Patent Application
20100236435
1. Field of the Invention
The present invention relates to a drum-changeable device for a printer and, more particularly, to a drum-changeable device for a printer for selecting a suitable drum according to different kinds of material of printing articles.
2. Description of the Prior Art
Conventionally, drums are used in printers for moving printing articles forward by rotating the drums. Generally, the drums are covered with etched iron sheets and the printing articles will be moved forward by means of the friction force produced between the etched iron sheets and the contact surface of the articles.
As shown in
The drums 41 with protrusions 42 that are covered by etched iron sheets have better effects for moving articles of soft material forward, such as papers. In other words, sufficient friction force can be produced between the etched iron sheets and the articles of soft material to move forward the articles of soft material. However, the drums 41 having protrusions 42 covered by etched iron sheets are not suitable for some other articles of different kinds of material, such as hard material. Therefore, the drums 41 having protrusions 42 covered by etched iron sheets have limited effects when used for moving printing articles of hard material.
Etched granules on the etched iron sheets are unable to be engaged with the contact surface of printing articles of hard material, such as glasses and acrylic boards, and slip phenomenon will occur between the etched iron sheets and the bottom of the printing articles of hard material when these printing articles are moved by a drum 41 having protrusions 42 covered by etched iron sheets. Accordingly, the printing articles of hard material will fail to be moved in the continuing printing procedure. In this case, the drum 41 having protrusions 42 covered by soft material can be used to move forward the printing articles of hard material successfully.
Moreover, due to the limitation of the structure of current printers, it will be difficult to change drums 41 having protrusions 42 covered by different kinds of material when printing articles of different kinds of material are to be printed, such as printing articles of soft material or of hard material. Under this situation, it is inconvenient and not economic because considerable time and labor power have to be wasted.
In order to solve the problems mentioned above to provide a drum-changeable device for a printer to select a suitable drum conveniently according to the kind of material of printing articles, inventor had the motive to study and develop the present invention after hard research.
The main object of the present invention is to provide a drum-changeable device for a printer to select a suitable drum conveniently according to different kinds of material of printing articles.
In order to achieve the above object, the present invention provides a drum-changeable device for a printer. The drum-changeable device comprises a plurality of drums and a switch device. The drums are disposed under the work surface of a printer. Each drum has a plurality of protrusions covered by the same kind of material and the protrusions of different drum are covered by different kind of material for moving forward printing articles of different kinds of material. The switch device is connected with the drums for moving a suitable drum toward the work surface of the printer according to the kind of material of printing articles.
The following detailed description, given by way of examples and not intended to limit the invention solely to the embodiments described herein, will best be understood in conjunction with the accompanying drawings.
The present invention discloses a drum-changeable device for a printer comprising a plurality of drums 10,12 and a switch device 20. The plural drums 10,12 are disposed under the work surface 30 of a printer. Each drum 10,12 has a plurality of protrusions 104, 124 covered by the same kind of material and the protrusions 104, 124 of different drum 10,12 are covered by different kind of material for moving forward printing articles of different kinds of material. The switch device 20 connected with the drums 10,12 are used for moving a suitable drum 10,12 toward the work surface 30 of the printer according to the different kinds of material of the printing articles.
As shown in
In the first embodiment of the present invention, the drums 10,12 are disposed under the work surface 30 of the printer. Each drum 10,12 has an axial rod 102, 122 and a plurality of protrusions 104, 124. The protrusions 124 of one drum 12 are covered by soft material that is suitable for moving the printing articles of hard material while the protrusions 104 of the other drum 10 are covered by hard material that is suitable for moving the printing articles of soft material. The soft material used for covering the protrusions 124 of the drum 12 can be rubber or other similar kinds of material. The hard material used for covering the protrusions 104 of the drum 10 can be metal repousse or other similar kinds of material. Besides, openings 32 are provided on the work surface 30 and the protrusions 104, 124 protrude from the openings 32 on the work surface 30.
The switch device 20 includes a worm rod 22 and a worm gear 24. The worm gear 24 is connected with the worm rod 22 and drums 10, 12 respectively. In the first embodiment, the worm gear 24 has two holes 240 located near its center point for inserting axial rods 102, 122 of the drums 10, 12 respectively. Therefore, the worm gear 24 will be rotated by means of turning the worm rod 22 clockwise or counterclockwise and a suitable drum 10, 12 can be moved toward the work surface 30 of the printer by the rotation of the worm gear 24. By this way, the protrusions of the suitable drum 10, 12 will protrude out of the work surface 30 via the openings 32 for moving forward printing articles.
Accordingly, as disclosed in the above description and attached drawings, the present invention can provide a drum-changeable device for a printer to select a suitable drum efficiently according to different kinds of material of printing articles. It is new and can be put into industrial use.
It should be understood that different modifications and variations could be made from the disclosures of the present invention by the people familiar in the art, which should be deemed without departing the spirit of the present invention.
