Electric pencil sharpener

Abstract

The utility model provides an electric pencil sharpener which comprises a pencil feeding assembly, a center transmission wheel, a knife rest assembly, a transmission assembly, a motor and a power source, the motor is electrically connected with the power source, the motor can provide power for the knife rest assembly, the knife rest assembly can rotate under the driving of the motor, and then the rotating power is transmitted to the center transmission wheel. The center transmission wheel can synchronously rotate with the knife rest assembly and drive at least one part of the pencil feeding assembly to rotate, the pencil feeding assembly comprises a pressing plate and a base, at least one part of the center transmission wheel is contained in a cavity formed between the pressing plate and the base, the pressing plate is provided with a top face restraining piece, and the base is provided with a bottom face restraining piece. The top face restraining piece abuts against the top face of the center transmission wheel, and the bottom face restraining piece abuts against the bottom face of the center transmission wheel, so that when the electric pencil sharpener executes the pencil sharpening action, the center transmission wheel only rotates around the axis direction and does not move up and down in the axis direction.

Description

Technical Field

[0001] This utility model relates to the field of stationery and document parts, and in particular to an electric pencil sharpener. Background Technology

[0002] Pencil sharpeners are a popular tool among students, making pencil sharpening convenient and safe. Electric pencil sharpeners are becoming increasingly popular in homes, schools, and offices due to their convenience and efficiency. An electric pencil sharpener typically consists of a pencil feed assembly, a central drive wheel, and a blade holder assembly. During sharpening, the power transmission in an electric pencil sharpener is generally as follows: the motor generates power, which is then transmitted through the drive assembly to the blade holder assembly, which in turn transmits it to the central drive wheel, which then transmits it to the pencil feed assembly. Finally, the pencil feed assembly automatically moves the pencil forward and backward.

[0003] One existing transmission method involves direct contact between the top surface of the central drive wheel and the outer contour of the worm gear on the rotating wheel, restricting the axial upward movement of the central drive wheel. This structure easily leads to excessively tight or loose meshing between the worm gear and the end gear on the central drive wheel, causing gear damage or excessive noise, severely affecting the lifespan or noise performance of the transmission mechanism. Another commonly used transmission method involves the central drive wheel driving the worm, which in turn drives the rotating wheel. In this structure, because the upper part of the central drive wheel lacks support, the central drive wheel will shift upwards during transmission. Therefore, an additional central drive wheel cover plate is required, which not only complicates the structure and increases assembly difficulty but also significantly increases material and assembly costs.

[0004] There is an urgent need for a center wheel fixing mechanism that is simple in structure and processing, low in cost, reliable and durable in transmission, and long in service life, in order to solve the technical problems of complex structure, short life, high noise and high cost in the current center wheel fixing process of electric pencil sharpeners. Utility Model Content

[0005] The purpose of this utility model is to provide an electric pencil sharpener. The principle and structure of this device are simple, which can effectively reduce the number of parts, reduce assembly difficulty, reduce equipment failure caused by the coordination between parts, and is low in cost, stable and reliable, and has reliable and durable transmission.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] An electric pencil sharpener includes: a pencil feed assembly, a central drive wheel, a blade holder assembly, a motor, and a power supply. The motor is electrically connected to the power supply and provides power to the blade holder assembly. The blade holder assembly rotates under the drive of the motor, transmitting rotational power to the central drive wheel. The central drive wheel rotates synchronously with the blade holder assembly and drives the rotating wheel unit of the pencil feed assembly to rotate. The pencil feed assembly also includes a pressure plate and a base. At least a portion of the central wheel is housed in a cavity formed between the pressure plate and the base. The pressure plate has a top surface constraint, and the base has a bottom surface constraint. The top surface constraint abuts against the top surface of the central drive wheel, and the bottom surface constraint abuts against the bottom surface of the central drive wheel. This ensures that when the electric pencil sharpener performs the pencil sharpening action, the central drive wheel only rotates about its axis and does not move vertically along the axis.

[0008] Furthermore, the pen feed assembly includes two sets of rotary units.

[0009] Furthermore, the pen feed assembly includes a worm gear.

[0010] Furthermore, the two sets of rotating units are arranged parallel to each other and axially symmetrical.

[0011] Furthermore, the rotary wheel unit includes a rotary wheel, a worm gear, and a rotating shaft. The rotary wheel unit is positioned above the central drive wheel along the axial direction, and the worm gear can transmit the rotation of the central drive wheel to the rotary wheel unit.

[0012] Furthermore, the top surface constraint is a slender cylindrical structure, and the axial projection surface of the top surface constraint at the top surface contact point is independent of the axial projection surface of the wheel unit on the top surface and does not interfere with each other.

[0013] Furthermore, the bottom constraint is a protruding rib structure that extends axially upward from the base.

[0014] Furthermore, the rotating unit includes a rotating wheel that clamps the pencil when cutting it; the rotating wheel is made of soft rubber.

[0015] Furthermore, the worm includes spur teeth and helical teeth, the side wall of the central drive wheel includes drive teeth, the rotating wheel and the worm wheel are coaxially arranged, the spur teeth can mesh with the drive teeth, and the helical teeth can mesh with the worm wheel.

[0016] Furthermore, the top surface constraint component is integrated with the pressure plate.

[0017] Furthermore, the bottom constraint component is integrated with the base.

[0018] Furthermore, the electric pencil sharpener also includes a control unit for controlling the start and stop of the motor.

[0019] This utility model provides an electric pencil sharpener, which has the following advantages over the prior art:

[0020] By designing the cover plate structure of the pen inlet mechanism, the central drive wheel can be cleverly constrained, limiting its displacement along the axial direction and ensuring reliable fixation. This saves on product processing, material, and assembly costs, and the overall structure is more compact, stable, and reliable. Attached Figure Description

[0021] The above-described technical content of this utility model and the following detailed embodiments will be better understood when read in conjunction with the accompanying drawings. It should be noted that the drawings are merely examples of the claimed technical solution. In the drawings, the same reference numerals represent the same or similar elements.

[0022] Figure 1 This is a schematic diagram of the exploded view of the pen input component;

[0023] Figure 2 It is a three-dimensional schematic diagram of the front and back of the central drive wheel;

[0024] Figure 3 This is a three-dimensional schematic diagram of the front and back of the pressure plate;

[0025] Figure 4 This is a 3D diagram showing the front and back of the base;

[0026] Figure 5 This is a side view of an electric pencil sharpener;

[0027] Figure 6 yes Figure 5 A schematic cross-sectional view along the AA direction;

[0028] Figure 7 This is a three-dimensional schematic diagram of the assembled pen feed assembly, central drive wheel, and tool holder assembly.

[0029] Figure 8 This is a schematic diagram of the side view after the pen feed assembly, center drive wheel, and tool holder assembly are assembled.

[0030] Figure 9 yes Figure 8 A schematic cross-sectional view along the BB direction;

[0031] Figure 10 This is a top view of the assembled pen feed assembly, center drive wheel, and tool holder assembly.

[0032] Figure 11 This is a schematic diagram of the front view of the pen feed assembly - center drive wheel;

[0033] Figure 12 yes Figure 11 Cross-sectional view diagram in the CC direction

[0034] Figure 13It is the structure of a conventional pencil sharpener's feed assembly;

[0035] Figure 14 It is another type of conventional pencil sharpener's feed assembly structure.

[0036] The reference numerals in the attached figures are explained as follows:

[0037] Motor: 100

[0038] Transmission components: 200

[0039] Tool holder assembly: 300

[0040] Cutting tools: 310

[0041] Tool post drive component: 320

[0042] Center drive wheel: 400; 400a

[0043] Top surface: 410

[0044] Bottom: 420

[0045] Transmission gear: 430

[0046] Inner wall protrusion: 440

[0047] Pen feed component: 500

[0048] Pressure plate: 510

[0049] Top surface constraint: 511

[0050] Worm gear first mounting hole: 512

[0051] First fixing slot of the rotating unit: 513

[0052] Base: 520; 520a; 520b

[0053] Bottom surface constraint: 521

[0054] Worm gear second mounting hole: 522

[0055] Second fixing slot of the rotating unit: 523

[0056] Rotary unit: 550; 550a

[0057] Rotor: 551

[0058] Worm gear: 552

[0059] Shaft: 553

[0060] Worm gear: 560

[0061] Straight teeth: 561

[0062] Spiral teeth: 562

[0063] Column: 563

[0064] Control unit: 600

[0065] Power supply: 700

[0066] Cover plate: 800

[0067] Assembly space: S Detailed Implementation

[0068] The detailed features and advantages of this utility model are described below in specific embodiments. The content is sufficient to enable any person skilled in the art to understand the technical content of this utility model and implement it accordingly. Based on the specification, claims and drawings disclosed in this specification, those skilled in the art can easily understand the related objectives and advantages of this utility model.

[0069] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0070] In the description of this embodiment, it should be noted that the terms "upper," "lower," etc., indicating orientation or positional relationship are defined with reference to the coordinates of the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In this utility model, the pen inlet end of the pencil sharpener in its upright state during normal use is considered upper.

[0071] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0072] Standard design:

[0073] Figure 13 This is a common structural diagram showing the combination of a rotary wheel unit and a central drive wheel. The top surface of the central drive wheel has protruding teeth that mesh with the worm gear in the rotary wheel unit for transmission. In this structure, the central drive wheel is restricted from upward movement because it is pressed down by the rotary wheel unit. This structure can easily cause the meshing between the worm gear in the rotary wheel unit and the protruding teeth on the top surface of the central drive wheel to be too tight or too loose, which can easily lead to gear damage or excessive noise, seriously affecting the lifespan or noise performance of the transmission mechanism.

[0074] Figure 14The patented design utilizes a central drive wheel similar to the one used in this invention. This transmission method, where the drive is transmitted from the sidewall to the worm gear and then further to the rotating wheel unit, is more stable and quieter. However, structurally, because the transmission is via the sidewall gear, the rotating wheel unit does not contact the top surface, while the central drive wheel bears a large torque. If not properly secured, this could lead to instability in the central drive wheel, resulting in a malfunction of the entire product. To limit the axial movement of the central drive wheel, a cover plate needs to be added to its upper end for fixation. This design not only complicates the structure and increases assembly difficulty but also significantly increases material and assembly costs, and increases the size of the electric pencil sharpener, failing to meet its portability requirements.

[0075] This patent solution:

[0076] Figure 1 This is a schematic diagram of the exploded view of the pen feeding assembly. The pen feeding assembly includes, from top to bottom along the axial direction, a pressure plate, two sets of rotating wheel units, a worm gear, and a base, while the central drive wheel is located between the top surface and the base.

[0077] Figure 2 This is a three-dimensional schematic diagram of the front and back of the central drive wheel. The central drive wheel is shaped like a hollow disc, containing drive teeth on the top, bottom, and side walls. The hollow inner wall of the central drive component also includes inner wall protrusions that can mate with the tool holder assembly. When the electric pencil sharpener is running, the tool holder drive component and the inner wall protrusions work together to synchronously transmit the rotation of the tool holder assembly to the central drive wheel.

[0078] Figure 3 This is a three-dimensional schematic diagram of the front and back of the pressure plate; the pressure plate is provided with a top surface constraint member, a first fixing groove for the rotating wheel unit and a first mounting hole for the worm gear along the axial downward direction. Specifically, in this schematic diagram, the top surface constraint member is a slender strip structure.

[0079] Figure 4 This is a three-dimensional schematic diagram of the front and back of the base; the base is provided with a bottom surface constraint member, a second fixing groove for the rotating wheel unit and a second mounting hole for the worm gear along the axial upward direction. Specifically, in this schematic diagram, the bottom surface constraint member is an annular protruding rib structure.

[0080] When the electric pencil sharpener is assembled, the first and second mounting holes of the worm gear are aligned along the axis, and the upper and lower ends of the worm gear are inserted into the first and second mounting holes for fixation. Similarly, the first and second fixing slots of the wheel unit are also aligned along the axis, allowing for the assembly of each wheel unit.

[0081] Figure 5 This is a side view of an electric pencil sharpener. Figure 6 yes Figure 5Schematic diagram of cross-section along the AA direction, see reference. Figures 5-6 It is known that the electric pencil sharpener also includes a control unit, a transmission component, a power supply, and a motor. The motor is electrically connected to the power supply, and the control unit can control the start and stop of the motor. The motor can drive the blade holder assembly through the drive unit.

[0082] Figure 7 , Figure 8 and Figure 9 This is a schematic diagram of the assembled pencil feed assembly, central drive wheel, and blade holder assembly. When the electric pencil sharpener is in operation, the blade holder assembly, under the control of the control unit, begins to rotate. This rotation is transmitted to the central drive wheel, causing it to rotate synchronously. The transmission teeth on the circumference of the central drive wheel mesh with spur teeth, further transmitting rotation to the worm gear, which also begins to rotate synchronously. The helical teeth on the side wall of the worm gear mesh with the various worm wheels on the rotating wheel unit, driving the rotating wheel unit's shaft to rotate. Simultaneously, the rotating wheel also begins to rotate. Since the pencil is directly gripped by two rotating wheels when it enters the electric pencil sharpener, automatic pencil feeding and retraction are achieved. The coordination between these components completes the rotational motion from the blade holder assembly to the central drive wheel and then to the rotating wheel unit.

[0083] like Figure 10 The diagram shows a top view of the assembled pen feed assembly, central drive wheel, and tool holder assembly. The top constraint component passes through the rotating wheel unit and abuts against the top transition space S. As can be seen from the diagram, the projection of the top constraint component onto the top surface of the central drive wheel does not interfere with the projection of the rotating wheel unit onto the top surface of the central drive wheel. This means that the projections of the top constraint component and the rotating wheel unit do not overlap or intersect. In other words, the top constraint component and other components, such as the central drive wheel, are interlocked.

[0084] Figure 11 This is a schematic diagram of the front view of the pen feed assembly - center drive wheel; Figure 12 yes Figure 11 A cross-sectional view along the CC direction shows the bottom surface of the central drive wheel abutting against the bottom constraint member on the base. Through the bidirectional abutment of the top and bottom constraint members, the central drive wheel is restricted from axial displacement. This method not only ensures reliable upper and lower limit positioning of the central drive wheel but also saves on a similar component. Figure 13 The central wheel pressure plate component is shown. This simplifies the structure and saves on materials and assembly costs, making the overall structure of the electric pencil sharpener more compact.

[0085] Specifically, the pen feed assembly includes a set of symmetrical and parallel rotating wheel units.

[0086] Meanwhile, the top constraint and pressure plate, and the bottom constraint and base are an integrated structure.

[0087] Industrial application

[0088] This utility model provides an electric pencil sharpener. Through the design of the cover plate structure of the pencil insertion mechanism, the central transmission wheel can be cleverly constrained, limiting its displacement along the axial direction and ensuring reliable fixation. This saves on product processing, material, and assembly costs. Furthermore, the overall structure is more compact, stable, and reliable, reducing the number of product parts and effectively improving the fault tolerance rate of product assembly and use.

[0089] The terminology and expressions used herein are for descriptive purposes only, and this invention should not be limited to these terms and expressions. The use of these terms and expressions does not mean the exclusion of any illustrative and descriptive equivalent features (or parts thereof), and it should be recognized that various modifications that may exist should also be included within the scope of the claims. Other modifications, variations, and substitutions may also exist. Accordingly, the claims should be considered to cover all such equivalents.

[0090] Similarly, it should be noted that although the present invention has been described with reference to the specific embodiments described above, those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and various equivalent changes or substitutions can be made without departing from the spirit of the present invention. Therefore, any changes or modifications to the above embodiments within the scope of the essential spirit of the present invention will fall within the scope of the claims of the present invention.

Claims

1. An electric pencil sharpener characterized by comprising: The electric pencil sharpener comprises a pencil feeding assembly, a central transmission wheel, a cutter holder assembly, a motor and a power supply, wherein: The motor is electrically connected with the power supply, and the motor can provide power to the cutter holder assembly, The cutter holder assembly can rotate under the drive of the motor, and in turn transmit the rotating power to the central transmission wheel, The central transmission wheel can rotate synchronously with the cutter holder assembly and drive the rotating unit of the pencil feeding assembly to rotate, The pencil feeding assembly further comprises a pressing plate and a base, the central transmission wheel is at least partially accommodated in a cavity formed between the pressing plate and the base, the pressing plate is provided with a top surface restraint, the base is provided with a bottom surface restraint, the top surface restraint abuts against the top surface of the central transmission wheel, and the bottom surface restraint abuts against the bottom surface of the central transmission wheel, so that the central transmission wheel only rotates around the axis direction and does not move up and down along the axis direction when the electric pencil sharpener performs the pencil sharpening action.

2. The electric pencil sharpener according to claim 1, wherein The pencil feeding assembly comprises two groups of rotating units and a worm, the two groups of rotating units are arranged in parallel and are axisymmetric, wherein the rotating unit comprises a rotating wheel, a worm wheel and a rotating shaft, the rotating unit is arranged above the central transmission wheel in the axial direction, the worm can transmit the rotation of the central transmission wheel to the rotating unit, the top surface restraint is an elongated column structure, and the axial projection of the top surface restraint at the abutting position is independent of the axial projection of the rotating unit on the top surface.

3. The electric pencil sharpener according to claim 2, wherein The bottom surface restraint is a protruding rib structure extending upward from the base in the axial direction.

4. The electric pencil sharpener according to claim 3, wherein The rotating unit comprises a rotating wheel, the rotating wheel clamps the pencil when cutting the pencil, and the rotating wheel is made of soft rubber.

5. The electric pencil sharpener according to claim 4, wherein The worm comprises straight teeth and helical teeth, the side wall of the central transmission wheel comprises transmission teeth, the rotating wheel is coaxially arranged with the worm wheel, the straight teeth can mesh with the transmission teeth, and the helical teeth can mesh with the worm wheel.

6. The electric pencil sharpener according to claim 5, wherein The top surface restraint is integrally arranged with the pressing plate.

7. The electric pencil sharpener according to claim 6, wherein The bottom surface restraint is integrally arranged with the base.

8. The electric pencil sharpener according to claim 7, wherein The electric pencil sharpener further comprises a control unit for controlling the start and stop of the motor.

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