Large-magnetic-force tool head extension rod with magnet end face suction force adjusting structure
By introducing a magnet end face suction force adjustment structure into the power tool head extension rod, including magnetic force adjustment and rear magnetic conductive structure, the problem of insufficient or excessive magnetic suction force of the power tool at high speed is solved, and convenient bit replacement and nail support effect are achieved.
Patent Information
- Application Number
- CN202410254144.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-06
- Publication Date
- 2025-09-09
AI Technical Summary
The magnetic attraction force of the connecting rod of existing power tools is insufficient, and it cannot effectively straighten the screws at high speeds and is difficult to replace. When the magnetic attraction force is too strong, the tool head is difficult to pull out, affecting the convenience of operation.
A large magnetic tool head extension rod with a magnet end face suction force adjustment structure is designed, including a magnet, a rod sleeve, a magnetic adjustment structure and a rear magnetic conductive structure. The magnetic suction force is adjusted through a thin sheet or a ring to ensure the magnetic adaptability adjustment between the bit and the magnet.
It achieves the easy replacement of the bit while ensuring the supporting nail effect, and improves the convenience of operation and the adaptability of the magnetic suction force.
Smart Images
Figure CN120606357A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a large magnetic tool head extension rod with a magnet end surface suction force adjustment structure, belonging to the technical field of power tool accessories. Background Art
[0002] Heavy power tools are becoming increasingly powerful and their speeds are increasing. Operators require extension rods with greater magnetic attraction to hold the tool bit and straighten the screws. Existing extension rods on the market have limited internal magnetic force, which only meets the needs of holding small screws. However, they cannot guarantee the straightening of screws at high speeds or prevent them from being thrown out at high speeds. Furthermore, they cannot meet the needs of one-handed operation. Furthermore, as power tools become more powerful, the tool bit and the screw are prone to deformation and jamming during nailing. These problems can be solved by increasing the magnetic attraction of the extension rod.
[0003] The aforementioned magnetic attraction consists of two types: one for the bit itself, and the other for the tool head's attraction to the screw it holds. The new high-magnetic tool head adapter, by increasing the diameter and volume of the built-in magnets and leveraging the front and rear magnetic adjustment structures, covers a larger magnetic pole surface, allowing more magnetic lines of force to form a closed loop around the tool head. This not only increases the attraction to the tool head itself, but also increases the attraction to the screw through the tool head itself.
[0004] This brings up a new problem. Because the magnetic attraction is too strong, although the suction force of the tool head tip on the screw achieves the purpose of supporting the screw and is suitable for the use requirements of heavy-duty and high-speed equipment, it makes the tool head, especially some small-sized tool heads, difficult to pull out. Sometimes pliers must be used to replace them, which is very troublesome. However, if the overall attraction of the magnet is lowered, the bit can be pulled out more easily, but the magnetic force of the bit tip is not enough to straighten the screw.
[0005] From the above description, it can be seen that the ideal state of the technology is to ensure that the screwdriver bit has a relatively ideal nail-supporting effect, so that the screwdriver bit can adjust the adsorption force between the screwdriver bit and the end face of the internal magnet as needed to ensure that the screwdriver bit can be easily and conveniently replaced. Summary of the Invention
[0006] In order to solve the deficiencies of the prior art, the object of the present invention is to provide a large magnetic tool head extension rod with a magnet end surface suction force adjustment structure.
[0007] In order to achieve the above objectives, the present invention adopts the following technical solutions: A large magnetic tool head extension rod with a magnet end face suction adjustment structure includes a magnet, a rod sleeve, a magnetic adjustment structure, and a rear magnetic conductive structure. The magnetic adjustment structure, the magnet, and the rear magnetic conductive structure are sequentially arranged inside the rod sleeve, and the rear magnetic conductive structure is adsorbed on the end of the magnet. The magnetic force adjustment structure is located between the magnet and the connected bit; The magnetic adjustment structure is a structure including a thin sheet, a circular ring, or a combination of a thin sheet and a circular ring.
[0008] As a preferred solution, the rod sleeve is made of non-magnetic material.
[0009] As a preferred solution, the connecting rod sleeve includes a bit connecting hole, an intermediate accommodating hole, and a connecting rod handle connecting hole arranged in sequence. The cross-section of the intermediate accommodating hole is circular, and the diameter of the intermediate accommodating hole is not less than the maximum diameter of the bit connecting hole and not less than the minimum diameter of the connecting rod handle connecting hole.
[0010] As a preferred solution, the cross-sections of the bit connecting hole and the connecting hole of the connecting rod handle are both regular polygons.
[0011] As a preferred solution, when the magnetic force adjustment structure is a thin sheet, the thin sheet is one of a non-magnetic sheet, an iron sheet or a nickel sheet.
[0012] As a preferred solution, when the magnetic force regulating structure is a circular ring, the circular ring is one of a right-angled circular ring, a circular ring with an inner bevel, or a circular ring with a circular cross section, and the inner bevel contacts the chamfer of the tail of the connected screwdriver.
[0013] As a preferred solution, when the magnetic force adjustment structure is a structure combining a thin sheet and a circular ring, the thin sheet and the circular ring are an integrated structure with equal outer diameters or a concentric stacked structure of thin sheets and circular rings with equal outer diameters, and the thin sheet is placed between the magnet and the circular ring.
[0014] As a preferred solution, the connecting rod handle includes a small-head handle section and a large-head handle section inserted into the connecting rod handle connecting hole, and the minimum diameter of the large-head handle section is not less than the diameter of the connected magnet.
[0015] As a preferred solution, the circular ring with a circular cross section is an open ring or a closed ring structure.
[0016] As a preferred solution, the rear magnetic conductive structure includes a large head handle section, and the large head handle section is made of magnetic conductive material.
[0017] The beneficial effects achieved by the present invention are: Compared to existing technologies, this invention utilizes a magnetic force adjustment structure between the magnet and the bit to adjust the magnetic field between them, making it easier to replace the bit. The magnetic force adjustment mechanism and the rear magnetic conductive structure are located at both ends of the magnet, directing the magnet's magnetic flux lines as close to the tip of the bit as possible, thus enhancing the screw-holding effect.
[0018] The present invention can ensure that the screwdriver bit has a relatively ideal nail supporting effect, and the adsorption force between the screwdriver bit and the end face of the internal magnet can be adjusted as needed, so as to ensure that the screwdriver bit can be easily and conveniently replaced. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 is a partial cutaway view of embodiment 1 of the present invention; Figure 2 is a cross-sectional view of the connecting rod sleeve of the present invention; Figure 3 is a cross-sectional view of the extension rod sleeve of the present invention; Figure 4 This is a cross-sectional view of the thin sheet and the ring in the second embodiment of the present invention, which adopt a separated structure; Figure 5 This is a cross-sectional view of the integrated structure of the sheet and the ring in the second embodiment of the present invention; Figure 6 This is a force comparison diagram of a screwdriver bit in the third embodiment of the present invention and in the prior art that does not use a magnetic force adjustment structure; Figure 7 is a cross-sectional view of a circular ring with an inner bevel in the third embodiment of the present invention; Figure 8 This is a schematic diagram of the distribution of magnetic flux lines when using different magnets and post-magnetic conductive structures; The meanings of the reference numerals in the figure are: 1- small head handle section; 2- large head handle section; 3- magnet; 4- connecting rod sleeve; 5- magnetic adjustment structure; 6- bit; 41- bit connecting hole; 42- middle accommodating hole; 43- connecting rod handle connecting hole; 5a- thin sheet; 5b- circular ring with inner bevel; 5c- right-angle circular ring; 5d- circular ring with circular cross section. DETAILED DESCRIPTION
[0020] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.
[0021] like Figure 1As shown: The present invention discloses a large magnetic tool head extension rod with a magnet end face suction adjustment structure, including a magnet 3, a connecting rod sleeve 4, a magnetic adjustment structure 5 and a rear magnetic conductive structure. The magnetic adjustment structure 5, the magnet 3 and the rear magnetic conductive structure are arranged in sequence inside the connecting rod sleeve 4, and the rear magnetic conductive structure is adsorbed on the end of the magnet 3. In the present invention, the "rear" in the "rear magnetic conductive structure" refers to the end closer to the power input device, which is only for the convenience of expressing the orientation and does not limit the protection scope of the present invention. Among them, the magnetic adjustment structure 5 is located between the magnet 3 and the connected bit. The magnetic adjustment structure 5 in the present invention is one of a thin sheet 5a, a ring, and a structure combining a thin sheet 5a and a ring. The connecting rod sleeve 4 in the present invention is preferably made of a non-magnetic material, such as metals such as aluminum, copper, stainless steel, and also includes non-metallic materials such as plastic, ceramics, and wood, among which stainless steel and aluminum are the most commonly used.
[0022] like Figure 2 and Figure 3 As shown, the connecting rod sleeve 4 includes a bit connection hole 41, an intermediate receiving hole 42, and a connecting rod handle connection hole 43, which are arranged in sequence. The intermediate receiving hole 42 has a circular cross-section and is used to accommodate the magnet 3 and the magnetic force adjustment structure 5. The diameter (D2) of the intermediate receiving hole 42 is not less than the maximum diameter (D1a) of the bit connection hole 41 and not less than the minimum diameter (D3) of the connecting rod handle connection hole 43. The cross-sections of the bit connection hole 41 and the connecting rod handle connection hole 43 are both regular polygons, commonly regular hexagons. Their maximum diameter is the length of their longest diagonal (D3a, D1a), and their minimum diameter is the distance between a pair of opposite sides (D3, D1).
[0023] The connecting rod shank includes a small end shank segment 1 and a large end shank segment 2 that is inserted into the connecting rod shank connection hole 43. The minimum diameter of the large end shank segment 2 is larger than the diameter of the connected magnet 3. The minimum diameter of the connecting rod shank can be referred to the minimum diameter (D3) of the connecting rod shank connection hole 43.
[0024] Embodiment 1: When the magnetic force adjustment structure 5 is a thin sheet 5a, the thin sheet 5a is a non-magnetic sheet or an iron sheet. When a non-magnetic sheet is used, it mainly serves to increase the distance between the tail of the screwdriver bit 6 and the magnet 3. In this state, the magnetic attraction of the magnet 3 on the screwdriver bit 6 decreases rapidly with the increase of the thickness of the thin sheet 5a, but the supporting effect of the screwdriver bit 6 only decreases slightly.
[0025] Of course, thin sheet 5a can also be made of a magnetically conductive iron sheet. When this is used, since it fully contacts the magnetic pole surface, which is larger than the end face of the tool head, it can guide more magnetic lines of force through the tool head, reducing magnetic flux leakage. Compared to a situation where the tool head directly contacts the magnet end face, this sheet objectively increases the magnet's attraction to the tool head, preventing the tool head from being easily pulled out by external forces. The diameter of thin sheet 5a is preferably equal to that of magnet 3. Thin sheet 5a also acts as a buffer against impacts from bit 6 and protects magnet 3.
[0026] Example 2: Figure 4 yes Figure 5 As shown: The magnetic force adjustment structure 5 in this embodiment is a structure in which a thin sheet 5a is combined with a circular ring, and the thin sheet 5a and the circular ring are an integrated structure with the same outer diameter ( Figure 5 ) or a concentric stacking structure of thin sheets 5a with equal outer diameter and a ring ( Figure 4 ), The sheet 5a is placed between the magnet 3 and the ring. Figure 4 The middle thin sheet 5a and the circular ring are designed as a split structure. When the magnetic adjustment structure 5 is a circular ring, the circular ring is one of a right-angled circular ring 5c, a circular ring with an inner bevel 5b or a circular ring 5d with a circular cross section, and the inner bevel is in contact with the chamfer of the tail of the connected screwdriver bit. When the circular ring 5d with a circular cross section is used, the circular ring can be an open ring or a closed ring. When an open ring is used, since it has a certain elastic force in the diameter direction, it has a certain buffering effect on the insertion of the screwdriver bit 6.
[0027] The advantage of adopting this embodiment is that the end plane of the tool head does not directly contact the magnetic adjustment mechanism, but the side surface and chamfered surface of the tool head contact the inner slope angle surface of the adjustment mechanism. When the tool head is pulled out, the direction of the force for pulling out the tool head forms a certain angle with the magnetic surface in the connecting rod that attracts the tool head ( Figure 4 and Figure 5 The angle is not 90 degrees, which can reduce the difficulty of pulling out the bit. In this case, the bit 9 can be separated from the connecting rod with less force.
[0028] In this embodiment, although the chamfered surface of the screwdriver bit 6 contacts the inner slope angle surface of the adjustment mechanism, reducing the force required to separate the screwdriver bit 6 and the magnet 3, from the perspective of the magnetic circuit, the magnetic path still maintains an unobstructed state in which the magnetic conductors are connected to each other. It is just that the magnetic line path is only bent at this location, and does not have a significant impact on the "quantity / density" of the magnetic lines of force transmitted between the two.
[0029] Example 3: Figure 6 and Figure 7As shown: the magnetic adjustment structure 5 in this embodiment has only a circular ring 5b, which can be a right-angled circular ring 5c or a circular ring 5b with an inner bevel. When the circular ring 5b with an inner bevel is used, its inner bevel matches the chamfer of the tail of the connected screwdriver.
[0030] like Figure 8 As shown, Figure 8 The elliptical arc curve in represents the distribution of magnetic flux lines. Figure 8 The volumes of the magnets 3 in the U figure and the V figure are equal, but the diameter of the magnet 3 in the U figure is relatively small, and the thickness of the magnet 3 in the V figure is relatively small. The end face of the magnet and the tool head in the V figure are provided with an iron magnetic conductive sheet (5a), whose area is equivalent to the end face of the magnetic pole. The rear end face of the magnet 3 in the V figure is provided with a larger area of the magnetic conductive body, the end face of the large head section of the connecting rod handle.
[0031] 1. In Figure U, because the outer diameter of the magnet is smaller than both the end of the tool head and the end of the rear shank, some magnetic flux lines will move directly from the chamfer at the tail of bit 6 to the rear end of magnet 3. We can call this "magnetic leakage." This "magnetic leakage" reduces the number of magnetic flux lines inside bit 6, thereby weakening the bit's ability to attract nails.
[0032] 2. In contrast, in Figure V, a magnet 3 with a relatively large outer diameter is used. At the same time, a leading magnetic plate with an area equivalent to the front magnetic pole surface and a rear magnetic plate with an area larger than the rear end surface of the magnet are used. This configuration structure can make the magnetic flux lines at both ends of the magnet 3 extend as much as possible along the axial direction of the screwdriver bit 6 and the large head handle section 2. In this way, the density of the magnetic flux lines distributed near the nail is greater, which can improve the nail supporting effect.
[0033] 3. Let’s compare the V chart and the W chart: Although the magnet diameter and thickness parameters used in the two diagrams are the same, since the magnet 3 in the V diagram adopts a rear magnetic conductive structure with a larger outer diameter and a front magnetic conductive sheet whose area fully fits the front end surface of the magnet, the V diagram can make more magnetic flux lines pass through the large head handle section 2 and the tool head to form a full closure, compared with the W diagram, thereby reducing the above-mentioned "magnetic leakage" phenomenon.
[0034] At the same time, due to the principle of magnetic field symmetry, the magnetic flux lines are symmetrically distributed before and after the magnet 3 (the symmetry line is Figure 8 As shown in the horizontal dotted line in the figure, the large head section 2 of the connecting rod handle with a larger outer diameter and a longer length can guide the magnetic flux lines to converge more toward the tip of the distal end of the tool head in the vertical direction as shown in the figure. Therefore, the magnetic flux lines are also closer to the nail in the bit 6, which improves the nail supporting force effect.
[0035] To summarize, Figure 8 Compared with the U diagram, the V diagram in the figure mainly increases the diameter and the area of the magnetic extreme surface, thereby improving the magnetic force and the supporting effect.
[0036] Figure 8 Compared with the W diagram, the V diagram in the figure improves the magnetic force and the supporting effect by changing the magnetic conductivity of the front and rear ends of the magnet.
[0037] Compared with the prior art, the present invention designs a magnetic force adjustment structure 5 between the magnet 3 and the bit 6, which can adjust the magnetic strength between the bit 6 and the magnet 3, making it easier to replace the bit 6. The magnetic force adjustment mechanism 5 and the rear magnetic conductive structure are respectively distributed at both ends of the magnet 3, so that the magnetic flux lines of the magnet 3 are distributed as much as possible toward the tip of the bit 6, thereby improving the nail support effect.
[0038] The present invention can ensure that the screwdriver bit has a relatively ideal nail supporting effect, and the adsorption force between the screwdriver bit and the end face of the internal magnet can be adjusted as needed, so as to ensure that the screwdriver bit can be easily and conveniently replaced.
[0039] The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.
Claims
1. A large magnetic tool head extension rod with a magnet end surface suction adjustment structure, characterized in that: It comprises a magnet (3), a connecting rod sleeve (4), a magnetic force adjustment structure (5) and a rear magnetic conductive structure, wherein the magnetic force adjustment structure (5), the magnet (3) and the rear magnetic conductive structure are sequentially arranged inside the connecting rod sleeve (4), and the rear magnetic conductive structure is adsorbed on the end of the magnet (3); The magnetic force adjustment structure (5) is located between the magnet (3) and the connected screwdriver bit; The magnetic force adjustment structure (5) is one of a thin sheet (5a), a circular ring, and a structure combining a thin sheet (5a) and a circular ring.
2. The large magnetic tool head extension rod with a magnet end surface suction force adjustment structure according to claim 1 is characterized in that: The connecting rod sleeve (4) is made of non-magnetic material.
3. The large magnetic tool head extension rod with a magnet end surface suction force adjustment structure according to claim 1 or 2, characterized in that: The connecting rod sleeve (4) comprises a screwdriver bit connection hole (41), an intermediate accommodating hole (42), and a connecting rod handle connection hole (43) arranged in sequence. The cross section of the intermediate accommodating hole (42) is circular, and the diameter of the intermediate accommodating hole (42) is not less than the maximum diameter of the screwdriver bit connection hole (41) and not less than the minimum diameter of the connecting rod handle connection hole (43).
4. The large magnetic tool head extension rod with a magnet end surface suction force adjustment structure according to claim 1 or 2, characterized in that: The cross-sections of the bit connection hole (41) and the connecting rod handle connection hole (43) are both regular polygons.
5. The large magnetic tool head extension rod with a magnet end surface suction force adjustment structure according to claim 3, characterized in that: When the magnetic force regulating structure (5) is a thin sheet (5a), the thin sheet (5a) is one of a non-magnetic sheet, an iron sheet, or a nickel sheet.
6. The large magnetic tool head extension rod with a magnet end surface suction force adjustment structure according to claim 3, characterized in that: When the magnetic force regulating structure (5) is a circular ring, the circular ring is one of a right-angled circular ring (5c), a circular ring with an inner bevel (5b), or a circular ring (5d) with a circular cross section, and the inner bevel contacts the chamfer of the tail of the connected screwdriver.
7. The large magnetic tool head extension rod with a magnet end surface suction force adjustment structure according to claim 6, characterized in that: When the magnetic force regulating structure (5) is a structure in which a thin sheet (5a) and a circular ring are combined, the thin sheet (5a) and the circular ring are an integrated structure with equal outer diameters or a concentric stacking structure of the thin sheet (5a) and the circular ring with equal outer diameters, and the thin sheet (5a) is placed between the magnet (3) and the circular ring.
8. The large magnetic tool head extension rod with a magnet end surface suction force adjustment structure according to claim 3, characterized in that: The connecting rod handle comprises a small-head handle section (1) and a large-head handle section (2) plugged into the connecting rod handle connection hole (43); the minimum diameter of the large-head handle section (2) is not less than the diameter of the connected magnet (3).
9. The large magnetic tool head extension rod with a magnet end surface suction force adjustment structure according to claim 6 or 7, characterized in that: The circular ring (5d) with a circular cross section is an open ring or a closed ring structure.
10. The large magnetic tool head extension rod with a magnet end surface suction force adjustment structure according to claim 8, characterized in that: The rear magnetic conductive structure comprises a large head handle section (2), and the large head handle section (2) is made of a magnetic conductive material.