Tool for working in narrow and small space

Abstract

The invention relates to the technical field of mechanical assembly and maintenance tools, and provides a narrow space operation tool which comprises a right-angle transmission head and a first telescopic output assembly. The right-angle transmission head comprises an input shaft and an output shaft which are perpendicular to each other and are in transmission connection. The first telescopic output assembly comprises a rod body and a sliding sleeve which can axially and slidably sleeve the rod body. The rear end of the rod body is connected with an output shaft, and the front end of the rod body is provided with a bit interface; and a double-position locking mechanism is arranged between the rod body and the sliding sleeve and is used for selectively locking the sliding sleeve at a retraction position or an extension position relative to the rod body. And an insulating sheath is arranged outside a flexible transmission core of the flexible extension shaft. According to the narrow space operation tool, the power output direction can be changed through the right-angle transmission head, the sliding sleeve of the first telescopic output assembly can be locked at the extending position relative to the rod body in a sliding mode, precision and stability of screw adsorption and conveying are guaranteed, and the risk that screws fall off is avoided.

Description

Technical Field

[0001] This invention relates to the field of mechanical assembly and maintenance tools, and more specifically, to a tool for working in confined spaces. Background Technology

[0002] In power systems (such as switchgear, load distribution panels, and current transformer terminal boxes), aerospace equipment, and complex machinery interiors, there are numerous bolt tightening and maintenance operations that need to be performed in extremely confined, crowded, and often near-electrical environments. These spaces typically have narrow openings, contain obstacles such as busbars and wiring harnesses, and the target bolts are often located in deep holes or blind spots that are difficult to see directly.

[0003] Currently, maintenance personnel often attempt the following methods, but all have significant limitations: 1. Using extension rods or universal joints: Rigid extension rods significantly increase the size of the tool head, easily interfering with surrounding equipment and failing to reach deep cavities. Universal joints experience a sharp decrease in torque transmission efficiency under bending paths, easily causing sleeve slippage, damaging bolt threads, and posing a risk of detachment. 2. Using small right-angle wrenches or custom-made tools: Fixed-size right-angle wrenches are difficult to adapt to bolts of different depths and angles, and custom-made tools are expensive and lack versatility. 3. Manual operation: In extremely limited space, it may be necessary to operate barehanded or use unconventional tools, making it difficult to guarantee assembly quality, failing to achieve the required torque, and resulting in extremely low efficiency. 4. Safety issues: The metal parts of ordinary tools lack sufficient insulation protection near live equipment, easily leading to safety accidents.

[0004] In addition, existing magnetic tools often suffer from disordered magnetic field distribution when the magnetic bit is in close contact with the body of a large gearbox or when there are many surrounding metal parts. This can easily lead to accidental attraction or insufficient attraction, especially in deep hole environments where problems such as screws falling off halfway or failing to reach the target position are particularly likely to occur. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a tool for working in confined spaces, which aims to solve the problems existing in the prior art.

[0006] According to the present invention, a confined space operation tool is provided, which includes a right-angle transmission head and a first telescopic output component connected to the right-angle transmission head; The right-angle transmission head includes an input shaft and an output shaft that are perpendicular to each other and connected in transmission. The input shaft is used to connect a driving tool, and the output shaft has a hollow structure and a first non-circular inner hole. The first telescopic output assembly includes a rod and a sliding sleeve that is axially slidably fitted onto the rod; the rear end of the rod can be inserted into the first non-circular inner hole to achieve circumferential locking, and the front end of the rod is provided with a bit interface; a double-position locking mechanism is provided between the rod and the sliding sleeve to selectively lock the sliding sleeve in a retracted position or an extended position relative to the rod.

[0007] Preferably, the right-angle transmission head further includes a housing and a bevel gear pair disposed within the housing and meshing with each other, wherein the input shaft and the output shaft are connected by the bevel gear pair.

[0008] Preferably, the dual-position locking mechanism includes: two annular positioning grooves disposed on the outer wall of the rod, a radial hole disposed on the inner wall of the sliding sleeve, a locking member disposed in the radial hole, and an elastic element that provides radial inward pre-tightening force to the locking member; when the sliding sleeve slides to the point where the radial hole aligns with either of the annular positioning grooves, the locking member is partially engaged in the annular positioning groove under the action of the elastic element.

[0009] Preferably, the locking element is a steel ball, and the elastic element is a cylindrical helical compression spring.

[0010] Preferably, a permanent magnet is provided at the bit interface.

[0011] Preferably, it further includes a flexible extension shaft, the flexible extension shaft comprising: A flexible transmission core, which is made of at least two layers of metal wires wound in opposite directions; An insulating sheath covers the outside of the flexible transmission core; The proximal connector is fixedly connected to one end of the flexible transmission core and has a second non-circular inner hole for detachable connection with the output shaft or the first telescopic output assembly. The second telescopic output component is fixedly connected to the other end of the flexible transmission core, and the second telescopic output component has the same structure as the first telescopic output component.

[0012] Preferably, the first non-circular inner hole, the second non-circular inner hole, and the rear end cross-section of the rod are polygonal.

[0013] Preferably, the insulating sheath includes a circular sheath tube body and a plurality of umbrella-shaped rings disposed on the circular sheath tube body, the plurality of umbrella-shaped rings being evenly distributed along the axis of the circular sheath tube body.

[0014] Preferably, the insulating sheath is made of resin.

[0015] Preferably, the insulating sheath is integrally manufactured by injection molding.

[0016] The confined space operation tool provided by this invention features a right-angle transmission head that allows for changes in power output direction. The sliding sleeve of the first telescopic output component can be slidably locked in its extended position relative to the rod body, significantly optimizing the magnetic field environment during deep hole operations. This ensures precise and stable screw adsorption and transport, avoiding the risk of screws falling off. The flexible transmission core of the flexible extension shaft enables stable torque transmission under complex paths, and the insulating sleeve provides comprehensive electrical isolation, improving safety during maintenance operations in confined spaces. Attached Figure Description

[0017] The above and other objects, features and advantages of the present invention will become clearer from the following description of embodiments of the invention with reference to the accompanying drawings.

[0018] Figure 1 A three-dimensional structural diagram of the connection state between the right-angle transmission head and the first telescopic output component in a confined space working tool according to an embodiment of the present invention is shown.

[0019] Figure 2 A three-dimensional structural schematic diagram of a right-angle transmission head in a confined space operation tool according to an embodiment of the present invention is shown.

[0020] Figure 3 A schematic diagram of the structure of the sliding sleeve of the first telescopic output component in the confined space working tool according to an embodiment of the present invention is shown, with the sleeve locked in the extended position.

[0021] Figure 4 for Figure 3 A magnified view of a portion of point A in the middle.

[0022] Figure 5 A schematic diagram of the structure of the sliding sleeve of the first telescopic output component in a confined space working tool according to an embodiment of the present invention is shown, with the sleeve locked in the retracted position.

[0023] Figure 6 A three-dimensional structural schematic diagram of a flexible extension shaft in a confined space operation tool according to an embodiment of the present invention is shown.

[0024] Figure 7 A longitudinal sectional view of a flexible extension shaft in a confined space working tool according to an embodiment of the present invention is shown.

[0025] In the figure: 1. Right-angle transmission head; 11. Input shaft; 12. Output shaft; 121. First non-circular inner hole; 13. Housing; 2. First telescopic output assembly; 21. Rod body; 211. Bit interface; 212. Annular positioning groove; 22. Sliding sleeve; 221. Radial hole; 222. Locking element; 223. Elastic element; 3. Flexible extension shaft; 31. Flexible transmission core; 32. Insulating sleeve; 321. Circular sheath tube body; 322. Umbrella-shaped ring; 33. Proximal end connector; 331. Second non-circular inner hole; 34. Second telescopic output assembly. Detailed Implementation

[0026] Various embodiments of the invention will now be described in more detail with reference to the accompanying drawings. In the various drawings, the same elements are indicated by the same or similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale.

[0027] This invention provides a tool for working in confined spaces, see [link / reference]. Figures 1 to 5 The confined space working tool includes a right-angle transmission head 1 and a first telescopic output assembly 2 connected to the right-angle transmission head 1. The right-angle transmission head 1 includes an input shaft 11 and an output shaft 12 that are perpendicular to each other and connected in transmission. The input shaft 11 is used to connect a driving tool, and the output shaft 12 is a hollow structure with a first non-circular inner hole 121. The first telescopic output assembly 2 includes a rod 21 and a sliding sleeve 22 that is axially slidably sleeved on the rod 21. The rear end of the rod 21 can be inserted into the first non-circular inner hole 121 to achieve circumferential locking, and the front end of the rod 21 is provided with a bit interface 211. A double-position locking mechanism is provided between the rod 21 and the sliding sleeve 22 to selectively lock the sliding sleeve 22 in a retracted position or an extended position relative to the rod 21.

[0028] Specifically, in this confined space operation tool, the input shaft 11 of the right-angle transmission head 1 can be connected to the power output end of an electric rotary drive tool such as an electric wrench. The right-angle transmission head 1 transmits the power of the electric rotary drive tool and changes the direction of power transmission. The rear end of the rod 21 of the first telescopic output assembly 2 is connected to the output shaft 12 of the right-angle transmission head 1, and the bit interface 211 at the front end of the rod 21 is connected to a magnetic bit for tightening bolts. When the electric rotary drive tool is started, the right-angle transmission head 1 can transmit power to the magnetic bit connected to the front end of the rod 21 of the first telescopic output assembly 2, so as to perform bolt disassembly and assembly operations in confined spaces through the first telescopic output assembly 2. When encountering situations requiring insertion into nut grooves or slightly deeper holes, or when there are large gearboxes or numerous metal parts around the workspace, the sliding sleeve 22 of the first telescopic output assembly 2 can be slid towards the front end of the rod 21 and locked in the extended position relative to the rod 21. This allows the sliding sleeve 22 to be fitted over the magnetic bit, preventing the magnetic bit and the attracted bolt from accidentally falling off due to the surrounding magnetic attraction.

[0029] The right-angle transmission head 1 also includes a housing 13 and a bevel gear pair disposed within the housing 13 and meshing with each other. The input shaft 11 and the output shaft 12 are connected by the bevel gear pair. Specifically, the housing 13 includes two cylindrical sections arranged perpendicularly to each other. The bevel gear pair includes a pair of meshing bevel gears, which are located at the junction of the two cylindrical sections. One end of the input shaft 11 and the other end of the output shaft 12 within the housing 13 are respectively connected to the two bevel gears of the bevel gear pair, achieving torque transmission in the vertical direction. In use, one hand can hold the housing of the right-angle transmission head 1, while the other hand holds the driving tool for operation. The bevel gear pair has high transmission efficiency, a mature and reliable structure, and can withstand large operating torques, ensuring effective and stable power conversion from the driving tool to the working end. In specific implementation, the input shaft 11 and the output shaft 12 are supported in the housing 13 by rolling bearings. Figure 2 As shown, in this embodiment, the end of the input shaft 11 located outside the housing 13 is a rod-shaped structure with a regular hexagonal cross-section. A permanent magnet can be provided in the first non-circular inner hole 121 on the output shaft 12 to ensure a strong adsorption force when connecting the rod 21 of the first telescopic output assembly 2, preventing it from falling off during operation.

[0030] Further, in the first telescopic output assembly 2, the dual-position locking mechanism includes: two annular positioning grooves 212 disposed on the outer wall of the rod 21, a radial hole 221 disposed on the inner wall of the sliding sleeve 22, a locking member 222 disposed in the radial hole 221, and an elastic element 223 providing radial inward preload to the locking member 222; when the sliding sleeve 22 slides until the radial hole 221 aligns with either of the annular positioning grooves 212, the locking member 222 partially engages with the annular positioning groove 212 under the action of the elastic element 223. In this embodiment, the locking member 222 is a steel ball, and the elastic element 223 is a cylindrical helical compression spring. In specific implementation, the radial hole 221 can be drilled radially through the wall of the sliding sleeve 22 using a drill bit, with internal threads machined at the outer end of the through hole, and a steel column and a miniature cylindrical helical compression spring are sequentially placed in the through hole, and finally sealed from the outside with a set screw. When the sliding sleeve 22 is pulled to align with a certain annular positioning groove 212, the elastic force of the cylindrical helical compression spring presses the steel ball into the annular positioning groove 212, achieving locking. Both the steel column and the cylindrical helical compression spring are made of GCr15 bearing steel, ensuring a clear feel even after tens of thousands of extensions and retractions. Figure 3 and Figure 5 The diagrams show the sliding sleeve 22 locked in the extended and retracted positions relative to the rod 21. This dual-position locking mechanism features a simple, durable, and low-cost mechanical structure. The locking and unlocking actions are clearly tactile (a "click" sound and changes in resistance), perfectly meeting the need for status operation and confirmation without visual assistance in dark environments, greatly improving operational reliability and user experience.

[0031] Furthermore, a permanent magnet is provided at the bit interface 211. In a specific implementation, the permanent magnet can be made of N52 grade sintered neodymium iron boron high-strength magnet, which is embedded in the bit interface 211. The permanent magnet can provide a strong magnetic attraction force to the bit set on the bit interface 211, thereby better attracting and fixing the bolt to be tightened and preventing it from falling off during the process of being fed into the deep hole.

[0032] This confined space operation tool also includes a flexible extension shaft 3, see [link / reference] Figure 6 and Figure 7The flexible extension shaft 3 includes: a flexible transmission core 31, which is formed by winding at least two layers of metal wires in opposite directions; an insulating sheath 32, which covers the outside of the flexible transmission core 31; a proximal connector 33, which is fixedly connected to one end of the flexible transmission core 31 and has a second non-circular inner hole 331 for detachable connection with the output shaft 12 or the first telescopic output assembly 2; and a second telescopic output assembly 34, which is fixedly connected to the other end of the flexible transmission core 31, and the second telescopic output assembly 34 has the same structure as the first telescopic output assembly 2.

[0033] Specifically, the flexible transmission core 31 can be composed of a central steel wire core, a middle layer of clockwise wound steel wire, and an outer layer of counterclockwise wound steel wire. This structure of the flexible transmission core 31 effectively suppresses the "whipping" effect and loose deformation generated by a single layer of steel wire rope during torsion. When the tool must bend significantly to reach the target, this design can significantly reduce torque attenuation and angular jitter, ensuring sufficient and stable rotational force output from the power source to the working end, thereby reliably tightening or loosening bolts. The distal end of the flexible transmission core 31 is provided with a second telescopic output assembly 34, which has the same structure as the first telescopic output assembly 2, and can also prevent the magnetic bit and the attracted bolt from accidentally falling off due to the surrounding magnetic attraction force.

[0034] The flexible extension shaft 3 can be modularly combined with the right-angle transmission head 1, enabling it to handle extremely complex paths. This upgrades the tool from a simple "right-angle turn" capability to one that can bend arbitrarily and bypass obstacles. The tool is no longer limited to straight lines or fixed-angle channels; it can traverse complex S-shaped and U-shaped paths like a "robotic arm" or a "snake," reaching ultra-deep cavities and multi-dead-angle work points that traditional rigid tools simply cannot access, solving the fundamental problem of "inaccessibility." For example, when a bolt is located deep within a cabinet and there is an S-shaped bend in front, the right-angle transmission head 1 and the flexible extension shaft 3 can be used in combination, allowing the tool to bypass obstacles like a "robotic arm" and precisely reach the work point, solving the dilemma that traditional rigid tools are completely unable to operate.

[0035] Furthermore, the first non-circular inner hole 121, the second non-circular inner hole 331, and the rear end cross-section of the rod 21 are polygonal. In this embodiment, the first non-circular inner hole 121, the second non-circular inner hole 331, and the rear end cross-section of the rod 21 are all regular hexagons, and all connection interfaces adopt this standard hexagonal specification. The hexagonal interface has both good torque transmission capability and moderate manufacturing precision requirements, and is a common standard in the tool industry. This design ensures compatibility and interchangeability between various modules of the tool, and also facilitates use with commonly available hexagonal bits and sockets, reducing the cost of special accessories for users. Among them, when the proximal connector 33 of the flexible extension shaft 3 is connected to the output shaft 12 of the right-angle transmission head 1 or the first telescopic output assembly 2, a regular hexagonal connecting rod can be used to achieve the connection. It can be understood that the proximal connector 33 can be set as a rod-shaped structure with the same rear end cross-section as the rod 21 of the first telescopic output assembly 2.

[0036] In this embodiment, in addition to the permanent magnet at the bit interface 211, permanent magnets are also provided at the first non-circular inner hole 121 and the second non-circular inner hole 331 to enhance the axial attraction when the modules are docked, prevent the first telescopic output component 2 and the flexible extension shaft 3 from accidentally coming loose due to their own weight or operational vibration, and improve the stability of operation under complex postures.

[0037] Furthermore, the insulating sleeve 32 includes a circular sleeve tube body 321 and a plurality of umbrella-shaped rings 322 disposed on the circular sleeve tube body 321. The plurality of umbrella-shaped rings 322 are evenly distributed along the axis of the circular sleeve tube body 321. Specifically, both ends of the circular sleeve tube body 321 extend to the proximal end connectors 33 at both ends of the flexible transmission core 31 and the rear end position of the rod 21 of the second telescopic output assembly 34 to achieve full coverage of the flexible transmission core 31. By providing a plurality of umbrella-shaped rings 322 evenly distributed along its axial extension direction on the circular sleeve tube body 321, the creepage distance on the surface of the insulating sleeve 32 is effectively extended. When the tool is operating in an electrical cabinet with high humidity, condensation, or dust pollution, this design can significantly suppress leakage creepage of current along the insulation surface, preventing surface flashover or breakdown, and is a key safety design for dealing with complex near-electrical conditions. Meanwhile, the umbrella-shaped ring 322 structure provides additional structural strength and radial support to the circular sheath tube body 321. When tools pass through narrow spaces or scrape against the inner wall of the cabinet, the raised umbrella-shaped ring 322 can disperse contact stress and friction, preferentially bearing wear, thereby more effectively protecting the internal flexible transmission core 31 and the circular sheath tube body 321, extending the overall service life. In addition, when the flexible extension shaft 3 needs to bend to adapt to the path, the evenly distributed umbrella-shaped ring 322 structure can deform uniformly with the circular sheath tube body 321 without wrinkling or excessive stretching, avoiding the risk of thin walls or cracks in the insulating sheath 32 at the bending point, ensuring the continuity and consistency of insulation protection under dynamic bending conditions.

[0038] Furthermore, the insulating sleeve 32 is made of resin; it is integrally manufactured using injection molding. Resin materials (such as epoxy resin, polyamide, polycarbonate, etc.) inherently possess high resistivity, high dielectric strength, and low dielectric loss, providing a solid material foundation for the insulating sleeve 32. This ensures effective current isolation in near-electric environments such as power grids, preventing the risk of electric shock. Resin materials typically combine good mechanical strength, toughness, and wear resistance, enabling the insulating sleeve 32 to withstand mechanical stresses such as bending and friction from tools in confined spaces. It also exhibits resistance to moisture, chemical corrosion, and weathering, adapting to complex environments such as condensation and oil contamination within electrical cabinets, ensuring long-term reliability. Integral injection molding fundamentally avoids defects such as seams, bubbles, or uneven thickness that may occur with processes like winding, coating, or splicing. This ensures that the insulating sleeve 32 has continuous and uniform insulation performance and wall thickness in all parts, eliminating localized weak points in insulation caused by manufacturing processes and greatly improving the safety level. In practice, the dried resin material can be added to an injection molding machine, heated and melted, and then injected into a pre-designed mold cavity. The mold cavity precisely replicates the shape of the circular sheath tube body 321 and all the umbrella-shaped rings 322. After the melt cools and solidifies in the mold cavity, it is demolded, resulting in an insulating sheath 32 with a complete structure, accurate dimensions, and uniform insulation performance. It is then fitted onto the outside of the flexible transmission core 31, and both ends can be connected to the proximal connector 33 and the rod 21 of the second telescopic output assembly 34 by adhesive.

[0039] In summary, the confined space operation tool provided by this invention features a right-angle transmission head that allows for changes in power output direction. The sliding sleeve of the first telescopic output component can be slidably locked in its extended position relative to the rod body, significantly optimizing the magnetic field environment during deep hole operations. This ensures precise and stable screw adsorption and transport, avoiding the risk of screws falling off. The flexible transmission core of the flexible extension shaft enables stable torque transmission under complex paths, and the insulating sleeve provides comprehensive electrical isolation, improving safety during maintenance operations in confined spaces.

[0040] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0041] Finally, it should be noted that the above embodiments are merely examples for clearly illustrating the present invention and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A tool for working in confined spaces, characterized in that, It includes a right-angle drive head and a first telescopic output assembly connected to the right-angle drive head; The right-angle transmission head includes an input shaft and an output shaft that are perpendicular to each other and connected in transmission. The input shaft is used to connect a driving tool, and the output shaft has a hollow structure and a first non-circular inner hole. The first telescopic output assembly includes a rod and a sliding sleeve that is axially slidably fitted onto the rod; the rear end of the rod can be inserted into the first non-circular inner hole to achieve circumferential locking, and the front end of the rod is provided with a bit interface; a double-position locking mechanism is provided between the rod and the sliding sleeve to selectively lock the sliding sleeve in a retracted position or an extended position relative to the rod.

2. The confined space operation tool according to claim 1, characterized in that, The right-angle transmission head also includes a housing and a bevel gear pair disposed within the housing and meshing with each other, wherein the input shaft and the output shaft are connected by the bevel gear pair.

3. The confined space operation tool according to claim 1, characterized in that, The dual-position locking mechanism includes: two annular positioning grooves disposed on the outer wall of the rod, a radial hole disposed on the inner wall of the sliding sleeve, a locking member disposed in the radial hole, and an elastic element that provides radial inward pre-tightening force to the locking member; when the sliding sleeve slides to the point where the radial hole aligns with either of the annular positioning grooves, the locking member is partially engaged in the annular positioning groove under the action of the elastic element.

4. The confined space operation tool according to claim 3, characterized in that, The locking element is a steel ball, and the elastic element is a cylindrical helical compression spring.

5. The confined space operation tool according to claim 1, characterized in that, A permanent magnet is provided at the bit interface.

6. The confined space operation tool according to any one of claims 1 to 5, characterized in that, It also includes a flexible extension shaft, which comprises: A flexible transmission core, which is made of at least two layers of metal wires wound in opposite directions; An insulating sheath covers the outside of the flexible transmission core; The proximal connector is fixedly connected to one end of the flexible transmission core and has a second non-circular inner hole for detachable connection with the output shaft or the first telescopic output assembly. The second telescopic output component is fixedly connected to the other end of the flexible transmission core, and the second telescopic output component has the same structure as the first telescopic output component.

7. The confined space operation tool according to claim 6, characterized in that, The first non-circular inner hole, the second non-circular inner hole, and the rear end cross-section of the rod are polygonal.

8. The confined space operation tool according to claim 6, characterized in that, The insulating sheath includes a circular sheath tube body and a plurality of umbrella-shaped rings disposed on the circular sheath tube body, the plurality of umbrella-shaped rings being evenly distributed along the axis of the circular sheath tube body.

9. The confined space operation tool according to claim 6, characterized in that, The insulating sheath is made of resin.

10. The confined space operation tool according to claim 9, characterized in that, The insulating sheath is integrally manufactured using an injection molding process.

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