper portions of the recording heads 6Y to 6T are supported by a recording head support member 80B described later.

As shown in FIGS. 8 and 9, four lifting devices 80 are provided at each corner of the recording head support member 80B along the direction in which the recording heads 6Y to 6T move up and down. The shaft 122, three pulleys 150 having female screw holes respectively fitted to three of the four screw shafts 122, and the other of the four screw shafts 122 are fitted to the remaining screw shafts 122. A compound turning member 130 having a female screw hole (see FIG. 6), and an urging mechanism 121 for urging the screw shaft 122 in one direction along the axial direction with respect to each pulley 150 and the compound turning member 130 (FIG. 7) Step) for rotating the composite rotating member 130 and rotating each pulley 150 via the timing belt 128. It is configured to include a Gumota 136.

The four screw shafts 122 are arranged as shown in FIG.
As shown in FIG.
B are fixed to the upper end surfaces of the four corners and are provided in parallel with each other. As shown in FIG. 6, the other end of one screw shaft 122 of the four screw shafts 22 is fitted into a female screw hole 130a of a composite rotating member 130 rotatably provided on the base plate 14. I have.

One end of the base plate 14 is bent and fixed to the housing 12 in the apparatus. Base plate 1
On the flat surface of No. 4, bracket members 126 for guiding the upper portions of the respective screw shafts 122 are provided corresponding to the respective screw shafts 122.

As shown in FIGS. 6 and 7, the composite rotating member 130 is formed integrally with a belt pulley portion 130C on which the timing belt 128 is hung and a pinion gear 138 which will be described later. , And an engaging portion 130A provided at the center of the tooth portion 130B and engaged with a spring holding member 124 described later. The composite rotating member 130 includes a belt pulley 130C, a tooth 130B,
It has two female screw holes 130a in which the screw shaft 122 penetrating through the engagement portion 130A and the inside of the spring holding member 124 is fitted.

On the outer peripheral portion of the belt pulley portion 130C, irregularities meshing with the inner surface of the timing belt 128 are formed. The timing belt 128 includes three pulleys 150 and a belt pulley 130 of the composite rotating member 130.
It is wrapped around C.

The tooth 130B is provided with the stepping motor 13
6 is engaged with a pinion gear 138 fixed to the output shaft. The stepping motor 136 is fixed to the base plate 14 by a support member (not shown) so that the axis of the output shaft is substantially parallel to the center axis of the screw shaft 122. The pinion gear 138 is
It is engaged with the tooth portion 130B via a through hole 14b formed on the base plate 14.

The cylindrical engaging portion 130 A of the composite rotating member 130 extends upward through the through hole 14 a on the base plate 14. As shown in FIG. 7, the engaging portion 130 </ b> A has a notch 130 n and a claw portion 13 opposed to each other.
0k. Further, a groove is formed in a boundary portion between the base end portion of the engagement portion 130A and the tooth portion 130B for locking the retaining ring RL. Thereby, the composite rotating member 130
Is held by the retaining ring RL and is rotatably supported by the base plate 14. Further, when the stepping motor 136 is in the operating state, the timing belt 128 is transmitted via the pinion gear 138 and the composite rotating member 130.
Is rotated, the pulley 150 is rotated. Accordingly, the four screw shafts 122 are moved up and down together with the recording head support member 80B in accordance with the rotation direction of the pinion gear 138.

A spring holding member 124 fitted to the screw shaft 122 is provided above the engaging portion 130A. The spring holding member 124 includes, for example, a flange portion with which one end of the metal compression coil spring 32 engages,
Notch 1 of engaging portion 130A in composite rotating member 130
30n and a pair of claw portions 124k respectively engaged with each other. In addition, the spring holding member 124 has a female screw hole 1 fitted in the screw shaft 122 at the center thereof.
24a. Thereby, the spring holding member 124
Rotates in conjunction with the composite rotating member 130.

The spring holding member 124 and the composite turning member 130
A compression coil spring 132 and a spring receiver 13 for urging the spring holding member 124 in a direction away from the engagement portion 130A are provided between the engagement portion 130A and the base end of the engagement portion 130A.
4 is wound around the outer periphery of the engagement portion 130A and the claw portion 124k.

Therefore, the urging force of the compression coil spring 132 acts between the spring holding member 124 and the base end of the engaging portion 130A of the composite rotating member 130 in the direction indicated by the arrow shown in FIG. . That is, the urging mechanism 121
It is formed to include the spring holding member 124 and the composite turning member 130. In addition, such an urging mechanism 12
No. 1 is similarly provided for the remaining three screw shafts 122 and the three pulleys 150, respectively.

As a result, the flank of the screw of the screw shaft 122 and the flank of the screw of the spring holding member 124 and the composite rotating member 130 contact with a constant urging force without backlash regardless of the position of the recording head. Becomes

The stepping motor 136 is controlled based on a drive control pulse signal from a control unit (not shown). Accordingly, when the stepping motor 136 is activated and is turned in the direction indicated by the arrow in FIG. 6, the composite turning member 130 and each pulley 150 are turned in the same direction, so that each screw shaft 122 is The print head supporting member 80B and the print heads 6Y to 6B are raised by a predetermined amount.

On the other hand, when the stepping motor 136 is activated and is rotated in the direction opposite to the direction shown by the arrow in FIG. 6, the composite rotating member 130 and each pulley 150
Each screw shaft 12 is rotated in the same direction.
2 is a recording head support member 80B and a recording head 6Y
It is lowered by a predetermined amount with .about.6B.

Therefore, the flank of the screw of the screw shaft 122 provided on the recording head supporting member 80B is:
The flank of the screw of the screw shaft 122 is designed to reduce the play between the mating composite rotating member 130 and the flank of the internal thread of the pulley 150, that is, the backlash is reduced. Will be contacted. As a result, even in the recovery processing, the backlash is reduced even when the recording heads 6Y to 6T are pressed upward by the recovery processing units 8Y to 8T in the direction opposite to the direction of gravity. There is no risk that the heads 6Y to 6T will rise above the predetermined position, and good recovery processing and wiping will be performed.

FIG. 10 shows a main part of a drive unit provided with another example of the urging mechanism used in the third embodiment of the recording head lifting / lowering apparatus according to the present invention. In FIG. 10, the same reference numerals are given to the same components in the example shown in FIG. 6, and the description thereof will not be repeated.

In the example shown in FIG. 10, the urging mechanism described above is provided coaxially with the screw shaft 122 in FIG. 6, but instead, the screw shaft 122 is combined with the screw shaft 122 in order to reduce backlash. Moving member 14
An urging mechanism for urging with an urging force indirectly acting on 0 is provided.

In FIG. 10, one of the four screw shafts 122 is supported on the base plate 14 via a composite rotating member 140 so as to be able to move up and down. The compound rotating member 140 includes a gear portion 140G that meshes with the pinion gear 138, and a pulley portion 1 around which the timing belt 128 is wound.
40P. Also, the composite rotating member 14
0 indicates that the boss of the gear portion 140G is the base plate 14
Is provided on the base plate 14 so as to be rotatable in a state of being inserted into and protruding from the through hole 14a. The boss is held on the base plate 14 by a retaining ring RL provided in the groove. Further, the composite rotating member 140 has a female screw portion that fits inside the screw shaft 122.

On the other hand, the remaining three screw shafts 122 are supported by the base plate 14 so as to be able to move up and down via pulleys (not shown). The pulley has a female thread on the inside that fits into the thread of the screw shaft 122. The female screw portion is formed so as to be in the same direction as the axial traveling direction of the female screw portion of the composite rotating member 140. The so-called thread cutting directions are the same.

Further, on the outer periphery of the pulley, irregularities are formed which mesh with the teeth formed inside the timing belt 128. Thereby, the timing belt 12
Numeral 8 is wound around the pulley portion 140P of the composite rotating member 140 and three pulleys.

A gear 142 is meshed with the pinion gear 138. The gear 142 is rotatably provided on the base plate 14 with its boss being inserted into a through hole 14c provided in the base plate 14 and protruding therefrom.
The boss is held on the base plate 14 by a retaining ring RL provided in the groove.

[0098] The gear 142 has a female screw portion 142a on the inner side with which the screw portion of the screw shaft 144 meshes. The screw shaft 144 is connected to the pinion gear 1
38 and an axis of the screw shaft 122 so as to be parallel to each other.

The screw shaft 144 and the female screw portion 142a are screws having the same pitch and the same phase as the screw shaft 122 and the female screw portion of the composite rotating member 140.

A tension coil spring 1 is provided between one end of the screw shaft 144 and the recording head support member 80B.
46 are provided. Thus, the screw shaft 144 and the recording head support member 80B are urged to attract each other by the urging force of the tension coil spring 146 acting in the direction indicated by the arrow. Therefore, the screw shaft 144 is urged against the gear 42 so that backlash between them is reduced. Further, since the height of the tension coil spring 146 does not change, the tension coil spring 146 is urged with a constant urging force regardless of the position where the recording head is moved up and down.

Further, the screw shaft 122 is urged against the composite rotating member 140 by the urging force of the tension coil spring 146 acting in the direction indicated by the arrow.

Accordingly, the flank of the screw of the screw shaft 122 provided on the recording head support member 80B is:
The play flank between the mating compound pivot member 140 and the internal thread flank of the three pulleys, the so-called backlash, reduces the screw flank of the screw shaft 122 to the compound pivot member 140 and the three pulleys. Abut against the flank of the internal thread of the female screw.

As a result, the same operation and effect as in the above-described example can be obtained.

In FIG. 11, the vertical axis represents the biasing force Q of the compression coil spring 132 or the tension coil spring 146, and the horizontal axis represents the movement amount ΔH of the recording head support member.
The relationship between the urging force Q of the compression coil spring 132 or the tension coil spring 146 and the movement amount ΔH is shown.

For example, in the case of a lifting / lowering device having a configuration in which the deflection of the coil spring for urging the backlash is reduced in accordance with the amount of movement of the recording head support member, the recording head It increases in proportion to the amount of movement of the support member.

The biasing force of the spring members 30A and 30B shown in FIG. 3 is macroscopically constant within a predetermined range of the pull-out amount λ, as shown in FIG. Since the outer diameters of the spring members 30A and 30B in FIG. 3 change in accordance with λ, when viewed microscopically, they increase slightly but in proportion to the amount of movement of the recording head support member as shown by the characteristic line Lx in FIG. May be.

On the other hand, in the case of the biasing force Q of the compression coil spring 132 or the extension coil spring 146, there is no possibility that the bending amount and the outer diameter of the compression coil spring 132 or the extension coil spring 146 change, and therefore, the biasing force Q is set as shown in FIG.
Is maintained at the predetermined value Qo without being affected by the movement amount ΔH.

In the example described above, the biasing mechanism uses a coil spring as the elastic member.
The present invention is not limited to this example, and other materials having an elastic force, such as a rubber material and a plastic material, may be used.

[0109]

As is apparent from the above description, according to the recording head lifting apparatus and the recording apparatus of the present invention,
Since the recording head support is urged in a predetermined direction, backlash between the components of the elevating mechanism can be eliminated, and the size of the driving motor can be reduced.

Further, since the urging member directly or indirectly urges the screw shaft member or the driving force transmitting member in a predetermined direction, the backlash between the components of the elevating mechanism is reduced. Irrespective of this, it can be removed with a constant urging force.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of a recording head elevating apparatus according to the present invention, together with an ink jet recording apparatus to which the apparatus is applied.

FIG. 2 is a diagram schematically showing a first embodiment of a recording head lifting / lowering apparatus according to the present invention, together with an ink jet recording apparatus to which the apparatus is applied.

FIG. 3 is a perspective view showing a spring member used in the first embodiment of the recording head lifting / lowering device according to the present invention.

FIG. 4 is a characteristic diagram used to explain the operation of the spring member shown in FIG. 3;

FIG. 5 is a perspective view showing a second embodiment of a recording head lifting / lowering apparatus according to the present invention, together with an ink jet recording apparatus to which the apparatus is applied.

FIG. 6 is a partial cross-sectional view illustrating a main part of a drive unit including an urging mechanism in a third embodiment of the recording head lifting / lowering device according to the present invention.

FIG. 7 is an exploded perspective view showing a part of components in the example shown in FIG. 6 in an exploded manner.

FIG. 8 is a perspective view showing a third embodiment of a recording head lifting / lowering apparatus according to the present invention, together with an ink jet recording apparatus to which the apparatus is applied.

9 is a cross-sectional view schematically showing a configuration in the example shown in FIG.

FIG. 10 is a partial cross-sectional view showing a main part of a drive unit including another example of an urging mechanism in a third embodiment of the recording head lifting / lowering device according to the present invention.

FIG. 11 is a characteristic diagram used for describing the operation of the spring member shown in FIGS. 6 and 10;

FIGS. 12A and 12B are perspective views, partially cut away, showing the appearance of an example of a printing element substrate included in a printing head and the appearance of another example of a printing element substrate included in a printing head, respectively. FIG.

[Explanation of symbols]

 6Y, 6M, 6C, 6B, 6T Recording head 10B, 50, 80B Recording head support member 22, 122, 144 Screw shaft 24, 150 Pulley 30A, 30B Spring member 28, 128 Timing belt 36, 136 Stepping motor 92 Recording element substrate 124 Spring holding member 130, 140 Composite rotating member 132 Compression coil spring 146 Tension coil spring

Continued on the front page F-term (reference) 2C056 FA03 FA13 HA07 HA11 JA04 JA17 JB04 JB08

Claims (20)

[Claims] A recording head supporting section for supporting a recording head for discharging a liquid and performing a recording operation on a recording surface of a recording medium; and a reciprocating movement of the recording head supporting section provided on the recording head supporting section. A driving force transmitting portion to which a driving force is transmitted; a driving force transmitting portion that transmits a driving force that is engaged with and supplied to the driving force transmitting portion via a tooth portion to the driving force transmitting portion; A driving force supply unit connected to a driving force transmission unit for supplying driving force to the driving force transmission unit; and a biasing member configured to bias the recording head support unit in a predetermined direction. Elevating device for recording head. 2. The print head supporter according to claim 1, wherein the biasing member is configured to remove the play of the tooth portion between the drive power transmission unit and the drive force transmission unit. 2. The apparatus according to claim 1, wherein the recording head is biased in one direction with a biasing force greater than the weight of the recording head. 3. The apparatus according to claim 1, wherein the urging member always urges the recording head support in one direction with a constant urging force. 4. The apparatus according to claim 1, wherein said urging member comprises a plurality of spring members. 5. The apparatus according to claim 1, wherein the urging member urges the recording head support in a direction opposite to a direction of its own weight. 6. The driving force transmission unit includes a screw shaft provided on the recording head support unit and extending along a moving direction of the recording head support unit, and the driving force transmission unit meshes with the screw shaft. 2. The apparatus according to claim 1, further comprising a pulley having a female screw hole. 7. The driving force transmission portion includes a rack portion provided on the recording head support portion and extending along a moving direction of the recording head support portion, and the driving force transmission portion meshes with the rack portion. 2. The apparatus according to claim 1, further comprising a pinion gear. 8. The printhead supporter is disposed so as to be able to reciprocate relatively to a recovery processing unit that performs wiping on the printhead so as to maintain normal printing operation of the printhead. The recording head lifting / lowering device according to claim 1, wherein: 9. A recording head supporting portion for supporting a recording head that performs a recording operation on a recording surface of a recording medium, and a first screw portion provided on the recording head supporting portion, wherein the first screw portion moves the recording head supporting portion. A screw shaft member formed along a direction, and a second screw portion fitted to a first screw portion of the screw shaft member, and a driving force transmission for transmitting a supplied driving force to the screw shaft member. A member, a driving force supply unit connected to the driving force transmitting member to supply a driving force, and an urging member for directly or indirectly urging the screw shaft member or the driving force transmitting member in a predetermined direction. A recording head lifting / lowering device comprising: 10. The screw shaft member or the drive unit for removing play between the first screw portion of the screw shaft member and the second screw portion of the driving force transmitting member. The apparatus according to claim 9, wherein the force transmitting member is directly or indirectly biased in one direction. 11. The apparatus according to claim 9, wherein said urging member includes an elastic member. 12. The recording head support section is disposed so as to be able to reciprocate relative to a recovery processing unit that performs a recovery process on the recording head so as to maintain a normal recording operation of the recording head. 10. The apparatus for lifting a recording head according to claim 9, wherein: 13. A recording head supporting portion for supporting a recording head that performs a recording operation on a recording surface of a recording medium; and a first screw portion provided on the recording head supporting portion, wherein a first screw portion moves the recording head supporting portion. A first screw shaft member formed along the direction, and a second screw portion fitted to a first screw portion of the first screw shaft member, the driving force supplied to the first screw shaft member being changed to the first screw shaft member. A first driving force transmitting member for transmitting to the screw shaft member; a second screw shaft member having a third screw portion formed along a moving direction of the recording head support portion; and the second screw shaft. The second screw shaft member has a fourth screw portion fitted to the third screw portion of the member, and supplies the supplied driving force in the same direction as the driving force transmitting direction of the first driving force transmitting member. A second driving force transmitting member for transmitting to the first driving force transmitting member and the second driving force transmitting member; A driving force supply unit connected to a power transmission member for supplying a driving force, disposed between the second screw shaft member and the recording head support unit, the first screw shaft member or the first drive unit; And a biasing member for biasing the force transmitting member in one direction. 14. A biasing member is disposed between the second screw shaft member and the recording head support, and at least a first screw portion of the first screw shaft member and the first drive. The first screw shaft member or the first driving force transmitting member is biased in one direction so as to eliminate play between the force transmitting member and the second screw portion. Item 14. The recording head elevating device according to Item 13. 15. A recording head that discharges a liquid to perform a recording operation on a recording surface of a recording medium, a recording head support that supports the recording head, and the recording head support provided on the recording head support. Receiving a driving force for transmitting the driving force for reciprocating the driving force, and a driving force for transmitting the driving force supplied to the driving force transmitting portion by being engaged with the driving force receiving portion via the tooth portion to the driving force transmitting portion. A transmission unit; a driving force supply unit connected to the driving force transmission unit to supply driving force to the driving force transmission unit; and a biasing member configured to bias the recording head support unit in a predetermined direction. A recording device configured as: 16. A recording head that discharges a liquid to perform a recording operation on a recording surface of a recording medium, a recording head support that supports the recording head, and a first screw that is provided on the recording head support. A screw shaft member formed along the moving direction of the recording head support portion; and a second screw portion fitted to a first screw portion of the screw shaft member. A driving force transmitting member for transmitting a driving force to the screw shaft member; a driving force supplying unit connected to the driving force transmitting member for supplying a driving force; and directly or indirectly determining the screw shaft member or the driving force transmitting member. And a biasing member for biasing in a direction. 17. A recording head that discharges a liquid to perform a recording operation on a recording surface of a recording medium, a recording head support that supports the recording head, and a first screw provided on the recording head support. A first screw shaft member formed along a moving direction of the recording head support portion, and a second screw portion fitted to a first screw portion of the first screw shaft member. A first driving force transmitting member for transmitting the applied driving force to the first screw shaft member; and a second screw shaft having a third screw portion formed along the moving direction of the recording head supporting portion. A driving force to be supplied having the fourth screw portion fitted to the third screw portion of the second screw shaft member and having the same driving direction as the driving force transmitting direction of the first driving force transmitting member; A second driving force transmitting member that transmits the driving force to the second screw shaft member in the direction; A driving force supply unit connected to a driving force transmission member and the second driving force transmission member for supplying a driving force; a driving force supply unit disposed between the second screw shaft member and the recording head support unit; And a biasing member for biasing the screw shaft member or the first driving force transmitting member in one direction. 18. The recording apparatus according to claim 15, wherein a plurality of the recording heads are arranged from an upstream side to a downstream side in a conveyance path of the recording medium. 19. The recording apparatus according to claim 15, wherein the recording head has a liquid ejection port forming surface on which a plurality of liquid ejection ports are formed corresponding to the entire recording surface of the recording medium. . 20. The recording apparatus according to claim 19, wherein the recording head has an electrothermal transducer for heating the liquid and discharging the liquid from a liquid discharge port.