A screwdriver driving mechanism

Abstract

A screwdriver drive mechanism includes a base, a selection drive mechanism, and a selection drive member. The base includes a accommodating tube and two symmetrically arranged insert block accommodating chambers. The selection drive mechanism includes a central axis, two meshing blocks, and two restoring elastic members. The central axis includes a circle of teeth arranged on the outer circumferential surface. The meshing block includes an abutment surface and a tooth surface that meshes with the teeth of the central axis and is provided with teeth. When the restoring elastic member is compressed to a minimum length, the tooth surface is disengaged from the tooth portion. The selection drive member includes an arcuate drive portion and a connecting block. The arcuate drive portion is inserted between the accommodating tube and the central axis and is located between the two meshing blocks. When the arcuate drive portion rotates, it drives the meshing blocks to disengage from the tooth portion respectively. The screwdriver drive mechanism can increase its reliability in all aspects and is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of tool manufacturing, and in particular to a screwdriver driving mechanism. Background Art

[0002] The screwdriver tool used to drive screws and other fasteners usually includes a driving head and a handle such as a connecting rod. The driving head is used to connect with the fastener, and the handle is used to be held by the user to apply power. The driving head has different structures for different screws. For example, the driving head for driving screws has a straight, cross, Pozi, hexagonal, etc., and the driving head for driving nuts has various types of wrenches or sockets, etc.

[0003] In the known screwdriver drive structure, such as disclosed in US Pat. No. 6,658,970B2, the through slot for accommodating the moving end of the latch piece penetrates radially from the peripheral surface of the fixing seat to the inside, and the pivot hole for the lower side pivot of the latch piece is opened toward the front side of the fixing seat (i.e., in the axial direction). Therefore, it is very troublesome to assemble the latch piece in the radial through slot and the axial pivot hole respectively, which is time-consuming and labor-intensive, and brings trouble and inconvenience to the overall assembly. In particular, the pivot of the latch piece is relatively located at the middle position of the upper and lower sides of the latch piece, and the latch shoulder and spring of the control unit are respectively against the side surfaces of the two opposite ends of the latch piece to make the latch piece swing around the pivot, so the latch piece has a larger volume, which relatively greatly increases the overall volume of the screwdriver drive structure. In addition, since the control unit's actuating shoulder and spring respectively abut against the side surfaces of the two opposite ends of the latching piece to control the driving direction thereof, the reliability of the control over the driving direction thereof is relatively poor. Summary of the invention

[0004] In view of this, the present invention provides a screwdriver driving mechanism that can improve the above disadvantages to meet the above requirements.

[0005] A screwdriver drive mechanism comprises a base, a selection drive mechanism accommodated in the base, and a selection drive member sleeved on the rotation drive mechanism. The base comprises a accommodating tube, and two inlay accommodating cavities symmetrically arranged on the side walls of the accommodating tube of the accommodating tube. The contour line of the accommodating tube on a cross section perpendicular to the central axis of the accommodating tube comprises a first arc segment, two straight line segments separated on both sides of the first arc segment, U-shaped frame segments separated on both sides of the two straight line segments, and a second arc segment connected between the two U-shaped frame segments. The two straight line segments and the two U-shaped frame segments are symmetrically arranged with respect to each other in a plane passing through the central axis of the accommodating tube and form the inlay accommodating cavity accordingly. The two straight line segments are arranged tangent to the first arc segment. The selection drive mechanism comprises a central axis inserted in the accommodating tube, two meshing blocks respectively accommodated in the inlay accommodating cavities, and two restoring elastic members respectively squeezed by the meshing blocks and accommodated in the inlay accommodating cavity. The central shaft includes a circle of teeth arranged on the outer circumferential surface. The meshing block includes an abutting surface abutting the surface formed by the straight line segment, and a tooth surface meshing with the teeth of the central shaft and provided with teeth. When the restoring elastic member is compressed to the minimum length, the tooth surface disengages from the tooth portion. The selection drive member includes a mounting portion, an arc-shaped drive portion arranged on one side of the mounting portion, and at least one connecting block arranged on the other side of the mounting portion. The arc-shaped drive portion is inserted between the accommodating tube and the central shaft and is located between the two meshing blocks, and when the arc-shaped drive portion rotates, the meshing blocks are driven to disengage from the tooth portion respectively.

[0006] Furthermore, the insert accommodating cavity takes a plane passing through a central axis of the accommodating tube as a symmetry plane.

[0007] Furthermore, the accommodating tube and the accommodating cavity are formed by stretching and cutting the contour line of the accommodating tube along the direction of the central axis of the accommodating tube.

[0008] Furthermore, the diameter of the central axis is equivalent to the diameter of the second arc segment.

[0009] Furthermore, when one of the engagement blocks is engaged with the tooth portion and the other engagement block is disengaged from the tooth portion, the central axis can rotate in a direction away from the abutting direction of the restoring elastic member corresponding to the engagement block engaged with the tooth portion.

[0010] Furthermore, the screwdriver drive mechanism also includes a rotating selection sleeve that drives the selection drive member to rotate, and the rotating selection sleeve includes a sleeve sleeved on the outside of the accommodating tube, a step hole arranged at one end of the sleeve, and at least one clamping groove arranged on the step of the step hole and used to clamp the connecting block. When the rotating selection sleeve is sleeved on the base, the clamping groove is coupled with the clamping block and drives the selection drive member to rotate when the rotating selection sleeve rotates.

[0011] Furthermore, the mounting portion is sandwiched between the rotation selection sleeve and the end surface of the accommodating tube.

[0012] Furthermore, the rotation selection sleeve also includes a retaining spring for axially fixedly connecting with the base, and a retaining spring groove for accommodating the retaining spring.

[0013] Furthermore, the rotary selection sleeve also includes a positioning indicating mechanism, which includes a blind hole arranged on the base, a ball arranged in the blind hole, a counter spring sandwiched between the blind hole and the ball, and three indicating grooves arranged at intervals on the inner side wall of the rotary selection sleeve. When the rotary selection sleeve is sleeved on the base, the ball is counteracted by one of the three indicating grooves.

[0014] Compared with the prior art, the screwdriver drive mechanism provided by the present invention has two symmetrically arranged insert block accommodating cavities on the base, and the contour line of the insert block accommodating cavity on the cross section perpendicular to the central axis of the accommodating tube has a straight line segment and a U-shaped frame segment. Since the straight line segment is tangent to the first arc segment, the selection drive member can drive the engagement block slider when rotating, thereby disengaging from the tooth portion of the central axis. At the same time, due to the existence of the U-shaped frame segment, and there are only two of them, the volume of the U-shaped frame segment and the insert block accommodating cavity can be designed to be very large, that is, the volume of the engagement block, such as the thickness, can be increased, thereby improving the reliability of the screwdriver drive mechanism in the strength direction. Moreover, since there are only two engagement blocks, it can meet the forward and reverse rotation while also improving the control reliability, thereby ensuring the reliability of the screwdriver drive mechanism in all aspects. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The present invention provides a schematic diagram of the exploded structure of a screwdriver driving mechanism.

[0016] Figure 2 for Figure 1 A schematic diagram of the main structure of a base of a screwdriver driving mechanism.

[0017] Figure 3 for Figure 1 A schematic structural diagram of an engagement block of a selective drive mechanism of a screwdriver drive mechanism.

[0018] Figure 4 for Figure 1 The cross-sectional structure of the sleeve of the rotation selection sleeve of the screwdriver driving mechanism is shown in FIG.

[0019] Figure 5 for Figure 1 A schematic structural diagram of a cross section of a screwdriver drive mechanism.

[0020] Figure 6 for Figure 1 A schematic structural diagram of another cross section of a screwdriver drive mechanism. DETAILED DESCRIPTION

[0021] The specific embodiments of the present invention are further described in detail below. It should be understood that the description of the embodiments of the present invention herein is not intended to limit the protection scope of the present invention.

[0022] like Figure 1 and Figure 6 As shown, it is a structural schematic diagram of a screwdriver drive mechanism provided by the present invention. The screwdriver drive mechanism includes a base 10, a selection drive mechanism 20 accommodated in the base 10, a selection drive member 30 sleeved on the selection drive mechanism, and a rotating selection sleeve 40 driving the selection drive member 30 to rotate. It can be imagined that the screwdriver drive mechanism also includes some other functional structures, such as a screwdriver insertion hole provided in the selection drive mechanism 20, a connection structure provided on the base 10 for fixed connection with accessories such as a handle, etc., which are well-known technologies for those skilled in the art and will not be described in detail one by one here.

[0023] One end of the base 10 is used to connect with accessories such as a handle, and the other end is used to set the above-mentioned selection drive mechanism 20, the selection drive member 30, and the rotation selection sleeve 40, etc. Therefore, the base 10 includes a accommodating tube 11 and two insert accommodating chambers 12 symmetrically arranged on the side walls of the accommodating tube 11. The structural shapes of the accommodating tube 11 and the insert accommodating chamber 12 determine the reliability of the driving mechanism of this embodiment. Therefore, in order to fully explain the structural shapes of the accommodating tube 11 and the insert accommodating chamber 12, the contour line on the cross section perpendicular to the central axis of the accommodating tube 11 is used for explanation. On the cross section perpendicular to the central axis of the accommodating tube 11, the contour line of the accommodating tube 11 includes a first arc segment 13, two straight line segments 14 separated on both sides of the first arc segment 13, U-shaped frame line segments 15 layered on both sides of the two straight line segments 14, and a second arc segment 16 connected between the two U-shaped frame line segments 15. The diameter of the first arc segment 13 is greater than the diameter of the second arc segment 16, and the first and second arc segments 13, 16 are arranged concentrically. The two straight segments 14 are tangent to the first arc segment 13 respectively, so that the force applied by the selection drive member 30 to the meshing block described below can make it slide along the straight segment 14. One end of the U-shaped frame segment 15 is connected to the straight segment 14 and is used to accommodate the meshing block described below, and the cross-sectional shape of the meshing block can also be the same as the shape of the U-shaped frame segment 15. In terms of structural form, the two straight segments 14 and the two U-shaped frame segments 15 are symmetrically arranged with respect to the plane passing through the central axis of the accommodating tube 11 and form the insert accommodating chamber 12 accordingly, so that the two insert accommodating chambers 12 also take the plane passing through the central axis of the accommodating tube 11 as the symmetry plane. The contour line of the U-shaped frame line segment 15 is parallel to the plane passing through the central axis of the accommodating tube 11, so as to make full use of the side wall thickness of the accommodating tube 11, so that the thickness of the meshing block can be designed to be the thickest. It should be noted here that since the diameter of the screwdriver handle itself is standardized and the diameter of the drive head is also standardized, the side wall thickness of the accommodating tube 11 is limited, so that the side wall thickness of the accommodating tube 11 can be fully utilized to maximize the thickness of the meshing block, so as to increase the reliability of the strength of the meshing block. The second arc segment 16 is connected between the two U-shaped frame line segments 15, so as to be arranged opposite to the first arc segment 13. It can be understood that when the contour line of the accommodating tube 11 is determined, the structural shape of the accommodating tube 11 and the insert accommodating chamber 12 is also determined. Specifically, the accommodating tube 11 and the insert accommodating chamber 12 are formed by stretching and cutting the contour line of the accommodating tube 11 along the direction of the central axis of the accommodating tube 11.

[0024] The selection drive mechanism 20 includes a central shaft 21 inserted in the accommodating tube 11, two engaging blocks 22 respectively accommodated in the insert accommodating chamber 12, and two restoring elastic members 23 respectively pressed by the engaging blocks 22 and accommodated in the insert accommodating chamber 12. The central shaft 21 can be in two sections, one of which is accommodated in the accommodating tube 11 and the other is fixed in the fixed section of the base 10 to fully fix the position of the central shaft 21. The diameter of the portion of the central shaft 21 accommodated in the accommodating tube 11 is equal to the diameter of the second arc segment 16, so that the central shaft 11 is spaced from the first arc segment 13 to accommodate part of the selection drive member 30. Specifically, the central shaft 21 includes a circle of toothed teeth 211 arranged on the outer circumferential surface. Therefore, the maximum diameter of the toothed teeth 211 is equivalent to the diameter of the second arc segment 16. The extending direction of the teeth on the toothed teeth 211 can be parallel to the axis of the central shaft 11. The engagement block 22 includes an abutting surface 221 abutting against the surface formed by the straight segment 14, and a tooth surface 222 meshing with the teeth of the central axis 21 and provided with teeth. The engagement block 22 is embedded in the insert accommodating cavity 12 and can move in the insert accommodating cavity 12 under the action of external force. The reciprocating direction of the engagement block 22 is parallel to the symmetry plane of the two insert accommodating cavities 12 passing through the central axis of the accommodating cylinder 11, which is determined by the structure of the insert accommodating cavity 12. The restoring elastic member 23 is sandwiched between the engagement block 22 and the insert accommodating cavity 12, and is used to abut the engagement block 22 so that it can abut against the straight segment 14 and the tooth portion 211. The restoring elastic member 23 can be a spring. The working principle of the selection drive mechanism 20 will be described in detail below.

[0025] The selection drive member 30 includes a mounting portion 31, an arcuate drive portion 32 disposed on one side of the mounting portion 31, and at least one connection block 33 disposed on the other side of the mounting portion 31. The mounting portion 31 is used to mount the selection drive member 30, specifically, its cover is disposed on the end surface of the accommodating tube 11, so as to be sandwiched between the rotation selection sleeve 40 and the end surface of the accommodating tube 11 to fix its position in the axial direction. The mounting portion 31 is accommodated in the rotation selection sleeve 40 to fix its position in the radial direction. The arcuate drive portion 32 is inserted between the accommodating tube 11 and the central axis 21 and is located between the two engagement blocks 22, specifically, the arcuate drive portion 32 is inserted between the first arc segment 13 and the central axis 21. The arc-shaped driving portion 32 is in contact with the engagement block 22, so that when the arc-shaped driving portion 32 rotates clockwise or counterclockwise, the engagement block 22 can be driven to move, so that the tooth surface 22 of the corresponding engagement block 22 is disengaged from the tooth portion 211. The connecting block 33 is arranged on the other side of the mounting portion 31 along the central axis direction of the accommodating cylinder 11, and is coupled with the rotation selection sleeve 40, so that when the rotation selection sleeve 40 rotates, it can drive the selection driving member 30 to rotate.

[0026] The rotating selection sleeve 40 includes a sleeve 41 sleeved on the outside of the accommodating tube 11, a step hole 42 arranged at one end of the sleeve 41, at least one clamping groove 43 arranged on the step of the step hole 42 and used to clamp the connecting block 32, a clamping spring 44 for axially fixedly connected to the base 10, a clamping spring groove 45 for accommodating the clamping spring 44, and a positioning indicating mechanism 46 arranged between the sleeve 41 and the base 10. The sleeve 41 is sleeved on the base 10 and fixed to the base 10 to fix the selection drive mechanism 20 and the selection drive member 30. The step hole 42 is used to penetrate the central shaft 11 to insert a screwdriver or a bit. The clamping groove 43 is arranged on the step of the step hole 42 and used to clamp the connecting block 32, that is, the mounting portion 31 is sandwiched between the step hole 42 and the end surface of the accommodating tube 11. Since the connection block 32 is clamped in the clamping groove 43, the selection drive member 30 can be driven to rotate when the rotating connection sleeve 40 rotates. The clamping spring 44 is used to fix the sleeve 41 and the base 10. Specifically, the clamping spring 44 is clamped in the clamping spring groove 45. It can be understood that the radial dimension of the clamping spring 44 is larger than the radial dimension of the clamping spring groove 45, so that the base 10 is clamped between the clamping spring 44 and the step hole 42, thereby fixing the relative position between the base 10 and the sleeve 41. The positioning indicator mechanism 46 includes a blind hole 461 provided on the base 10, a ball 462 provided in the blind hole 461, a resisting spring 463 clamped between the blind hole 461 and the ball 462, and three indicator grooves 464 provided at intervals on the inner side wall of the rotating selection sleeve 40. The blind hole 461 is provided on the outer side wall of the base 10. The abutting spring 463 and the ball 462 are partially accommodated in the blind hole 461, so that the ball 462 abuts against the indicating groove 464 under the abutting spring 463. There are three indicating grooves 464, which are used to indicate the three states of the selection drive mechanism 20, namely, the idling state, the forward state, and the reverse state.

[0027] During operation, when the ball 462 abuts against the left indicator groove 464, the sleeve 41 drives the arc-shaped driving portion 32 of the selection drive member 30 to drive the left engagement block 22 to be accommodated in the insert block accommodating cavity 12, and the left engagement block 22 is disengaged from the gear ring 11. At this time, the central shaft 11 can rotate clockwise but not counterclockwise. When the ball 462 abuts against the right indicator groove 464, the working state of the central shaft 11 is exactly opposite to that when the ball 462 abuts against the left indicator groove 464. When the ball 462 abuts against the middle indicator groove 464, the central shaft can neither rotate clockwise nor counterclockwise under the abutment of the two engagement blocks 22.

[0028] Compared with the prior art, the screwdriver drive mechanism provided by the present invention has two symmetrically arranged insert accommodating cavities 12 on the base 10. On the cross section perpendicular to the central axis of the accommodating tube 11, the contour line of the insert accommodating cavity 12 has a straight line segment 14 and a U-shaped frame segment 15. Since the straight line segment 14 is tangent to the first arc segment 13, the selection drive member 30 can drive the engaging block 22 slider when rotating, thereby disengaging from the tooth portion 211 of the central axis. At the same time, due to the existence of the U-shaped frame segment 15, and there are only two of them, the volume of the U-shaped frame segment 15 and the insert accommodating cavity 12 can be designed to be very large, that is, the volume such as the thickness of the engaging block 22 can be increased, thereby improving the reliability of the screwdriver drive mechanism in the strength direction. Moreover, since there are only two engaging blocks 22, the forward and reverse rotation can be satisfied while the control reliability can be improved, thereby ensuring the reliability of the screwdriver drive mechanism in all aspects.

[0029] The above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modification, equivalent substitution or improvement within the spirit of the present invention is included in the scope of the claims of the present invention.

Claims

1. A screwdriver driving mechanism, characterized in that: The cam is secured to a position 56° to the left of the base and secured to the rear of the drive means, the cam being secured to a position 56° to the left of the base and being capable of accommodating the cam in an axial direction of the drive means. The locking member is configured to lock the locking cam of the locking cam and to lock the locking cam of the locking cam, wherein the locking cam is secured to the locking cam of the locking cam and is in a position to engage with the locking cam of the locking cam.

2. The screwdriver drive mechanism according to claim 1, wherein: The insert accommodating cavity takes the plane passing through the central axis of the accommodating cylinder as a symmetry plane.

3. The screwdriver drive mechanism according to claim 2, wherein: The reciprocating motion direction of the engaging block is parallel to the symmetry plane of the two insert accommodating cavities passing through the central axis of the accommodating cylinder.

4. The screwdriver drive mechanism according to claim 1, wherein: When one of the engagement blocks is engaged with the tooth portion and the other engagement block is disengaged from the tooth portion, the central shaft can rotate in a direction away from the abutting direction of the restoring elastic member corresponding to the engagement block engaged with the tooth portion.

5. The screwdriver driving mechanism according to claim 1, wherein: The screwdriver drive mechanism also includes a rotating selection sleeve that drives the selection drive member to rotate. The rotating selection sleeve includes a sleeve that is sleeved on the outside of the accommodating tube, a step hole provided at one end of the sleeve, and at least one clamping groove provided on the step of the step hole and used to clamp the connecting block. When the rotating selection sleeve is sleeved on the base, the clamping groove is coupled with the clamping block and drives the selection drive member to rotate when the rotating selection sleeve rotates.

6. The screwdriver driving mechanism according to claim 5, wherein: The mounting portion is sandwiched between the rotation selection sleeve and the end surface of the accommodating cylinder.

7. The screwdriver driving mechanism according to claim 5, wherein: The rotation selection sleeve further includes a clamping spring for axially fixedly connecting with the base, and a clamping spring groove for accommodating the clamping spring.

8. The screwdriver driving mechanism according to claim 5, wherein: The rotary selection sleeve also includes a positioning indicator mechanism, which includes a blind hole provided on the base, a ball provided in the blind hole, a counter-acting spring sandwiched between the blind hole and the ball, and three indicator grooves provided at intervals on the inner side wall of the rotary selection sleeve. When the rotary selection sleeve is sleeved on the base, the ball contacts one of the three indicator grooves.

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