Electrical knife sharpening device

Abstract

A knife sharpening device includes a base with a motor and a gear reduction assembly connected thereto. A main shaft is connected to the gear reduction assembly and two grinding disks are mounted on the main shaft. A separation tube is mounted on the main shaft and located between the two grinding disks. Each grinding disk has a spring urging thereto so as to prevent the grinding disks from shaking. A cover is mounted to the base and has straight slots each of which is in communication between two openings. Each slot includes two narrow ends which communicate with the two openings so that the blades of knives are inserted perpendicularly in the slots and the cutting edge is slightly clamped by the narrow ends.

Description

FIELD OF THE INVENTION

[0001] This is a Continuation-In-Part application for applicant's former application with the application Ser. No. 09/905,805 having the same title as the application.

BACKGROUND OF THE INVENTION

[0002] A conventional electrical knife sharpening device generally includes a motor which drives one or two grinding disks directly so that the rotational speed of the grinding disks is so high that could damage the edges of blades of the knives. Besides, once the grinding disks are not installed at their proper positions, the high rotational speed of the grinding disks will make the grinding disks tremble and generate noise.

[0003] U.S. Pat. No. 6,012,971 discloses a sharpening apparatus that has two pairs of inclined slots for being received the blades which are sharpened by the abrasive material. However, the blades have to be inserted into the slots at an angle relative to the top of the casing of the apparatus and this is not convenient for the users to operate. In other words, the users have to carefully insert the blades in the grooves otherwise the cutting edges may be hit by the casing of the apparatus. U.S. Pat. No. 5,245,789 discloses another knife sharpener which has a slot that allows the knife to be perpendicularly inserted. Nevertheless, the slot includes two dead ends which could touch and damage the cutting edge of the knife to be sharpened.

SUMMARY OF THE INVENTION

[0004] In accordance with one aspect of the present invention, there is provided an electrical knife sharpening device which comprises a base and a motor is connected to the base. A gear reduction assembly is connected to an output shaft of the motor and a main shaft respectively. Two grinding disks are mounted to the main shaft and a separation tube is mounted to the main shaft and located between the two grinding disks. Two springs are mounted on the main shaft and push the two grinding disks toward the separation tube. A cover is mounted to the base and has slots defined therethrough to access the grinding disks. Each slot allows the blade

[0005] The primary object of the present invention is to provide a knife sharpening device wherein each slot is a straight slot and includes two narrow ends which are in communication to two respective openings such that the cutting edge of the blade is slightly clamped by the narrow ends and not be damaged.

[0006] Another object of the present invention is to provide a knife sharpening device that has a gear reduction assembly connected to the motor and the grinding disks are pushed by two springs so as to be maintained in a correct position.

[0007] 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

[0008] FIG. 1 is an exploded view to show a knife sharpening device of the present invention;

[0009] FIG. 2 is a perspective view to show the knife sharpening device of the present invention;

[0010] FIG. 3 is a top view of the knife sharpening device of the present invention;

[0011] FIG. 4 is a side view to show the knife sharpening device of the present invention;

[0012] FIG. 5 shows the other side of the knife sharpening device of the present invention;

[0013] FIG. 6 shows the slots are straight in the mask;

[0014] FIG. 7 is a cross sectional view to show the knife sharpening device of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0015] Referring to FIGS. 1 to 3, the knife sharpening device of the present invention comprises a base 10 having a plurality of separation plates and a plurality of recesses 11, 12, 13 and 14 are defined in these separation plates so that a motor 20, a gear reduction assembly 30 and two grinding disks 54 are installed in the recesses 11, 12, 13 and 14. A cover 60 is mounted to the top of the base 10 by extending bolts 61 through tubes 15 in the base 10 and engaged with the cover 60. An opening is defined in a top of the cover 60 and has two positions 62 for receiving the grinding disks 54. A mask 70 is connected to the opening of the cover 60 by screws 71 and a plurality of slots 72 are defined through the mask 70 and each slot 72 is a straight slot 72 as shown in FIG. 6. Further referring to FIGS. 4 and 5, each slot 72 is in communication between a circular opening 721 and a rectangular opening 722. The two openings 721, 722 communicate with the slot 72 such that when the blade 81 of a knife 80 is inserted in the slot 72, the cutting edge is slightly clamped by the two narrow ends of the slot 72 and will not be hit by the mask 70 because the two openings 721, 722 receive the cutting edge even if the cutting edge penetrates through the two narrow ends.

[0016] The motor 20 has an output shaft 21 to which a ventilation fan 22 and a gear reduction assembly 30 are respectively connected to two ends of the output shaft 21. A main shaft 40 is connected to a central rod 31 for connecting the gears of the gear reduction assembly 30. Two grinding disks 54 are mounted to the main shaft 40 and a separation tube 55 is mounted to the main shaft 40 and located between the two grinding disks 54. Two springs 53 are mounted on the main shaft 40 and push the two grinding disks 54 toward the separation tube 55. Two grooves 41 are defined in the main shaft 40 and two retaining washers 51 are mounted to the main shaft 40 and contact an end of each of the springs 53. Two C-shaped clips 52 are engaged with the two grooves 41 to keep the retaining washers 51 in position. A cap 56 is mounted to an end of the main shaft 40.

[0017] Referring to FIG. 7, the grinding disks 54 are pushed by the springs 53 so that the grinding disks 54 can be maintained toward the separation tube 55. The speed of the grinding disks 54 is properly controlled because of the gear reduction assembly 30. A grinding surface of each of the grinding disks 54 is located at angle relative to the slot 72 so that when the blade 81 is inserted in the slot 72 in perpendicular to a horizontal plane, the grinding surface of the grinding disk 54 sharpens the blade 81 at a correct angle.

[0018] Because the slots 72 are straight, the users need not to tilt the blade 81 before being inserted into the slot 72 and the users just insert the blade 81 perpendicularly into the slot 72. This is convenient for the users. Besides, the cutting edge of the blade 81 will not contact the mask 70 so that the cutting edge is not damaged during operation.

[0019] 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 electrical knife sharpening device comprising:

a base;

a motor connected to the base and a gear reduction assembly connected to an output shaft of the motor, a main shaft connected to the gear reduction assembly, two grinding disks mounted to the main shaft and a separation tube mounted to the main shaft and located between the two grinding disks, two springs mounted on the main shaft and pushing the two grinding disks toward the separation tube, and

a cover mounted to the base and having straight slots defined therethrough to access the grinding disks, a grinding surface of each of the grinding disks being located at an angle relative to the slot corresponding thereto.

2. The knife sharpening device as claimed in claim 1 wherein each straight slot is in communication between two openings.

3. The knife sharpening device as claimed in claim 2 wherein each straight slot includes two narrow ends which communicate with the two openings respectively.