Knife sharpener

Abstract

An electric sharpener includes a body having a reception area for receiving a driving device, and a sharpening area in which a gear set is located which is connected with the driving device. A shaft is located in the sharpening area and connected to the gear set. A rough sharpening set connected to the shaft and has a first spring unit. A fine sharpening set is connected to the shaft and has a second spring unit. The first and second spring sets have different spring forces applied to the rough sharpening set and the fine sharpening set.

Description

FIELD OF THE INVENTION

The present invention relates to an electric sharpener, and more particularly, to an electric sharpener having two sets of girding disks with different spring units.

BACKGROUND OF THE INVENTION

A conventional electric sharpener is used to sharpen knives or scissors and generally includes a grinding wheel which is driven by a motor and the users press the blade of the knife on the rotating grinding wheel to sharpen it. Some of the conventional sharpeners have two grinding wheels for different purposes of sharpening, such as rough sharpening and fine sharpening. The two sharpening wheels are connected to the same shaft so that they are rotated at the same speed, however, the requirements for the two different types of sharpening are not the same. The usual way is to reduce the speed of the motor to have a compromise. If the speed is adjusted to a high speed, the users have to have certain skill otherwise the knife may be damaged. The electric power only provides the rotation of the grinding wheels and cannot adjust the pressure that the blade is pressed on the grinding wheels. This restricts the result of sharpening because most of the users do not have the skill to properly operate the knife relative to the grinding wheels.

The present invention intends to provide an electric sharpener which includes two spring units for the rough sharpening set and the fine sharpening set respectively so as to meet different requirements of the two different sharpening actions.

SUMMARY OF THE INVENTION

The present invention relates to an electric sharpener which comprises a body having a reception area and a sharpening area, wherein a driving device is located in the reception area and connected to a gear set located in the sharpening area. A shaft is located in the sharpening area and connected to the gear set. A rough sharpening set is connected to the shaft and located beside the gear set. The rough sharpening set has a first spring unit. A fine sharpening set is connected to the shaft and located beside the rough sharpening set. The fine sharpening set has a second spring unit. The first and second spring sets apply different spring forces to the rough sharpening set and the fine sharpening set so as to achieve different purposes of sharpening.

A first fixing ring is located between the first left grinding disk and the first right grinding disk, and a second fixing ring is located between the second left grinding disk and the second right grinding disk. By the two fixing rings, the knife can be precisely inserted into the two sharpening units and are sharpened steadily.

The primary object of the present invention is to provide an electric sharpener which includes two sharpening units which are cooperated with different spring units so as to provide proper spring forces to the two sharpening units.

Another object of the present invention is to provide an electric sharpener wherein the two spring units have different elasticity coefficients so that the axial pressures to the two sharpening units are different.

Yet another object of the present invention is to provide an electric sharpener wherein each of the two sharpening units has a positioning ring which position the two sharpening units firmly on the shaft so that the sharpening action is operated in a stable status.

The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the front view of the electric sharpener of the present invention;

FIG. 2 shows the driving device, the gear set, the shaft and the two sharpening sets of the electric sharpener of the present invention;

FIG. 3 shows the driving device, the gear set, the shaft and the detail structure of two sharpening sets of the electric sharpener of the present invention;

FIG. 4 shows that a knife is sharpened by the rough sharpening set of the electric sharpener of the present invention, and

FIG. 5 shows that a knife is sharpened by the fine sharpening set of the electric sharpener of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 to 3, the electric sharpener 10 of the present invention comprises a body 10 which includes a reception area 11 and a sharpening area 12 which is located beside the reception area 11. A driving device 20 is located in the reception area 11 and includes an output shaft which is connected with a first gear of a gear set 30 located in the sharpening area 12. A second gear is engaged with the first gear and connected to a shaft 40 which is located in the sharpening area 12. A rough sharpening set 50 is connected to the shaft 40 and located beside the gear set 30. The rough sharpening set 50 has a first spring unit 51. A fine sharpening set 60 is connected to the shaft 40 and located beside the rough sharpening set 50. In other words, the rough sharpening set 50 is located between the fine sharpening set 60 and the gear set 30. The fine sharpening set 60 has a second spring unit 61. The first and second spring sets 51, 61 have different spring forces applied to the sharpening set 50 and the fine sharpening set 60.

The sharpening area 12 comprises a first slot 121 and a second slot 122, the rough sharpening set 50 is located beneath the first slot 121 and the fine sharpening set 60 is located beneath the second slot 122. Each of the first and second slots 121, 122 communicates with a groove 123.

The first spring unit 51 comprises a first left spring 511 and a first right spring 512, and the rough sharpening set 50 comprises a first sharpening unit 52 which is located between the first left spring 511 and the first right spring 512. The first sharpening unit 52 comprises a first left grinding disk 521 and a first right grinding disk 522. The first left grinding disk 521 contacts the first left spring 511 and the first right grinding disk 522 contacts the first right spring 512. A first fixing ring 523 is located between the first left grinding disk 521 and the first right grinding disk 522. A first positioning plate 524 is located in the first right grinding disk 522 and the first right spring 512 contacts the first positioning plate 524. The first left grinding disk 521 and the first right grinding disk 522 are two circular plates. The first right grinding disk 522 is inserted into a recessed area of the first left grinding disk 521.

The second spring unit 61 comprises a second left spring 611 and a second right spring 612. The fine sharpening set 60 comprises a second sharpening unit 62 which is located between the second left spring 611 and the second right spring 612. The second sharpening unit 62 comprises a second left grinding disk 621 and a second right grinding disk 622. The second left grinding disk 621 contacts the second left spring 611 and the second right grinding disk 622 contacts the second right spring 612. A second fixing ring 623 is located between the second left grinding disk 621 and the second right grinding disk 622. A second positioning plate 624 is located in the second right grinding disk 622 and the second right spring 612 contacts the second positioning plate 624. The second left grinding disk 621 and the second right grinding disk 622 are two circular plates. The second right grinding disk 622 is inserted into a recessed area of the second left grinding disk 621.

The shaft 40 has a first flange 70, a second flange 80 and a third flange 90 mounted thereto, wherein the first flange 70 is located and in contact between the first spring unit 51 and the second spring unit 61. The second flange 80 is located such that the first spring unit 51 contacts the second flange 80 and the third flange 90 is located such that the second spring unit 61 contacts the third flange 90. The first spring unit 51 and the second spring unit 61 have different elasticity coefficients so as to provide different forces to the rough and fine sharpening sets 50, 60 to meet different types of sharpening requirements.

Referring to FIGS. 4 and 5, when sharpening a knife “K”, the blade “K1” of knife “K” is first inserted into the first slot 121 of the rough sharpening set 50, the first slot 121 guides the blade “K1” and two sides of the blade “K1” are in contact with the first left grinding disk 521 and the first right grinding disk 522. The driving device 20 drives the gear set 30 and the shaft 40, the first sharpening unit 52 is rotated with the shaft 40 so that the first left grinding disk 521 and the first right grinding disk 522 sharpen the blade “K1”. The user presses the knife “K” to let the first left grinding disk 521 and the first right grinding disk 522 sharpen the blade “K1” continuously. Because the first spring unit 51 has larger spring force, so that the rough sharpening set 50 provide intensive sharpening feature to the blade “K1”. The blade “K1” enters into the groove 123 of the first slot 121 and cannot be inserted further so as to avoid the blade “K1” from being in contact with the shaft 40 and damaged.

After the rough sharpening is completed, the knife “K” has surplus material on the sharpened area and is then sharpened in the fine sharpening set 60. The blade “K1” of knife “K” is inserted into the second slot 122 and two sides of the blade “K1” are in contact with the second left grinding disk 621 and the second right grinding disk 622. The driving device 20 drives the gear set 30 and the shaft 40, the second sharpening unit 62 is rotated with the shaft 40 so that the second left grinding disk 621 and the second right grinding disk 622 further sharpen the blade “K1”. Again, the user presses the knife “K” to let the second left grinding disk 621 and the second right grinding disk 622 sharpen the blade “K1” continuously. Because the second spring unit 61 has smaller spring force than the first spring unit 51, so that the fine sharpening set 60 provides fine sharpening feature to the blade “K1”. The blade “K1” enters into the groove 123 of the second slot 122 and cannot be inserted further so as to avoid the blade “K1” from being in contact with the shaft 40 and damaged.

Because the first and second spring units 51, 61 have different spring forces so that the rough and fine sharpening sets 50, 60 have different axial pressure to sharpen the knife “K” to obtain different sharpening results.

The first and second fixing rings 523, 623 ensure that the rough and fine sharpening sets 50, 60 are properly installed on the shaft 40 so that the knife “K” can be sharpened in a stable status.

While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.

Claims

1. An electric sharpener comprising:

a body having a reception area and a sharpening area;

a driving device located in the reception area;

a gear set located in the sharpening area and close to the reception area, the gear set connected with the driving device;

a shaft located in the sharpening area and connected to the gear set;

a rough sharpening set connected to the shaft and located beside the gear set, the rough sharpening set having a first spring unit and a first sharpening unit, the first spring unit comprising a first left spring and a first right spring, the first sharpening unit located between the first left spring and the first right spring, the first sharpening unit comprising a first left grinding disk and a first right grinding disk, the first left grinding disk contacting the first left spring and the first right grinding disk contacting the first right spring, a first fixing ring located between the first left grinding disk and the first right grinding disk, a first positioning plate located in the first right grinding disk and the first right spring contacting the first positioning plate, the first left grinding disk and the first right grinding disk being two circular plates, the first right grinding disk being inserted into a recessed area of the first left grinding disk;

a fine sharpening set connected to the shaft and located beside the rough sharpening set, the fine sharpening set having a second spring unit and a second sharpening unit, the second spring unit comprising a second left spring and a second right spring, the second sharpening unit located between the second left spring and the second right spring, the second sharpening unit comprising a second left grinding disk and a second right grinding disk, the second left grinding disk contacting the second left spring and the second right grinding disk contacting the second right spring, a second fixing ring located between the second left grinding disk and the second right grinding disk, a second positioning plate located in the second right grinding disk and the second right spring contacting the second positioning plate, the second left grinding disk and the second right grinding disk being two circular plates, the second right grinding disk being inserted into a recessed area of the second left grinding disk, the first and second spring sets having different spring forces, and

the shaft having a first flange, a second flange and a third flange mounted thereto, the first flange located and in contact between the first spring unit and the second spring unit, the second flange located such that the first spring unit contacts the second flange, the third flange located such that the second spring unit contacts the third flange.

2. The sharpener as claimed in claim 1, wherein the sharpening area comprises a first slot and a second slot, the rough sharpening set is located beneath the first slot and the fine sharpening set is located beneath the second slot.

3. The sharpener as claimed in claim 2, wherein each of the first and second slots communicates with a groove.