Screw fastening torque increasing device

Abstract

The invention provides a screw fastening torque increasing device. The device comprises a shell with a containing cavity. The cam assembly is rotatably arranged on the shell and is used for inputting torque; the output component is rotatably arranged in the shell and is used for outputting torque to fasten the screw; the deformation transmission wheel is fixed in the shell; the cam assembly comprises a driving cam arranged on the inner side of the deformation transmission wheel. The output component is arranged on the outer side of the deformation transmission wheel in a surrounding mode. The inner circumferential face of the deformation transmission wheel makes contact with the driving cam, and a plurality of protrusions arranged in a circumferential array are arranged on the outer circumferential face of the deformation transmission wheel. The output component comprises a force transmission structure which is correspondingly matched with the bulge; and the deformation transmission wheel is configured to outwards push the deformation transmission wheel in the radial direction of the deformation transmission wheel to generate radial deformation when the driving cam rotates, so that the bulge is driven to be in contact with a force transmission structure on the output component, and thrust is transmitted to the output component to drive the output component to rotate for screw fastening.

Description

Technical Field

[0001] This invention relates to the field of equipment assembly technology. More specifically, it relates to a screw tightening torque-increasing device. Background Technology

[0002] In mechanical assembly, equipment maintenance, and installation work in specific fields, screw connections are one of the most common fastening methods. Ensuring that the screws reach the specified preload is key to guaranteeing the reliability and safety of the connection, which usually requires applying sufficient tightening torque.

[0003] Currently, for screw tightening operations in conventional spaces, those skilled in the art generally use manual wrenches or power tools (such as electric or pneumatic screwdrivers). When greater torque is required, the most direct and effective method is to increase the lever arm, for example: 1. using a longer extension bar or wrench handle; 2. replacing it with a ratchet wrench with a larger transmission ratio; 3. directly using a large power tool with higher output torque. However, in practical applications, there are many compact and tightly arranged working conditions where the operating space is extremely small and limited (e.g., inside deep holes, between dense pipe rows, inside equipment compartments, etc.). In these confined spaces, the aforementioned conventional torque-increasing methods all face insurmountable obstacles such as spatial interference, insufficient torque, and operational difficulties. To solve these problems, existing technologies include impact tools (impact screwdrivers) or planetary gear torque-increasing wrenches, but impact tools have the drawback of being difficult to control, and planetary gear torque-increasing wrenches have the problems of large radial dimensions and limited applicability in confined spaces. Summary of the Invention

[0004] The purpose of this invention is to provide a screw tightening torque-increasing device to solve at least one of the above-mentioned technical problems.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a screw tightening torque-increasing device, comprising: A shell with a receiving cavity; A rotatable cam assembly mounted on the housing is used for inputting torque; A rotatable output component disposed within the housing for outputting torque to tighten the screw; and Deformable transmission wheel fixed inside the outer casing; The cam assembly includes a drive cam disposed inside the deformation transmission wheel; the output component is disposed around the outside of the deformation transmission wheel; the inner circumferential surface of the deformation transmission wheel contacts the drive cam, and the outer circumferential surface is provided with a plurality of protrusions arranged in a circular array; the output component includes a force transmission structure that corresponds to and cooperates with the protrusions. The deformable transmission wheel is configured such that when the drive cam rotates, it pushes the deformable transmission wheel radially outward, causing the deformable transmission wheel to deform radially. This causes the protrusion to contact the force transmission structure on the output component and transmits the thrust to the output component, driving the output component to rotate for screw tightening.

[0006] In a preferred embodiment, the rotation angle of the drive cam is greater than the rotation angle of the output component.

[0007] A preferred embodiment is that the housing includes a shell with an opening at one end and a bottom seal fixed to the opening end of the shell; the bottom seal and the shell enclose a receiving cavity; a through hole is formed on the bottom seal for a screw to pass through; and the shell includes an opening for a cam assembly to extend out of the receiving cavity.

[0008] A preferred embodiment is that the output component includes an output element for engaging with a screw and a plurality of steel balls arranged in a circular array and fixed to the inner circumferential surface of the output element by a fastener; all the steel balls form the force transmission structure; and the output element has a fastening output interface for engaging with the screw.

[0009] A preferred embodiment is that the cross-section of the drive cam is elliptical.

[0010] The preferred embodiment is that the deformable transmission wheel is a thin-walled rotary structure, and its upper surface is fixed to the inner surface of the outer shell; the protrusion is an arc-shaped columnar protrusion, and the number of the protrusions is two fewer than the number of the steel balls in a single circumferential array.

[0011] In a preferred embodiment, the screw tightening torque-increasing device further includes a sliding pad, which is installed between the contact interface between the output component and the deformation transmission wheel, and the sliding pad is fixed to the output component; through the sliding pad, the output component can slide relative to the deformation transmission wheel.

[0012] A preferred embodiment is that a first rotating track is provided between the bottom seal and the output component; a second rotating track is provided between the housing and the output component; and a third rotating track is provided between the housing and the drive cam.

[0013] A preferred embodiment is that the bottom annular surface of the bottom seal is provided with a magnetic attraction component, which is used to adhere to the external workpiece during screw tightening operations to keep the housing stationary.

[0014] In a preferred embodiment, the drive cam extends from the opening to the outside of the housing; the cam assembly also includes a handle located outside the housing and connected to the drive cam.

[0015] The beneficial effects of this invention are as follows: This invention provides a screw tightening torque-enhancing device comprising a housing with a receiving cavity; an output component rotatably disposed within the housing for outputting torque to tighten screws; a cam assembly rotatably disposed on the housing for inputting torque; and a deformable transmission wheel fixed within the housing; the cam assembly includes a drive cam disposed inside the deformable transmission wheel; the output component is disposed around the outside of the deformable transmission wheel; the inner circumferential surface of the deformable transmission wheel contacts the drive cam, and the outer circumferential surface has a plurality of protrusions arranged in a circular array; the output component includes a force-transmitting structure corresponding to and cooperating with the protrusions; the deformable transmission wheel is configured such that when the drive cam rotates, it pushes the deformable transmission wheel radially outward along the deformable transmission wheel, causing the deformable transmission wheel to deform radially, thereby driving the protrusions to contact the force-transmitting structure on the output component and transmitting the thrust to the output component to drive the output component to rotate for screw tightening. This device highly integrates the drive, transmission, and output components within the same housing. This compact design eliminates the need for external extension arms, making it suitable for confined spaces with strict radial and axial space constraints, such as deep holes, dense pipe arrays, and equipment cavities. It solves the problem of traditional wrenches or power tools being unable to complete tasks due to spatial interference. Furthermore, the device provides a mechanism that converts operator-input rotational motion into output rotation via a drive cam and a deformable transmission wheel, effectively amplifying torque without relying on external extension arms. This addresses the challenge of tightening screws to the specified torque in confined spaces. Attached Figure Description

[0016] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0017] Figure 1 A schematic diagram of the screw tightening torque-increasing device of the present invention is shown.

[0018] Figure 2 A cross-sectional view of the screw tightening torque-increasing device of the present invention is shown.

[0019] Figure 3A and Figure 3B A schematic diagram of the output component structure of the screw tightening torque-increasing device of the present invention is shown.

[0020] Figure 4A and Figure 4B A schematic diagram of the deformable transmission wheel structure of the screw tightening torque-increasing device of the present invention is shown.

[0021] Figure 5A and Figure 5B A schematic diagram of the structure of the deformable transmission wheel of the present invention after it has been pushed and deformed is shown.

[0022] Figure 6 A schematic diagram showing the screw tightening torque-increasing device of the present invention in use is provided.

[0023] Figure 7 The diagram shows a cross-sectional view of the output component, the deformable transmission wheel, and the cam assembly of the screw tightening torque-increasing device of the present invention.

[0024] Figure 8 This diagram illustrates one of the motion steps of a screw tightening torque-increasing device according to the present invention.

[0025] Figure 9 The second schematic diagram shows the motion steps of a screw tightening torque-increasing device according to the present invention. Detailed Implementation

[0026] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention.

[0027] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0028] Technologies and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such technologies and equipment should be considered part of the specification.

[0029] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0030] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0031] This invention provides a screw tightening torque amplification device that can operate effectively within limited radial and axial space. Without relying on an externally extended lever arm, it effectively amplifies torque through its internal structure, thereby solving the problem of screws being difficult to tighten to the specified torque in confined spaces. Combined with... Figures 1 to 9As shown, the screw tightening torque-enhancing device specifically includes: a housing with a receiving cavity; an output component 3 rotatably disposed within the housing for outputting torque to tighten the screw 9; a cam assembly 5 rotatably disposed on the housing for inputting torque; and a deformable transmission wheel 4 fixed within the housing. The cam assembly 5 includes a drive cam 51 disposed inside the deformable transmission wheel 4; the output component 3 is disposed around the outside of the deformable transmission wheel 4; the inner circumferential surface of the deformable transmission wheel 4 contacts the drive cam 51, and the outer circumferential surface is provided with a plurality of protrusions 41 arranged in a circular array. The output component 3 includes a force-transmitting structure corresponding to and cooperating with the protrusions 41. The deformable transmission wheel 4 is configured such that when the drive cam 51 rotates under external force, it pushes the deformable transmission wheel 4 radially outward along the deformable transmission wheel 4, causing the deformable transmission wheel 4 to deform radially, thereby driving the protrusions 41 to contact the force-transmitting structure on the output component 3 and transmitting the thrust to the output component 3 to drive the output component 3 to rotate, thus tightening the screw 9. When the drive cam 51 rotates under external force, it radially presses the deformable transmission wheel 4 outward, causing a localized bulge deformation on the outer circumferential surface of the deformable transmission wheel 4. This localized bulge deformation causes the protrusions 41 on its outer circumferential surface to sequentially contact the force transmission structure on the output component 3, pushing the output component 3 to rotate around its own axis, thereby outputting the torque for tightening the screw 9. This device combines small size with high output torque, effectively completing screw tightening torque amplification within limited radial and axial space. It achieves effective torque amplification through its internal structure without relying on external extension arms. Furthermore, its purely mechanical structure ensures reliable operation, is not limited by power supply, and is suitable for various on-site assembly and maintenance environments. It fundamentally solves the problem that in compact and densely arranged working conditions, insufficient operating space prevents the use of conventional torque amplification methods (extended rods, high-ratio wrenches, large power tools), making it difficult to tighten screws to the specified torque.

[0032] In one specific embodiment, the rotation angle of the drive cam 51 is greater than the rotation angle of the output component 3 to achieve deceleration and torque increase. The input rotation angle of the drive cam 51 is greater than the output rotation angle of the output component 3, thereby achieving higher output torque with limited manual input, ensuring that the screw 9 meets the specified preload requirements. Furthermore, the torque transmission process of this device is smooth and controllable, avoiding the risk of thread damage due to torque overshoot caused by impact tools.

[0033] Regarding the specific structure of the outer casing, the outer casing includes a housing 1 with one end open and a bottom seal 2 fixed to the open end of the housing 1; the bottom seal 2 and the housing 1 enclose a receiving cavity; a through hole for a screw to pass through is formed on the bottom seal 2; the housing 1 includes an opening for a cam assembly 5 to extend out of the receiving cavity. The housing 1 and the bottom seal 2 are coaxially arranged.

[0034] In one specific embodiment, the output component 3 includes an output part 31 for engaging with the screw 9 and a plurality of steel balls 32 arranged in a circular array and fixed to the inner circumferential surface of the output part 31 by a fixing member 33; all the steel balls 32 form the force transmission structure; the output part 31 has a fastening output interface 311 for engaging with the screw 9. The output part 31, steel balls 32 and fixing member 33 are fixedly connected and rotate as a whole, that is, the output part 31, steel balls 32 and fixing member 33 form a completely fixed and rotating whole. The output part 31 and the fixing member 33 are both coaxially arranged with the outer shell. The fixing member 33 includes three sets of steel balls 32 arranged in a circular array along the axial direction of the outer shell, and the steel balls 21 are fixed to the output part 31 by the fixing member 33. The fastening output interface 311 can be designed in various forms as needed to be compatible with different screw head types and expand the applicable scenarios of the device. The cam assembly 5 is the torque input end of the fastening torque amplification device, and the operator holds the handle 52 of the cam assembly 5 to input torque. Output component 3 is a torque output end. The output part 31 of output component 3 can be used with different types of screws to complete the tightening action. This tightening torque amplification device can amplify the torque input from handle 52 to output torque from output component 31 through the cooperation of drive cam 51, deformable transmission wheel 4 and steel ball 32 inside the housing.

[0035] In one specific embodiment, the deformable transmission wheel 4 is a thin-walled rotary structure, i.e., the deformable transmission wheel 4 is a cylindrical component with a relatively thin wall thickness, which has good elasticity and can undergo radial deformation under the outward compression of the drive cam 51 located on its inner side. The upper surface of the deformable transmission wheel 4 is fixed to the inner surface of the outer shell; the protrusion 41 is an arc-shaped columnar protrusion. The deformable transmission wheel 4 is coaxially arranged with the outer shell. Moreover, the number of protrusions 41 is two less than the number of the single-circumferential array of steel balls 32. The drive cam 51 of the cam assembly 5 is located on the inner ring of the deformable transmission wheel 4. Based on the thin-walled characteristics of the deformable transmission wheel 4, the rotation of the drive cam 51 can drive the deformable transmission wheel 4 to deform as a whole.

[0036] Furthermore, the screw tightening torque-increasing device also includes a sliding pad 7, which is installed between the contact interface of the output member 31 and the deformable transmission wheel 4. The bottom surface of the sliding pad 7 is fixed to the output member 31, and the top surface of the sliding pad 7 contacts the deformable transmission wheel 4. By providing the sliding pad, the output member 31 can slide relative to the deformable transmission wheel 4. The contact surface of the deformable transmission wheel 4 can slide relative to the sliding pad 7, and the sliding pad 7 is used to constrain the normal degree of freedom of the contact surface of the deformable transmission wheel 4.

[0037] In one specific embodiment, a first rotating track 61 is provided between the bottom seal 2 and the output component 3; a second rotating track 62 is provided between the housing 1 and the output component 3; and a third rotating track 63 is provided between the housing 1 and the drive cam 51. The output component 3 is a single piece, clamped between the housing 1 and the bottom seal 2, and can rotate relative to the housing axis via the first and second rotating tracks 61 and 62. It is understood that all of the above rotating tracks are annular tracks. The horizontal cross-section of the drive cam 51 is elliptical. Figures 4A-5B As shown, under the external thrust of the drive cam 51, the horizontal cross-section of the deformable transmission wheel 4 changes from a circle to an ellipse. Furthermore, the drive cam 51 extends upwards from the opening to the outside of the housing 1; the cam assembly 5 also includes a handle 52 located outside the housing 1 and connected to the drive cam 51. The drive cam 51 and the handle 52 can be separate structures to accommodate the assemblability of the overall structure. The drive cam 51 is fixedly connected to the handle 52 and rotates together with the operator's rotational tightening action. The cam assembly 5 achieves rotational movement relative to the housing axis via the third rotational track 63.

[0038] In one specific embodiment, the bottom annular surface of the bottom seal 2 is provided with a magnetic attraction component, which is used to adhere to the external workpiece 8 during screw tightening operations to keep the housing stationary. The magnetic attraction component facilitates the device's adsorption and positioning on the external workpiece 8, enabling one-handed operation. Both the housing 1 and the bottom seal 2 are rotary structural components, one of each, and are relatively fixed and coaxially arranged. During screw tightening operations, neither the housing 1 nor the bottom seal 2 rotates.

[0039] The following is combined with Figures 6 to 9 The specific working process of the screw tightening torque-increasing device of the present invention is explained.

[0040] like Figure 6 and Figure 7 As shown, when the screw tightening torque-enhancing device of the present invention performs the screw 9 tightening operation, the input torque of the cam assembly 5 is transmitted to the screw tightening end of the output component 31 through the force transmission path of the deformable transmission wheel 4 and the output component 3. The upper surface of the deformable transmission wheel 4 is fixed to the housing 1 and does not rotate during the tightening process. More specifically, during the rotation of the drive cam 51 of the cam assembly 5, it pushes the deformable transmission wheel 4 to undergo local convex deformation. The protrusion 41 located at the convex deformation position on the deformable transmission wheel 4 contacts the steel balls 32 arranged in a circular array on the output component 3, transmitting the thrust to the output component 3. The output component 3 as a whole obtains the output torque, which completes the screw 9 tightening.

[0041] Figure 8 This illustrates the state of a typical motion step one. Figure 9The state of typical motion step two is shown. From typical motion step one to typical motion step two, the screw tightening torque-increasing device of the present invention completes one complete transmission cycle. The tightening motion process of the screw tightening torque-increasing device consists of the above-mentioned several repetitive transmission cycles. More specifically, Figure 8 In the typical motion step shown, the protrusion 411 of the deformable transmission wheel 4 contacts the steel ball 321 on the output component 31, and the deformation of the protrusion 411 is located at its highest radial point; the protrusion 412 on the deformable transmission wheel 4 begins to contact the steel ball 322 on the output component 31. As the drive cam 51 continues to rotate, the protrusion 411 on the deformable transmission wheel 4 disengages from the steel ball 321 on the output component 31; the protrusion 412 on the deformable transmission wheel 4 continues to contact the steel ball 322 on the output component 31, and the protrusion 412 on the deformable transmission wheel 4 continues to rise radially, pushing the output component 31 to rotate through the steel ball 322 on the output component 31. This continues until the protrusion 412 on the deformable transmission wheel 4 reaches its highest radial point, thus achieving the desired state. Figure 9 The typical motion step two states are shown.

[0042] exist Figure 9 In the typical motion step two state shown, the protrusion 412 on the deformable transmission wheel 4 contacts the steel ball 322 on the output component 31, and the deformation of the protrusion 412 is located at the highest point in the radial direction; the protrusion 413 on the deformable transmission wheel 4 begins to contact the steel ball 323 on the output component 31. At this time, the structural motion completes one cycle and begins to repeat the motion of typical motion step one to typical motion step two.

[0043] From the first to the second typical motion step described above, when the drive cam 51 rotates, it drives the output component 3 to rotate continuously. The rotation angle of the drive cam 51 is θ1, and the rotation angle of the output component 3 is θ2. The rotation angle θ1 of the drive cam 51 is much higher than the rotation angle θ2 of the output component 3, thereby creating a favorable deceleration and torque increase.

[0044] In summary, the present invention provides a screw tightening torque-enhancing device comprising a housing with a receiving cavity; an output component rotatably disposed within the housing for outputting torque to tighten screws; a cam assembly rotatably disposed on the housing for inputting torque; and a deformable transmission wheel fixed within the housing; the cam assembly includes a drive cam disposed inside the deformable transmission wheel; the output component is disposed around the outer side of the deformable transmission wheel; the inner circumferential surface of the deformable transmission wheel contacts the drive cam, and the outer circumferential surface is provided with a plurality of protrusions arranged in a circular array; the output component includes a force transmission structure corresponding to and cooperating with the protrusions; the deformable transmission wheel is configured such that when the drive cam rotates, it pushes the deformable transmission wheel radially outward, causing the deformable transmission wheel to deform radially, thereby driving the protrusions to contact the force transmission structure on the output component and transmitting the thrust to the output component to drive the output component to rotate for screw tightening. This device highly integrates the drive, transmission, and output components within the same housing. This compact design eliminates the need for external extension arms, making it suitable for confined spaces with strict radial and axial space constraints, such as deep holes, dense pipe arrays, and equipment cavities. It solves the problem of traditional wrenches or power tools being unable to complete tasks due to spatial interference. Furthermore, the device provides a mechanism that converts operator-input rotational motion into output rotation via a drive cam and a deformable transmission wheel, effectively amplifying torque without relying on external extension arms. This addresses the challenge of tightening screws to the specified torque in confined spaces.

[0045] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A screw tightening torque-increasing device, characterized in that, include: A shell with a receiving cavity; A rotatable cam assembly mounted on the housing is used for inputting torque; A rotatable output component located within the housing is used to output torque to tighten screws; as well as Deformable transmission wheel fixed inside the outer casing; The cam assembly includes a drive cam disposed inside the deformation transmission wheel; the output component is disposed around the outside of the deformation transmission wheel; the inner circumferential surface of the deformation transmission wheel contacts the drive cam, and the outer circumferential surface is provided with a plurality of protrusions arranged in a circular array; the output component includes a force transmission structure that corresponds to and cooperates with the protrusions. The deformable transmission wheel is configured such that when the drive cam rotates, it pushes the deformable transmission wheel radially outward, causing the deformable transmission wheel to deform radially. This causes the protrusion to contact the force transmission structure on the output component and transmits the thrust to the output component, driving the output component to rotate for screw tightening.

2. The screw tightening torque-increasing device according to claim 1, characterized in that, The rotation angle of the drive cam is greater than the rotation angle of the output component.

3. The screw tightening torque-increasing device according to claim 1, characterized in that, The housing includes a shell open at one end and a bottom seal fixed to the open end of the shell; the bottom seal and the shell enclose a receiving cavity; a through hole is formed on the bottom seal for a screw to pass through; the shell includes an opening for a cam assembly to extend out of the receiving cavity.

4. The screw tightening torque-increasing device according to claim 1, characterized in that, The output component includes an output element for engaging with a screw and a plurality of steel balls arranged in a circular array and fixed to the inner circumferential surface of the output element by a fastener; all the steel balls form the force transmission structure; and the output element has a fastening output interface for engaging with the screw.

5. The screw tightening torque-increasing device according to claim 1, characterized in that, The cross-section of the drive cam is elliptical.

6. The screw tightening torque-increasing device according to claim 4, characterized in that, The deformable transmission wheel is a thin-walled rotary structure, and its upper surface is fixed to the inner surface of the outer shell; the protrusion is an arc-shaped columnar protrusion, and the number of the protrusions is two fewer than the number of the steel balls in a single circumferential array.

7. The screw tightening torque-increasing device according to claim 4, characterized in that, The screw tightening torque-increasing device also includes a sliding pad, which is installed between the contact interface between the output component and the deformation transmission wheel, and the sliding pad is fixed to the output component; through the sliding pad, the output component can slide relative to the deformation transmission wheel.

8. The screw tightening torque-increasing device according to claim 3, characterized in that, A first rotating track is provided between the bottom seal and the output component; a second rotating track is provided between the housing and the output component; and a third rotating track is provided between the housing and the drive cam.

9. The screw tightening torque-increasing device according to claim 3, characterized in that, The bottom ring surface of the bottom seal is provided with a magnetic attraction component, which is used to attract the outer workpiece during screw tightening operations to keep the outer shell stationary.

10. The screw tightening torque-increasing device according to claim 3, characterized in that, The drive cam extends from the opening to the outside of the housing; the cam assembly also includes a handle located outside the housing and connected to the drive cam.

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