A locking drill chuck

Abstract

This invention provides a locking drill chuck with a self-locking structure including a ring of teeth and a spring piece. A cantilever spring segment is provided, synchronized with the spring piece in the rotation direction of the nut. The cantilever spring segment has a positioning protrusion. The inner wall of the rotating sleeve has a first groove and a second groove that mate with the positioning protrusion. An extension section is provided after the positioning protrusion of the cantilever spring segment, including a guide support surface. Before the positioning protrusion disengages from the first groove, the portion of the cantilever spring segment after the positioning protrusion contacts the drill chuck structure located radially inward of that portion, with the inner surface of the guide support surface contacting and abutting against it without the end abutting against it. This invention improves the anti-inertia self-loosening unlocking performance of locking drill chucks with anti-inertia self-loosening unlocking function, and also prevents the cantilever spring segment from abutting against the drill chuck structure radially inward, thus preventing the drill chuck with this anti-inertia self-loosening unlocking function from jamming and becoming unable to rotate due to spring piece fatigue and drooping.

Description

Technical Field

[0001] This utility model relates to a drill chuck, and more particularly to a hand-tightening drill chuck with a locking function. Background Technology

[0002] A hand-operated drill chuck consists of a drill body, jaws, a nut, and a rotating sleeve. The nut and jaws are threaded together, and the rotating sleeve and nut are connected directly or through a connecting structure. By manually operating the rotating sleeve, the nut is rotated, causing the jaws to move forward or backward, thus clamping or releasing the drill bit. Some drill chucks also have a locking mechanism, which typically includes a toothed ring fixed to the surface of the drill body and a spring plate connected to the nut. The spring plate is located radially outside the toothed ring and enters a locked state under the control of the rotating sleeve.

[0003] With the development of lithium battery technology, electric drills are rotating at increasingly faster speeds. When drilling, the drill experiences a sudden drop in speed and stops, generating inertia. This sudden stop can cause the drill chuck to loosen, manifesting as the rotating sleeve unlocking due to inertia. This causes the nut to rotate in the direction the drill chuck jaws open, leading to the drill bit coming loose. Even with locking mechanisms, current lithium battery technology may render the drill chuck's locking mechanism ineffective.

[0004] Currently, some locking drill chucks use a protrusion on the other end of the spring plate to circumferentially position the rotating sleeve in a locked state, but its positioning force needs to be improved and its ability to resist inertia needs further improvement. Utility Model Content

[0005] The purpose of this utility model is to provide a locking drill chuck that further improves the anti-inertia self-loosening unlocking performance of the locking drill chuck. To this end, this utility model adopts the following technical solution:

[0006] A locking drill chuck includes a rotating sleeve, a drill body, a nut, jaws, and a self-locking structure. The rotating sleeve is connected to the nut via a connecting structure, enabling the nut to rotate. The nut is fitted onto the drill body and supported by a step in the middle of the drill body. The self-locking structure includes a ring of teeth and a spring plate. The spring plate has a locking end and a control protrusion near the locking end. The locking drill chuck has a cantilever spring segment that rotates synchronously with the spring plate in the direction of nut rotation. The cantilever spring segment has a radially outward positioning protrusion. The inner wall of the rotating sleeve has a first groove and a second groove that mate with the positioning protrusion. When the locking drill chuck is in the self-locking state, the positioning protrusion is located at the first groove. In the groove, when the positioning protrusion is located in the second groove, the locking drill chuck is in the unlocked state. When unlocked, the positioning protrusion is pressed to dislodge from the first groove, allowing the nut to be rotated. The positioning protrusion is rotated towards the second groove. The feature is that the cantilever spring segment is provided with an extension segment after the positioning protrusion. The extension segment includes a guide support surface, such that before the positioning protrusion dislodges from the first groove, the portion of the cantilever spring segment after the positioning protrusion contacts the drill chuck structure located radially inward of that portion, and the inner surface of the guide support surface contacts and abuts against it without the end abutting.

[0007] Based on the above technical solutions, the present invention may also adopt the following further technical solutions, or combine these further technical solutions:

[0008] The drill chuck structure located radially inside this part is a drill chuck nut or a component fixed to the nut.

[0009] The component that is fixed to the nut includes a nut sleeve.

[0010] Of the guide support surface, at least a portion that is not at the end remains substantially parallel to the outer surface of the nut in its free state.

[0011] The locking drill chuck is equipped with a spring plate mounting structure, and a positioning key is provided on the spring plate mounting structure. The spring plate and the cantilever spring plate are respectively located on both sides of the positioning key. The positioning key cooperates with the keyway of the nut or the component fixed with the nut for circumferential positioning.

[0012] The locking structure includes a locking ring and a positioned internal gear ring. A positioning key is provided at the front of the locking ring. The spring piece and the cantilever spring piece are located on both sides of the positioning key. The positioning key engages with the keyway of a nut or a component fixed to the nut for circumferential positioning. The spring piece has an outwardly protruding locking end that engages with the internal ratchet on the internal gear ring. The rotating sleeve is provided with a structure to control the locking end. In the axial direction, the cantilever spring piece is located in front of the internal gear ring.

[0013] The internal gear ring includes a ring-shaped base, on which are provided internal gear pieces that can elastically deform radially outward to press against the rotating sleeve. The internal gear pieces are provided with internal ratchet teeth on their inner sides. The drill chuck is provided with a pressing hook between the nut and the step, so that the counter-thrust force during the rotation of the drill chuck causes the nut to move backward, and the internal gear ring to bend backward and radially outward, pushing and pressing the internal gear pieces to elastically deform and open radially outward, thus pressing them tightly against the inner wall of the rotating sleeve.

[0014] The ring-shaped base of the internal gear ring is placed on the step, and the ring-shaped base of the internal gear ring has a radially outer open portion, and the internal gear plate is bent and disposed on the outer edge of the open portion.

[0015] There is a ring-shaped bearing ball cavity between the internal gear ring and the nut. The bearing ball cavity is provided with bearing balls. The bearing ball cavity has a rearward and radially outward working surface. During operation, the bearing balls are squeezed radially outward and the internal gear plate is elastically deformed radially outward.

[0016] The locking ring includes a ring-shaped base, which is located between the ring-shaped base of the internal gear ring and the rear end of the nut; the ring-shaped base of the locking ring and the internal gear ring together form the ring-shaped bearing ball cavity, and the ring-shaped base of the locking ring is provided with the rearward and radially outward action surface.

[0017] The internal gear ring protrudes radially inward through the inner wall of its ring-shaped base to form a circumferential fit with the drill body to prevent relative rotation.

[0018] By employing the technical solution of this utility model, the present invention can improve the anti-inertia self-loosening unlocking performance of the locking drill chuck with anti-inertia self-loosening unlocking function by providing an extension section to support the positioning structure and strengthening the elasticity of the positioning protrusion. Furthermore, it can prevent the cantilever spring segment from pressing against the drill chuck structure on its radially inner side, thus preventing the drill chuck with this anti-inertia self-loosening unlocking function from becoming stuck and unable to rotate due to spring fatigue and drooping. Moreover, this structure of the present invention has better structural performance for self-locking structures using internal gear rings. Attached Figure Description

[0019] Figure 1 This is an exploded view of the drill chuck structure of Embodiment 1 of this utility model.

[0020] Figure 2 This is a cross-sectional view of the drill chuck of Embodiment 1 of this utility model.

[0021] Figure 3 This is a schematic diagram of the combination of the locking ring and the internal gear ring in Embodiment 1 of this utility model.

[0022] Figure 4 This is a cross-sectional view (AA) of Embodiment 1 of the present invention after entering the locked state.

[0023] Figure 5 This is a cross-sectional view (AA) of Embodiment 1 of the present invention before entering the locked state or after exiting the locked state.

[0024] Figure 6 This is the front view of Embodiment 1 of the present invention with the rotating sleeve hidden.

[0025] Figure 7 This is a cross-sectional view of a prior art drill chuck, showing a schematic diagram of the drill chuck slumping and jamming after the fatigue decay of the cantilever spring segment.

[0026] Figure 8 This is another embodiment of the present invention, a cross-sectional view AA after entering the locked state.

[0027] Figures 9-11 This is a bottom view schematic diagram of different implementation methods of the present invention with drive shaft connection.

[0028] Figure 12 This is a cross-sectional view of another embodiment of the present invention with drive shaft connection.

[0029] Figure 13 This is a cross-sectional view of one embodiment of the present invention that is connected to the drive shaft.

[0030] Figure 14 , 15 These are bottom-view schematic diagrams showing the locking and unlocking of another embodiment of the present invention connected to the drive shaft.

[0031] Figure 16 for Figure 14 , 15 A cross-sectional view of the drill chuck according to the embodiment shown.

[0032] Figure 17 This is a cross-sectional view of an embodiment of the present invention that uses a quick-change structure to lock the drive shaft.

[0033] Figure 18 for Figure 17 The illustrated embodiment is a schematic diagram of the drive connection hole and the drive shaft drive connection method. Detailed Implementation

[0034] See attached document Figures 1-8This utility model provides a locking drill chuck, including a rotating sleeve, a drill body 1, a nut 3, a jaw 2, and a self-locking structure. The nut 3 and the jaw 2 are threadedly connected. The rotating sleeve includes an outer sleeve 41 and a bushing 42 fixed together with the outer sleeve 41 and adapted to a specific configuration. The bushing 42 is connected to the nut 3 through a connecting structure, which can drive the nut 3 to rotate and drive the jaw 2 to move back and forth to clamp or release the drill bit. The nut 3 is outside the drill body and supported on a step 11 in the middle of the drill body.

[0035] The self-locking structure includes a ring of teeth and a spring piece 51. The spring piece 51 is provided with a locking end 52 and a control protrusion 53 near the locking end. The locking drill chuck is provided with a cantilever spring segment 54 that is synchronized with the spring piece in the rotation direction of the nut. The cantilever spring segment 54 is provided with a radially outward positioning protrusion 55. The inner wall of the rotating sleeve is provided with a first groove 421 and a second groove 422 that mate with the positioning protrusion 55. When the locking drill chuck is in the self-locking state, the positioning protrusion 55 is located in the first groove 421. When the positioning protrusion 55 is located in the second groove 422, the locking drill chuck is in the unlocked state. In the unlocking state, by pressing the positioning protrusion 55, the positioning protrusion 55 is dislodged from the first groove 421, allowing the nut 3 to be rotated. The positioning protrusion 55 is driven to rotate towards the second groove 422. The cantilever spring segment is provided with an extension section 56 after the positioning protrusion. The extension section 56 includes a guide support surface 561, such that before the positioning protrusion 55 dislodes from the first groove 421, the portion of the cantilever spring segment 54 after the positioning protrusion 55 contacts the drill chuck structure located radially inward of this portion, and the inner surface of the guide support surface contacts and abuts against it without the end abutting (see...). Figure 4 , 5 ).

[0036] Before the positioning protrusion 55 disengages from the first groove 421, the portion of the cantilever spring segment 54 behind the positioning protrusion 55 contacts the drill chuck structure located radially inward of that portion. This can be because when the positioning protrusion 55 is fully positioned in the first groove 421 and performing its positioning function, the portion behind the positioning protrusion 55 is already in contact with the drill chuck structure (e.g., Figure 4 (As shown), it can also be that when the positioning protrusion 55 is fully positioned in the first groove 421 and is not yet in contact with the drill chuck structure (as shown). Figure 8 As shown), but when it is driven to rotate and pressed to begin to disengage from the first groove, the portion after the positioning protrusion 55 contacts the drill chuck structure.

[0037] The drill chuck structure located radially inside this part is the drill chuck nut 3 or a component fixed to the nut (such as a nut sleeve).

[0038] Preferably, at least a portion of the guide support surface 561, not at the ends, remains substantially parallel to the outer surface of the nut 3 in its free state (e.g., ...). Figure 4 , Figure 8 (As shown).

[0039] The locking drill chuck is equipped with a spring plate mounting structure, and a positioning key 57 is provided on the spring plate mounting structure. The spring plate 51 and the cantilever spring plate 54 are respectively located on both sides of the positioning key 57. The positioning key 57 is circumferentially positioned by cooperating with the keyway of the nut or the component fixed with the nut.

[0040] In this embodiment, the locking structure adopts an internal tooth structure. The locking structure includes a locking ring 5 and a positioned internal tooth ring 6. The locking ring 5 serves as the spring piece mounting structure, and the positioning key 57 is provided at the front of the locking ring 5. The locking end 52 is tilted outward, and the movement direction of the locking end 52 during locking is opposite to the movement direction of the cantilever spring piece 54 against the support, which is beneficial for structural arrangement. The internal tooth ring 6 is provided with internal ratchet teeth 611 as the first ring of teeth. The bushing 42 is provided with a structure for controlling the locking end 52 (a cam surface can be used). Axially, the cantilever spring piece 54 is located in front of the internal tooth ring 6.

[0041] The locking ring 5 is connected to the nut 3 and rotates synchronously with the nut 3 around the central axis of the drill body 1. The internal gear ring 6 includes a ring-shaped base 60. The ring-shaped base 60 is provided with an internal gear plate 61 that can elastically deform radially outward and squeeze into the rotating sleeve. The internal gear plate 61 is provided with an internal ratchet 611 facing radially inward. The internal ratchet 611 cooperates with the locking end 52. By controlling the structure of the locking end and the cooperation of the control protrusion 53, the locking end 52 can be disengaged from or inserted into the internal ratchet 611. The drill chuck is provided with a squeezing hook between the nut 3 and the step 11. The counter-thrust causes the nut 3 to move backward, and the internal gear ring 6 bends backward and radially outward (obliquely backward and outward). It pushes and squeezes the internal gear plate 61 to elastically deform and open radially outward, and squeezes it tightly against the inner wall of the rotating sleeve and is constrained, which enhances the overall locking force of the drill chuck and prevents the nut 3 and the rotating sleeve 42 from loosening on their own.

[0042] The nut 3 can be provided with a rotation groove 31. The groove walls 32 on both sides of the rotation groove can cooperate with the key on the inner wall of the rotating sleeve (the bushing 42 in the rotating sleeve in this embodiment) to connect the rotating sleeve 42 and the nut 3 during the tightening process in the locked state and the loosening process after unlocking.

[0043] For the internal gear ring 6, an internal gear plate 61 is provided on its ring-shaped base 60, and a gap 62 is provided in the internal gear plate 61 so that the internal gear plate 61 is elastic and can undergo elastic deformation.

[0044] The ring-shaped base 60 of the internal gear ring 6 is placed on the step 11. The internal gear ring 6 is axially positioned by being pressed against the drill body 1 by the part in front of it. The ring-shaped base 60 of the internal gear ring 6 has a radially outer open portion 63. The internal gear plate 61 is bent and disposed on the outer edge of the open portion 63, which can reduce the diameter of the drill body 1 and increase the elastic deformation effect.

[0045] The locking ring 5 includes a ring-shaped base 50, which is located between the ring-shaped base 60 of the internal gear ring 6 and the rear end of the nut 3. The ring-shaped base 50 and the internal gear ring 6 together form a ring-shaped bearing ball cavity, in which bearing balls 7 are disposed. The ring-shaped base 50 has a rearward and radially outward working surface 501, which, during operation, squeezes the bearing balls 7 radially outward and causes the internal gear plate 61 to elastically deform radially outward.

[0046] The internal gear ring 6 is positioned so as not to rotate relative to the drill body 1. Multiple arc grooves are formed on the drill body 1 by axially drilling holes along its edges. The ring-shaped base 60 of the internal gear ring 6 is a sheet-like ring. During punching, arc protrusions 64 are formed around its inner hole to mate with the arc grooves, creating a circumferential fit that prevents relative rotation. This makes both manufacturing the grooves and manufacturing and installing the internal gear ring 6 very convenient.

[0047] The nut 3 is an integral nut, and the retaining ring 8 is used to axially limit the nut 3 in front, and the retaining ring 8 is engaged with the drill body.

[0048] Figure 7 This demonstrates a situation where the end 54b of the cantilever spring segment in the prior art fails to support the positioning protrusion 55b and droops due to fatigue, causing the drill chuck to jam.

[0049] The present invention utilizes the cantilever spring segment to support the positioning protrusion 55, thereby improving the anti-inertia self-loosening and unlocking performance of the locking drill chuck and preventing fatigue drooping and jamming of the drill chuck. It can also be applied to locking drill chucks with an external tooth structure (i.e., the ring of teeth that matches the locking end faces outward).

[0050] See attached document Figure 9 - 11 represents different implementation methods of this utility model for drive connection with the drive shaft. Figure 9 The drive mechanism uses a square hole 12a connected to a square shaft drive shaft. Figure 10 The drive mechanism uses a hexagonal hole 12b connected to a hexagonal prism drive shaft. Figure 11 It adopts a drive form that uses a flat hole 12c connected to a flat drive shaft. Figure 12 The drive shaft is connected using screw 13.

[0051] Figure 13The chuck 14 is axially positioned and driven to connect with the drive shaft. Reference numeral 9 is a rear sleeve 9 that can move axially. After the drive shaft is inserted into the drive connection hole at the rear end of the drill body, the rear sleeve is pulled axially. The chuck 14 can enter the connection hole and connect with the drive shaft under the drive of the cam arm 91 on the rear sleeve 9. It is held in place by the cam arm 91 and cannot move backward. When the rear sleeve 9 moves in the opposite direction, the cam arm 91 releases the lock on the chuck 14. When the drive shaft is pulled out, the chuck 9 can be squeezed and moved radially backward, allowing the drill chuck to pull out the drive shaft.

[0052] Figure 14 , 15 16 is a method of connecting the clamping plates to the drive shaft. A pair of spring-driven clamping plates 15 are mounted on the rear sleeve 9, and a switch 16 is provided. The drill body 1 has a slit hole for the clamping plates 15 to enter. When the button 16 is pressed, as... Figure 15 As shown, the clip is opened, allowing the drive shaft to be inserted or removed. The drive shaft has a groove that engages with the clip, with the bottom of the groove being flat. When the drive shaft is inserted, the button 16 is released, and the clip closes under the drive of the spring, passes through the slit hole, and is inserted into the groove, clamping the drive shaft and being axially limited on the drive shaft and connected to the drive.

[0053] like Figure 17 , 18 As shown, in this embodiment, a quick-change structure is used to lock the drive shaft. The drive connection hole 101 in the drill body 1b is connected to the drive shaft by a keyway fit 103. The quick-change structure includes a rear sleeve 9b that can rotate at a small angle. A reset torsion spring 104 is provided between the rear sleeve 9b and the drill body 1b. A hole 105 is provided in the wall of the drive connection hole of the drill body. A retaining ball 106 is provided in the hole 105. The rear sleeve 9b is driven to reset and rotate to the locked position by the reset torsion spring 104. The cam 102 provided on the inner side of the rear sleeve controls the retaining ball 106 to move forward and protrude into the drive connection hole 101 to lock the drive shaft. By manually rotating the rear sleeve 9b in the opposite direction, the cam deviates from the hole 105, and the retaining ball 106 can exit the drive connection hole 101 to unlock the drive shaft.

[0054] The above description is only a specific embodiment of the present utility model, but the structural features of the present utility model are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present utility model are covered by the protection scope of the present utility model.

[0055] It should be noted that the terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this utility model are intended to cover non-exclusive inclusion. The terms "installed," "set," "equipped with," "connected," "linked," and "sleeve" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0056] In the description of this utility model, it should be understood that the terms "one end," "the other end," "outer side," "inner side," "horizontal," "end," "length," "outer end," "left," and "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. The terms "first" and "second" are also used only for the sake of brevity in description and do not indicate or imply relative importance.

Claims

1. A locking drill chuck, comprising a rotating sleeve, a drill body, a nut, jaws, and a self-locking structure, wherein the rotating sleeve is connected to the nut via a connecting structure and can drive the nut to rotate, the nut being sleeved on the drill body and supported on a step in the middle of the drill body; the self-locking structure includes a ring of teeth and a spring piece, the spring piece having a locking end and a control protrusion near the locking end, the locking drill chuck having a cantilever spring segment synchronized with the spring piece in the rotation direction of the nut, the cantilever spring segment having a radially outward positioning protrusion, the inner wall of the rotating sleeve having a first groove and a second groove that mate with the positioning protrusion, when the locking drill chuck is in a self-locking state, the positioning protrusion is located in the first groove, and when the positioning protrusion is located in the second groove, the locking drill chuck is in an unlocked state, wherein during unlocking, by pressing the positioning protrusion, the positioning protrusion is dislodged from the first groove, thereby driving the nut to rotate, and the positioning protrusion is driven to rotate towards the second groove; characterized in that... The cantilever spring segment is provided with an extension section after the positioning protrusion. The extension section includes a guide support surface, such that before the positioning protrusion disengages from the first groove, the portion of the cantilever spring segment after the positioning protrusion contacts the drill chuck structure located radially inside that portion, and the inner surface of the guide support surface contacts and abuts against it without the end being pressed against it.

2. A locking drill chuck as described in claim 1, characterized in that, The drill chuck structure located radially inside this part is a drill chuck nut or a component fixed to the nut.

3. A locking drill chuck as described in claim 2, characterized in that, The component that is fixed to the nut includes a nut sleeve.

4. A locking drill chuck as described in claim 1, characterized in that, Of the guide support surface, at least a portion that is not at the end remains substantially parallel to the outer surface of the nut in its free state.

5. A locking drill chuck as described in claim 1, characterized in that, The locking drill chuck is equipped with a spring plate mounting structure, and a positioning key is provided on the spring plate mounting structure. The spring plate and the cantilever spring plate are respectively located on both sides of the positioning key. The positioning key cooperates with the keyway of the nut or the component fixed with the nut for circumferential positioning.

6. A locking drill chuck as described in claim 1, characterized in that, The locking drill chuck includes a locking ring and a positioning internal gear ring. A positioning key is provided at the front of the locking ring. The spring piece and the cantilever spring piece are located on both sides of the positioning key. The positioning key cooperates with the keyway of the nut or the component fixed to the nut for circumferential positioning. The spring piece has an outwardly protruding locking end that engages with the internal ratchet on the internal gear ring. The rotating sleeve is provided with a structure to control the locking end. In the axial direction, the cantilever spring piece is located in front of the internal gear ring.

7. A locking drill chuck as described in claim 6, characterized in that, The internal gear ring includes a ring-shaped base, on which are provided internal gear pieces that can elastically deform radially outward to press against the rotating sleeve. The internal gear pieces are provided with internal ratchet teeth on their inner sides. The drill chuck is provided with a pressing hook between the nut and the step, so that the counter-thrust force during the rotation of the drill chuck causes the nut to move backward, and the internal gear ring to bend backward and radially outward, pushing and pressing the internal gear pieces to elastically deform and open radially outward, thus pressing them tightly against the inner wall of the rotating sleeve.

8. A locking drill chuck as described in claim 7, characterized in that, The ring-shaped base of the internal gear ring is placed on the step, and the ring-shaped base of the internal gear ring has a radially outer open portion, and the internal gear plate is bent and disposed on the outer edge of the open portion.

9. A locking drill chuck as described in claim 7, characterized in that, There is a ring-shaped bearing ball cavity between the internal gear ring and the nut. The bearing ball cavity is provided with bearing balls. The bearing ball cavity has a rearward and radially outward working surface. During operation, the bearing balls are squeezed radially outward and the internal gear plate is elastically deformed radially outward.

10. A locking drill chuck as described in claim 9, characterized in that, The locking ring includes a ring-shaped base, which is located between the ring-shaped base of the internal gear ring and the rear end of the nut; the ring-shaped base of the locking ring and the internal gear ring together form the ring-shaped bearing ball cavity, and the ring-shaped base of the locking ring is provided with the rearward and radially outward action surface.

11. A locking drill chuck as described in claim 6, characterized in that, The internal gear ring protrudes radially inward through the inner wall of its ring-shaped base to form a circumferential fit with the drill body to prevent relative rotation.

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