JPH0568988U - Print medium transport device - Google Patents

Abstract

(57) [Abstract] [Purpose] In a print medium carrying device for carrying print media of various thicknesses, even when a thick print medium enters, the power is reliably transmitted to both shafts of the carry roller and the print medium is conveyed. To ensure that they are transported accurately. [Structure] A drive gear 12 to which a rotational force of a carry motor 5 is transmitted on a support shaft 8 of a swing lever 7 which supports a movable roller 2.
And the driven gear 11 is provided on the shaft of the movable roller 2, and the drive gear 12 is directly meshed with the driven gear 11 or indirectly meshed via the toothed belt 13.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a print medium carrying device used in a printer, and more particularly, to a print medium carrying device for carrying print media such as passbooks and notebooks that are relatively thick and have different thicknesses.

[0002]

[Prior Art]

 In printers that print passbooks, notebooks, etc., it is necessary to carry print media of different thicknesses depending on the type of print media and even on the same media depending on the print page. FIG. 1 is a side view of a conventional print medium carrying device applied to the printer described above, and FIG. 2 is a front view of the same. In FIGS. 1 and 2, 1 is a fixed roller whose shaft is fixed, and 2 is a movable roller which abuts against the fixed roller 1. These both constitute a conveying roller 3, and the conveying roller 3 is an upper and lower guide plate. Are arranged at appropriate places on the transport path 4 consisting of.

Reference numeral 5 denotes a carry motor, and the belt 6 hung between the pulley of the carry motor 5 and the pulley of the fixed roller 1 transmits the rotational force of the carry motor 5 to the fixed roller 1. . Reference numeral 7 denotes a hook-shaped rocking lever, which rocks around a support shaft 8, and the movable roller 2 is attached to the tip thereof. A coil spring 9 is provided at the lower end of the rocking lever 7 for urging in the pulling direction, and the action of the coil spring 9 urges the movable roller 2 in a clockwise direction to press it against the fixed roller 1.

In this state, when the print medium is inserted or conveyed from the upstream side of the conveying path 4 and is gripped in the nip of the conveying roller 3, the movable roller 2 moves to the coil spring 9 depending on its thickness. It slightly swings counterclockwise against the pulling force. As shown in FIG. 2, a plurality of fixed rollers 1 and movable rollers 2 (two in this example) are provided in pairs on each shaft.

By the way, in order to ensure the conveyance of a relatively thick print medium, conventionally, both shafts of a fixed roller 1 and a movable roller 2 which are provided on both sides of a conveyance surface are forcibly driven by a conveyance motor 5. . Specifically, as shown in FIG. 2, by engaging the gears 10 and 11 provided at one end of the shaft of the fixed roller 1 and one end of the shaft of the movable roller 2, respectively, the driving force on the fixed roller 1 side is changed. It was transmitted to the 2 side.

[0006]

[Problems to be solved by the device]

 In such a conventional device, when a thin print medium enters the nip portion of the transport roller, the gears are surely meshed with each other so that the print medium can be accurately transported, but the thick print medium is thick. When the medium enters, the backlash between the gears 10 and 11 becomes large, and in extreme cases, the meshing of the gears is released, so that there is a problem that the conveyance becomes impossible.

An object of the present invention is to provide a print medium transporting device capable of transporting print media having different thicknesses, and reliably transmits power to both shafts of a transport roller even when a thick print medium enters. The purpose is to be able to.

[0008]

[Means for Solving the Problems]

 In the present invention, in order to achieve the above object, a drive gear for transmitting the rotational force of a conveying motor is provided on a support shaft of a swing lever that supports a movable roller, and a driven gear on the shaft of the movable roller. Is provided, and the drive gear is directly meshed with the driven gear or indirectly meshed via a toothed belt.

[0009]

[Action]

 The drive gear to which the rotational force from the transport motor is transmitted is provided on the pivot of the rocking lever, and its position does not change even if the movable roller is displaced according to the thickness of the print medium. The meshing with the driven gear is always constant, and the rotational force of the carry motor can always be reliably transmitted to the movable roller via the driven gear.

[0010]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. It should be noted that members that are the same as or can be regarded as the same as those in the conventional example are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 3 and FIG. 4 are a side view and a front view of the print medium carrying device according to the first embodiment, in which a drive gear 12 is provided at one end of the support shaft 8 and one end of the movable roller 2 is provided. The driven gear 11 is engaged. A belt 6 is stretched between pulleys provided on the shaft of the carry motor 5, the shaft of the fixed roller 1, and the support shaft 8.

The rotational force of the carry motor 5 is transmitted to the fixed roller 1 and the drive gear 12 by this belt 6. Since the driven gear 11 meshes with the drive gear 12 as described above, the driving force is also transmitted to the movable roller 2 via the driven gear 11.

In such a configuration, when the print medium enters between the fixed roller 1 and the movable roller 2, the movable roller 2 slightly oscillates counterclockwise according to its thickness, as described above. A driven gear 11 on the same axis as the movable roller 2 also swings around the support shaft 8 while maintaining proper meshing with the drive gear 12.

However, since the drive gear 12 to which the rotational force of the carry motor 5 is transmitted is fixed on the support shaft 8, the meshing with the driven gear 11 is always constant regardless of the fluctuation of the print medium thickness. Therefore, the rotational force of the carry motor 5 can always be accurately transmitted to the movable roller 2 via the belt 6, the drive gear 12, and the driven gear 11.

FIG. 5 is a simplified side view of the print medium carrying device according to the second embodiment. In the first embodiment shown in FIGS. 3 and 4, the driven gear 11 and the drive gear 12 are directly meshed with each other, but in this embodiment, both are indirectly meshed via the toothed belt 13. Also in this embodiment, the position of the drive gear 12 does not change even if the position of the movable roller 2 and hence the driven gear 11 is displaced, so that the meshing with the driven gear 11 is always constant.

The rotation force of the conveyance motor 5 is not limited to the mechanism in which the rotation force of the conveyance motor 5 is transmitted to both the fixed roller 1 and the movable roller 2 by the belt 6, and the rotation force of the conveyance motor 5 can be changed as shown in FIGS. It is also possible to adopt a mechanism in which gears are provided directly to the fixed roller 1 side, and gears that engage with the fixed roller shaft and the support shaft 8 are provided, and the drive gear 12 and thus the movable roller 2 are driven by this gear train.

[0017]

[Effect of the device]

 As described above, according to the present invention, a drive gear that meshes with a movable roller that is displaced around a pivot shaft of a swing lever according to the thickness of a print medium that enters a conveying roller and a driven roller that is coaxial with the movable roller. Since it is provided on the support shaft, the meshing with the driven gear is always constant regardless of the variation of the print medium thickness, and the thick print medium can be accurately conveyed.

[Brief description of drawings]

FIG. 1 is a side view of a print medium conveying device according to a conventional example.

FIG. 2 is a front view of a print medium carrying device according to a conventional example.

FIG. 3 is a side view of the print medium transport device according to the first embodiment of the present invention.

FIG. 4 is a front view of the print medium conveying device according to the first embodiment of the present invention.

FIG. 5 is a simplified side view of a print medium carrying device according to a second embodiment of the present invention.

[Explanation of symbols]

 1 Fixed Roller 2 Movable Roller 3 Conveying Roller 7 Swing Lever 8 Spindle 11 Driven Gear 12 Drive Gear 13 Toothed Belt

Claims (1)

[Scope of utility model registration request] 1. A printing medium carrying device for carrying a printing medium having various thicknesses by a carrying roller composed of a fixed roller and a movable roller whose gap between the fixed roller and the printing medium changes depending on the thickness of the printing medium. A drive gear for transmitting the rotational force of the carry motor is provided on a support shaft of a swing lever that supports the roller, and a driven gear is provided on the shaft of the movable roller, and the drive gear is directly meshed with the driven gear. A print medium conveying device characterized by being indirectly meshed via a toothed belt.