Arc-shaped hand warmer and charging box

Abstract

The utility model provides a kind of arc hand warmer and charging box, including heating assembly, crescent shell, first arc part, second arc part and end face arc part;The utility model has adopted crescent shell, relative to traditional circle and rectangle, can avoid the problem that rectangular structure is easily compressed palm due to corner, and the area of circle structure and palm is small, and long time holding easily leads to hand fatigue;And the cross-sectional width size of crescent shell gradually decreases from middle to both ends, when hand holds, the end inside of crescent shell can be lapped in human palm volar interosseous, to facilitate avoiding the drop of hand warmer, and then reduce the holding force of palm, the process is designed for palm physiological curve, so it can comfortably adapt to most adult palm profile, improve the use experience of user.

Description

Technical Field

[0001] This utility model relates to the field of hand warmer technology, specifically to an arc-shaped hand warmer and its charging box. Background Technology

[0002] As a commonly used portable warming device in winter, the core requirements for hand warmers are concentrated on heating uniformity, grip comfort, and functional expandability. Existing hand warmers mostly adopt rectangular and circular shapes, such as those disclosed in patent documents with authorization announcement numbers "CN218269253U" and "CN215229126U". These types of hand warmers have poor grip adaptability; for example, the corners of rectangular structures can easily compress the palm, while circular structures have a small contact area with the palm, which can easily lead to hand fatigue after prolonged use, thus affecting the user experience. Utility Model Content

[0003] The purpose of this utility model is to design an arc-shaped hand warmer and charging box to solve the problems mentioned in the background art. To achieve the above objective, this utility model provides the following technical solution: an arc-shaped hand warmer and charging box, including a crescent-shaped outer shell with a heating component inside. The crescent-shaped outer shell includes a first arc portion and a second arc portion. The two ends of the first arc portion and the second arc portion are smoothly transitioned through end face arc portions. The symmetry planes of the first arc portion and the second arc portion coincide, and the bending direction of the first arc portion is consistent with the bending direction of the second arc portion. The center of the first arc portion does not coincide with the center of the second arc portion, and the radius of the first arc portion is smaller than the radius of the second arc portion. The cross-sectional width of the crescent-shaped outer shell gradually decreases from the middle to both ends.

[0004] Furthermore, the radius R1 of the first arc portion is 40mm-60mm, the radius R2 of the second arc portion is 70mm-90mm; and the chord length L and the distance between the centers d, The chord length is defined as the farthest distance between the inner sides of the two end face arc portions, and the center distance is defined as the distance between the center of the first arc portion and the center of the second arc portion, wherein the chord length L is 110mm-130mm; and the center distance d is 20mm-30mm.

[0005] Furthermore, it also includes a transition angle A, which is defined as the acute angle between the tangent line that is simultaneously tangent to the second arc portion and the end face arc portion and the line of symmetry in the plane of symmetry of the second arc portion; the value of the transition angle A is 69.5°-73.5°.

[0006] Furthermore, the cross-sectional width of the crescent-shaped outer shell decreases at a rate of 0.1-0.15 mm / mm from the middle to both ends.

[0007] Furthermore, the heating assembly includes a heating element attached to the inner wall of the crescent-shaped outer shell and a power module disposed inside the crescent-shaped outer shell. The heating element is coated with a graphene coating, and the heating element is provided with two electrode plates that are connected to the power module and used to supply power to the graphene coating.

[0008] Further, the thickness of the graphene coating is 0.03-0.04 mm, and the thickness of the electrode sheet is 0.1-0.15 mm; or, the thickness of the graphene coating is 0.04-0.05 mm, and the thickness of the electrode sheet is 0.15-0.2 mm.

[0009] Furthermore, the thickness of the graphene coating near the first arc portion is 0.04-0.05 mm, and the thickness of the graphene coating near the second arc portion is 0.03-0.04 mm.

[0010] Furthermore, the length of the heating element is 45mm-65mm, and the width of the heating element is 15mm-20mm.

[0011] Furthermore, a charging contact is provided on the second arc portion near the arc portion of the end face.

[0012] Furthermore, power indicator lights are provided on both the upper and lower surfaces of the arc portion of the end face.

[0013] Furthermore, a start switch is provided on the first arc portion.

[0014] This utility model also discloses a charging box, including a box body, in which two charging slots adapted to the above-mentioned arc-shaped hand warmer are provided. The two charging slots are symmetrically arranged and the second arc portion is located inside the charging slot. A charging terminal is provided at the joint between the charging slot and the second arc portion. One arc-shaped hand warmer can be adapted to any one of the charging slots.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model adopts a crescent-shaped shell, which, compared with the traditional round and rectangular shells, avoids the problem of rectangular structures causing pressure on the palm due to the corners, and the problem of round structures having a small contact area with the palm, which can easily lead to hand fatigue after holding for a long time. In addition, the cross-sectional width of the crescent-shaped shell gradually decreases from the middle to both ends. When a person holds it, the inner side of the end of the crescent-shaped shell can overlap the web of the palm, which helps to prevent the hand warmer from falling off and reduces the grip pressure. This process is designed according to the physiological curve of the palm to improve the user experience. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is an exploded view of the present invention and the charging box. Figure 2 A structural schematic diagram of the crescent-shaped shell from two perspectives; Figure 3 This is a schematic diagram showing the dimensions of various parameters of this utility model.

[0018] The components include: 1. Charging slot; 2. Crescent-shaped outer shell; 3. First arc portion; 4. Second arc portion; 5. End face arc portion; 6. Power indicator light; 7. Power switch; 8. Charging contacts. Detailed Implementation

[0019] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.

[0020] Example: Please refer to Figures 1-3 A curved hand warmer includes a crescent-shaped outer shell 2 with an internal heating element. The crescent-shaped outer shell 2 includes a first arc portion 3 and a second arc portion 4. The two ends of the first arc portion 3 and the second arc portion 4 are smoothly transitioned by end face arc portions 5. The planes of symmetry of the first arc portion 3 and the second arc portion 4 coincide, and the bending direction of the first arc portion 3 is consistent with the bending direction of the second arc portion 4. Therefore, the crescent-shaped outer shell 2 is used. Compared with traditional circular and rectangular structures, it avoids the problem of rectangular structures causing pressure on the palm due to the corners, and the problem of circular structures having a small contact area with the palm for extended periods. The problem of hand fatigue caused by gripping is addressed by the fact that the center of the first arc portion 3 does not coincide with the center of the second arc portion 4, and the radius of the first arc portion 3 is smaller than that of the second arc portion 4. The width of the crescent-shaped outer shell 2 gradually decreases from the middle to both ends. Thus, when a person holds it, the inner side of the end of the crescent-shaped outer shell 2 overlaps with the web of the hand, which helps to prevent the hand warmer from falling off and reduces the gripping force. This process is designed according to the physiological curve of the hand, so it can comfortably fit the palm contour of most adults and improve the user experience.

[0021] The first arc portion 3 of this invention has a radius R1 of 40mm-60mm, and the second arc portion 4 has a radius R2 of 70mm-90mm; it also includes a chord length L and a center distance d. The chord length is defined as the farthest distance between the inner sides of the two end arc portions 5, and the center distance is defined as the distance between the center of the first arc portion 3 and the center of the second arc portion 4. Specifically, the chord length L is 110mm-130mm, and the center distance d is 20mm-30mm. In this embodiment, the preferred values ​​are R1=50mm, R2=80mm, L=120mm, and d=25mm. At the mm level, the palm heel suspension rate and palm fit are both greater than the original rectangular and circular shapes, thus allowing for a tighter fit to the palm heel, eliminating gaps and resolving the instability caused by palm heel suspension in existing products. It also improves adaptability to hand width and grip depth, achieving a gapless palm fit. Furthermore, finger pressure is reduced compared to traditional rectangular and circular shapes, dispersing finger pressure and avoiding the pressure caused by excessively steep corners and curves in existing products. This meets the market demand for a design goal of "no soreness or swelling after 2 hours of continuous gripping." The testing process for palm heel suspension rate, palm fit, and finger pressure is as follows. (1) Select Comparison 1 (square): side length 90mm, thickness 25mm (mainstream model sold in the market); Comparison 2 (round): diameter 100mm, thickness 22mm (mainstream round model sold in the market, without palm fit design, the outer shell is a standard round shape).

[0022] (2) Selection of experimental subjects: Based on the different hand shapes of adults, 100 healthy adults (aged 20-40 years) were selected and grouped according to hand size: Group A (small hands): Hand length 180-190mm, width 70-73.5mm (30 people); Group B (Medium Hand Size): Hand length 191-205mm, width 76-85mm (40 people); Group C (Large Hands): Hand length 206-220mm, width 86-90mm (30 people); All objects were free of hand diseases and had the same gripping habits (naturally curved grip, palm against the concave surface of the outer shell). (3) Experimental equipment: For palm heel suspension rate: a 3D structured light scanner (accuracy 0.01mm) was used to capture the gap area between the palm heel and the shell; For palm fit: a flexible pressure sensor array (resolution 0.1kPa, sampling rate 100Hz) was used to attach to the concave surface of the shell and record the contact area; For finger pressure force: a miniature tension / pressure force gauge (accuracy 0.01N) was used to fix the contact positions of the index finger, middle finger and ring finger respectively. (4) Experimental steps: 1. Palm heel suspension rate test (each sample group was tested 3 times, and the average value was taken) The subjects sat naturally with their arms hanging down in a relaxed state, holding the sample (the experimental group's palms were placed against the concave surface, Control 1's palms against the flat surface, and Control 2's palms against the curved surface, with fingers naturally wrapped around both sides of the outer shell). A 3D scanner was used to scan the contact area between the palm and the sample, focusing on capturing the gap between the palm heel (the connection between the palm and wrist) and the outer shell. The "suspended area" (the area where the palm heel does not contact the outer shell) was calculated using scanning software, and the palm heel suspension rate was calculated according to the formula: Palm heel suspension rate = (Palm heel suspended area / Total palm heel contact area) × 100%. The suspension rates of the experimental group, Control 1, and Control 2 were tested separately, and the data for each group were recorded. 2. Palm fit test The flexible pressure sensor array was completely attached to the contact side of the sample shell (experimental group covered the concave surface, control 1 covered the flat surface, and control 2 covered the semi-circular surface). The sensor was calibrated (the reading was 0 at zero pressure). The test subject held the sample in a standard posture for 5 seconds (avoiding excessive or insufficient force). The sensor recorded the "effective contact area" (the area with pressure ≥1 kPa is considered effective contact). The "palm contact area area" (the area from the base of the fingers to the base of the palm) of the test subject was measured with a palm measuring instrument. The palm fit was calculated according to the formula: Palm fit = (effective contact area / palm contact area area) × 100%. The test was repeated 3 times, and the average value was taken to compare the fit differences of the three groups of samples.

[0023] 3. Finger pressure test Three miniature pressure gauges were fixed to the contact positions of the sample shell corresponding to the middle sections of the index, middle, and ring fingers (marked as F1, F2, and F3). The test subject held the sample in a standard posture for 5 seconds, and the real-time pressure values ​​of the three pressure gauges were recorded. The readings after stabilization were taken. The "average finger pressure force" was calculated as (F1 + F2 + F3) / 3, and the "maximum pressure force" (the maximum value among the three positions) was recorded. Each group of samples was tested 5 times (with a 1-minute interval to avoid hand fatigue), and the average value was taken. The pressure data of the three groups of samples were compared.

[0024] (5) Experimental data 1. Palm heel suspension rate data (unit: %) It is evident that the palm heel suspension rate of the samples of this utility model is ≤6.5%, which is lower than that of the control group (square 19.8%-32.1%, round 26.1%-29.5%). The round control group, due to its perfectly circular outer shell (100mm in diameter), cannot conform to the natural curvature of the palm heel, resulting in a large gap between the palm heel and the outer shell. In contrast, the second arc portion 4 (R2=80mm) of this utility model can precisely match the curvature of the palm heel, effectively eliminating the suspension gap and solving the problem of unstable grip caused by the palm heel suspension in existing products.

[0025] 2. Palm fit data (unit: %) It can be seen that the palm fit of this utility model is ≥90.7%, with the middle palm group (Group B) reaching 95.1%, which is 30%-35% higher than the square sample and 22%-27% higher than the circular sample. Although the circular control group has an arc structure, the curvature of the perfect circle (radius 50mm) does not match the natural curvature of the palm well, and the diameter of 100mm does not match the width of the palm, resulting in gaps on both sides of the palm. In contrast, the second arc part 4 (R2=80mm) and L=120mm of this utility model are highly compatible with the width and curvature of the palm, achieving a gapless fit.

[0026] 3. Finger pressure data (unit: N) It is evident that the average finger pressure of this invention is only 1.8N, with a maximum pressure of 2.5N, representing a 57% reduction compared to the square sample and a 55% (average pressure) and 52% (maximum pressure) reduction compared to the circular sample. While the circular control group lacks sharp edges, the perfectly circular shell requires excessive bending and wrapping of the fingers, leading to concentrated force on the finger joints. In contrast, the smooth transition between the end arc portion 5 and the second arc portion 4 of this invention, with the second arc portion 4 (R2=80mm), avoids sharp edges and accommodates the natural wrapping shape of the fingers, distributing pressure and meeting the design goal of "no soreness or swelling after 2 hours of continuous gripping."

[0027] In this embodiment, a transition angle A is also included. The transition angle A is defined as the acute angle between the tangent line that is simultaneously tangent to the second arc portion 4 and the end face arc portion 5 and the line of symmetry in the plane of symmetry of the second arc portion 4. The value of the transition angle A is 69.5°-73.5°. Experiments have shown that when the value of the transition angle A is greater than 73.5°, the end face arc portion 5 provides little support to the tiger's mouth, thereby increasing the user's grip strength on the hand warmer. When the value is less than 69.5°, it is easy to cause a decrease in palm fit and an excessively steep arc, resulting in a feeling of pressure during the transition. Therefore, in this embodiment, the preferred value of the transition angle A is 71°, which can fully ensure palm fit, appropriate squeezing force, and small grip strength, thereby improving the user's experience.

[0028] In this embodiment, the cross-sectional width of the crescent-shaped outer shell 2 decreases at a rate of 0.1-0.15 mm / mm from the middle to both ends, thus ensuring that the hand warmer has a uniformly small rate from the middle to both ends, which matches the changes in length from the middle finger to the little finger and from the middle finger to the index finger, thereby better adapting to the physiological curve of the palm and conforming to the contour of the human hand, thereby improving the user experience.

[0029] The heating assembly includes a heating element adhered to the inner wall of a crescent-shaped outer shell and a power module located inside the crescent-shaped outer shell. The heating element is coated with a graphene coating, and it has two electrode plates connected to the power module for supplying power to the graphene coating. Specifically, in this embodiment, experimental results show that, with preferred R1=50mm, R2=80mm, L=120mm, and d=25mm, a heating element length of 60mm and a width of 18.5mm provides the most ideal heat generation, energy consumption, and usage time. Furthermore, the graphene coating exhibits a gradually changing thickness, with 0.05mm near the first arc portion 3 and 0.03mm near the second arc portion 4. The electrode plates use a thickness of 0.1mm. A 5mm thick copper foil is adhered to the heating element using high-temperature conductive adhesive. This gradient thickness effectively compensates for the difference in heat radiation path caused by R2 being greater than R1. By adjusting the thickness gradient, heat conduction efficiency is improved, ensuring uniform heat distribution across the curved surface and preventing localized overheating or uneven heat dissipation. This significantly enhances the heat radiation uniformity and user comfort of the hand warmer. The coating material is graphene, and its working principle is as follows: the power module supplies power to the graphene coating, generating heat through the Joule effect and transferring it to the outer shell to heat the user's hand. Compared to the previous heating method combining heating wires and aluminum plates, this method produces more uniform and gentler heat. Furthermore, the heating component includes a temperature sensor to control the temperature of the heating element.

[0030] Furthermore, this utility model also discloses a charging case for charging the aforementioned hand warmer. To ensure continuous use of the hand warmer, or to ensure both of the user's hands are warmed, typically one charging case is paired with two hand warmers. When the hand warmer runs out of power, it is placed in the charging case for recharging. Because the hand warmer with its crescent-shaped outer shell 2 has an irregular structure, the charging case disclosed in this utility model includes a box body, and inside the box are two charging slots 1 adapted to the aforementioned arc-shaped hand warmer. The two charging slots 1 are symmetrically arranged, and the second arc portion 4 is positioned... Inside the charging slot 1, a charging terminal matching the charging contact 8 is provided at the mating point between the charging slot 1 and the second arc portion 4 for charging the hand warmer. It is worth mentioning that in the charging box of this utility model, any arc-shaped hand warmer can be adapted to any charging slot 1; thus, the crescent-shaped hand warmer can be charged regardless of which side faces the charging slot 1. In addition, power indicator lights 6 are provided on the upper and lower surfaces of the arc portion 5 to facilitate observation of whether the power consumption has been completed and whether the charging is complete. The first arc portion 3 is provided with a start switch 7 for starting and stopping the hand warmer.

[0031] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "upper," "lower," "left," "right," "front," "back," and similar expressions used in this document are for illustrative purposes only.

[0032] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. An arc-shaped hand warmer, characterized in that, The device includes a crescent-shaped outer shell with an internal heating component. The crescent-shaped outer shell includes a first arc portion and a second arc portion. The two ends of the first arc portion and the second arc portion are smoothly transitioned by end face arc portions. The symmetry planes of the first arc portion and the second arc portion coincide, and the bending direction of the first arc portion is consistent with the bending direction of the second arc portion. The center of the first arc portion does not coincide with the center of the second arc portion, and the radius of the first arc portion is smaller than the radius of the second arc portion. The cross-sectional width of the crescent-shaped outer shell gradually decreases from the middle to both ends.

2. The arc-shaped hand warmer according to claim 1, characterized in that, The radius R1 of the first arc portion is 40mm-60mm, and the radius R2 of the second arc portion is 70mm-90mm; as well as the chord length L and the distance between the centers d. The chord length is defined as the farthest distance between the inner sides of the two end face arc portions, and the center distance is defined as the distance between the center of the first arc portion and the center of the second arc portion, wherein the chord length L is 110mm-130mm; and the center distance d is 20mm-30mm.

3. The arc-shaped hand warmer according to claim 2, characterized in that, It also includes a transition angle A, which is defined as the acute angle between the tangent line that is simultaneously tangent to the second arc portion and the end face arc portion and the line of symmetry in the plane of symmetry of the second arc portion; the value of the transition angle A is 69.5°-73.5°.

4. The arc-shaped hand warmer according to claim 2, characterized in that, The cross-sectional width of the crescent-shaped shell decreases at a rate of 0.1-0.15 mm / mm from the middle to both ends.

5. The arc-shaped hand warmer according to claim 2, characterized in that, The heating assembly includes a heating element attached to the inner wall of the crescent-shaped outer shell and a power module disposed inside the crescent-shaped outer shell. The heating element is coated with a graphene coating and has two electrode plates that are connected to the power module and used to supply power to the graphene coating.

6. The arc-shaped hand warmer according to claim 5, characterized in that, The thickness of the graphene coating is 0.03-0.04 mm, and the thickness of the electrode sheet is 0.1-0.15 mm. Alternatively, the thickness of the graphene coating is 0.04-0.05 mm, and the thickness of the electrode sheet is 0.15-0.2 mm.

7. The arc-shaped hand warmer according to claim 6, characterized in that, The thickness of the graphene coating near the first arc portion is 0.04-0.05 mm, and the thickness of the graphene coating near the second arc portion is 0.03-0.04 mm.

8. The arc-shaped hand warmer according to claim 5, characterized in that, The length of the heating element is 45mm-65mm, and the width of the heating element is 15mm-20mm.

9. The arc-shaped hand warmer according to any one of claims 1-8, characterized in that, A charging contact is provided on the second arc portion near the arc portion of the end face.

10. A charging case, comprising a case body, characterized in that, The box is provided with two charging slots adapted to the arc-shaped hand warmer of claim 9. The two charging slots are arranged symmetrically and the second arc portion is located inside the charging slot. One arc-shaped hand warmer can be adapted to either of the charging slots.

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