Mandrel assembly for use with rotary tool

Abstract

A spindle assembly (4) may be used with a rotary power tool (1) to provide a reliable and stable connection between the rotary tool (1) and a tool attachment (2). The spindle assembly (4) provides a quick connection / quick release connection between the tool output shaft (8) and the accessory (2) via a clamping action. In particular, the spindle assembly (4) is movable between a first configuration and a second configuration. In a first configuration, the accessory (2) may be clamped between a clamping element (56) formed at one end of the mandrel (50) and a collar (10) surrounding the mandrel (50). In the second configuration, the accessory (2) can be loaded onto the mandrel assembly (4) or detached from the mandrel assembly (4).

Description

BACKGROUND

[0001] Handheld rotary tools typically include a tool housing designed to be easily held in a human hand. The housing contains an electric motor operable to drive a rotatable chuck of the rotary tool. A mandrel is releasably coupled to the chuck so as to be rotatably driven by the rotary tool. In turn, an accessory is releasably secured to the mandrel, thereby enabling the rotary tool to rotatably drive the accessory. The accessory can be a cutting blade, a cutting wheel, a polishing wheel, a grinding wheel, a sanding disc, or any other similar device.

[0002] Many types of mechanisms can be used to secure an accessory to a mandrel. In one example, the mandrel includes a base having a threaded hole and a clamping screw that engages the hole so as to clamp the accessory between the base and the clamping screw. In this example, a tool is required to tighten the clamping screw. In another example, the accessory is connected to the mandrel via a quick connect clamp that is operated via a lever provided on the tool for this purpose. In this example, the lever mechanism adds weight, complexity, and cost to the tool. In both examples, with the accessory clamped as such, rotation of the rotary tool to the mandrel causes rotation of the accessory, thereby allowing the user to perform work on a workpiece.

[0003] Accordingly, it would be advantageous to provide a mandrel that can be quickly and easily used without requiring the use of an extra tool, such as a screwdriver, or the use of a relatively small, separate component, such as a clamping screw. Furthermore, it would be advantageous to provide a mandrel having a simple and easy to operate mechanism. SUMMARY

[0004] A mandrel assembly is disclosed that can be used with a rotary power tool to provide a reliable and stable connection between the rotary tool and a tool accessory. The mandrel assembly provides a quick connect / quick release connection between the tool output shaft and the accessory via a clamping action.

[0005] The mandrel assembly includes a mandrel in the form of a rigid rod, a collar having a hole that receives the mandrel therethrough, and a spring disposed in the hole and around the mandrel. The mandrel assembly is configured such that the spring biases the collar toward one end of the mandrel. The mandrel assembly is operable to clamp an accessory between a clamping element formed on the one end of the mandrel and the collar around a portion of the mandrel.

[0006] The mandrel assembly can be manually switched between a first, retracted configuration and a second, extended configuration. In the retracted configuration, the clamping element engages with the collar, and the attachment is secured relative to the collar by clamping force and engagement between the collar and the attachment. In the extended configuration, the clamping element is spaced apart from the collar, and the attachment can be mounted on or removed from the collar. The switching of the mandrel assembly between the first and second configurations is achieved by the relative movement of the collar and the mandrel in a predetermined motion. The predetermined motion is defined by the shape of a groove, also referred to as a "guide track," which is formed in the mandrel and engaged by a pin projecting radially inward from the inner surface of the collar. A groove is provided on each of the opposite sides of the mandrel. The groove is engaged by a pin projecting from the inner surface of the collar toward the mandrel. The groove is arranged along a curved path that rotates 90 degrees while the guide mandrel moves longitudinally relative to the collar.

[0007] The slot is configured such that the biasing force of the spring holds the clamping element in either a retracted or extended configuration. For this purpose, the slot provides two locking positions. A first locking position corresponds to the retracted configuration, where the pin is positioned in a first spindle position, and a second locking position corresponds to the extended configuration, where the pin is positioned in a fourth spindle position.

[0008] The first locking position corresponds to the end of the slot, while the second locking position corresponds to the stepped portion of the slot. When the pin is positioned in either the first or second locking position, the relative position of the mandrel and collar is maintained without manual force applied by the user. This is comparable to some conventional connection assemblies, in which it is necessary to hold the collar while inserting and rotating the accessory itself to install it. This combination of movements can be difficult in conventional connection assemblies because they may include a spring that pushes the collar against the shaft head. To change between the retracted and extended configurations, the user moves the collar or accessory only axially relative to the mandrel.

[0009] In some aspects, the mandrel assembly includes a mandrel, a collar, a retaining washer, and a spring. The mandrel includes a first end having a mandrel clamping element, a second end opposite the first end, a longitudinal axis extending through the first and second ends, and a groove provided in an outer surface of the mandrel. The collar surrounds the mandrel and includes a first end, a second end opposite the first end, and a sidewall extending between the first and second ends. The sidewall includes an inner surface defining a bore that opens at the first and second ends of the collar. The bore has a stepped diameter variation defining an inner shoulder of the collar. The collar includes a pin projecting from the surface of the bore and received in the groove. The retaining washer is secured to the mandrel and located between the groove and the second end of the mandrel. Furthermore, the spring surrounds the mandrel and extends between the retaining washer and the inner shoulder of the collar. When the collar moves relative to the mandrel in a first direction, the groove is configured to allow the mandrel to move relative to the collar in such a way that it both rotates about the longitudinal axis through a first angle and translates in a second direction, which is opposite to the first direction. When the collar moves relative to the mandrel in a second direction, the groove is configured to allow the mandrel to move relative to the collar in such a way that it both rotates about the longitudinal axis through a second angle and translates in the first direction, which is opposite to the first angle.

[0010] In some embodiments, at a first position of the slot, the slot is configured such that the biasing force of the spring holds the mandrel clamping element at a first distance from the collar. At a second position of the slot, the slot is configured such that the biasing force of the spring holds the mandrel clamping element at a second distance from the collar. The second distance is greater than the first distance.

[0011] In some embodiments, when the collar moves relative to the mandrel in a first direction, the groove is configured to allow the mandrel to translate linearly in a second direction, then rotate through a first angle, and then translate linearly again in the second direction.

[0012] In some embodiments, the first angle is 90 degrees.

[0013] In some embodiments, the second angle is 90 degrees.

[0014] In some embodiments, the first direction and the second direction are parallel to the longitudinal axis.

[0015] In some embodiments, the groove is configured such that when the mandrel rotates through one of the first and second angles, the mandrel also translates in a direction parallel to the longitudinal axis.

[0016] In some embodiments, the groove includes a first groove portion extending linearly and in a direction parallel to a longitudinal axis, and a second groove portion adjacent to the first groove portion, the second groove portion extending in a direction parallel to the longitudinal axis and extending circumferentially along a curved path. Furthermore, the groove includes a third groove portion adjacent to the second groove portion, the third groove portion extending linearly and circumferentially, and a fourth groove portion adjacent to the third groove portion extending linearly and axially.

[0017] In some embodiments, the second and third groove portions are combined to provide a path that causes the mandrel to rotate 90 degrees about the longitudinal axis when the pin travels along the path.

[0018] In some embodiments, the movement of the pin in the first groove portion corresponds to the movement of the mandrel relative to the collar, with its central shaft clamping element translating along a first direction; the movement of the pin in the second groove portion corresponds to the movement of the mandrel relative to the collar, with its central shaft clamping element translating along the first direction and the mandrel rotating about a longitudinal axis; the movement of the pin in the third groove portion corresponds to the movement of the mandrel relative to the collar, with its central shaft rotating about a longitudinal axis; and the movement of the pin in the fourth groove portion corresponds to the movement of the mandrel relative to the collar, with its central shaft clamping element translating along the first direction.

[0019] In some embodiments, the first groove portion begins outside the first end of the mandrel, the second groove portion, the third groove portion and the fourth groove portion are disposed between the first end of the mandrel and the mandrel shoulder, and the mandrel shoulder is disposed between the first end of the mandrel and the point centrally located between the first end of the mandrel and the second end of the mandrel.

[0020] In some embodiments, the collar includes a post projecting from a first end of the collar in a direction parallel to the longitudinal axis, and the collar includes a platform surface disposed between each adjacent pair of posts. When relative movement occurs between the collar and the mandrel in a direction parallel to the longitudinal axis, the slot is configured to allow the mandrel relative to the collar to move from a first configuration where the mandrel clamping element is aligned with and abuts the platform surface, to a second configuration where the mandrel clamping element is aligned with and spaced apart from the posts.

[0021] In some embodiments, the slot includes a first spindle position corresponding to a first locking position in which the biasing force of the spring holds the clamping element in a retracted configuration relative to the collar; and a second spindle position corresponding to a second locking position in which the biasing force of the spring holds the clamping element in a retracted configuration relative to the collar.

[0022] In some embodiments, the position of the first mandrel corresponds to one end of the groove.

[0023] In some embodiments, the second mandrel is positioned between and spaced apart from each end of the groove.

[0024] In some embodiments, the first locking position corresponds to the end of the slot, and the second locking position corresponds to the stepped portion of the slot. Attached Figure Description

[0025] Figure 1 This is a perspective view of the mandrel assembly that is connected to the chuck of the rotary tool.

[0026] Figure 2 yes Figure 1 A perspective view of the spindle assembly.

[0027] Figure 3 yes Figure 1 The spindle assembly along Figure 2 The cross-sectional view seen in line 3-3.

[0028] Figure 4 yes Figure 1 An exploded view of the spindle assembly and accessories.

[0029] Figure 5 This is a perspective view of the mandrel.

[0030] Figure 6 It is a magnified perspective view of the central axis that illustrates the details of the groove.

[0031] Figure 7 This is a side view of the magnified portion of the mandrel, illustrating the position of the mandrel represented by solid circles.

[0032] Figure 8 This is a top perspective view of the collar.

[0033] Figure 9 This is a top view of the collar.

[0034] Figure 10 It is the collar along Figure 9 The cross-sectional view seen in line 10-10.

[0035] Figure 11 This is a perspective view of the pin.

[0036] Figure 12 yes Figure 1 A perspective view of a portion of the mandrel assembly, illustrating the pin in the first groove portion and at the first mandrel position, whereby the mandrel clamping element is aligned with and abuts the collar platform surface.

[0037] Figure 13 yes Figure 1 A perspective view of a portion of the mandrel assembly, illustrating the pin in the first groove portion and at the second mandrel position, and illustrating the mandrel clamping element aligned with and spaced apart from the collar platform surface.

[0038] Figure 14 yes Figure 1 A perspective view of a portion of the mandrel assembly, illustrating the pin in the second groove portion and between the second and third mandrel positions, and illustrating that the mandrel clamping element is misaligned with the collar post and axially spaced from the collar post.

[0039] Figure 15 yes Figure 1 A perspective view of a portion of the mandrel assembly, illustrating the pin in the third groove and at the fourth mandrel position, and illustrating the mandrel clamping element aligned with and axially spaced from the collar post.

[0040] Figure 16 yes Figure 1 A perspective view of a portion of the mandrel assembly, illustrating the pin in the fourth groove and at the fifth mandrel position, and illustrating the mandrel clamping element aligned with the collar post and at the maximum axial distance from the collar post. Detailed Implementation

[0041] refer to Figure 1 and Figure 4 The spindle assembly 4 can be used to electrically rotate the tool 1 to provide a reliable and stable connection between the tool 1 and the tool attachment 2. The rotating tool 1 includes an electric motor 5. The output shaft 8 of the motor 5 terminates in a chuck 6 configured to be coupled to the spindle 50 of the spindle assembly 4. The tool attachment 2, such as a cutting wheel 200, is configured to be releasably connected to the spindle assembly 4 via a quick-release clamping action, as discussed in detail below. Operating the rotating tool 1 rotates the chuck 6, which in turn rotates the spindle assembly 4, thereby transmitting rotational motion to the cutting wheel 200.

[0042] refer to Figures 2-4 The spindle assembly 4 includes a spindle 50, a collar 10 having a hole 21 through which the spindle 50 passes, and a helical spring 90 surrounding the spindle 50 and disposed in the hole 21. The helical spring 90 is held in the hole 21 by a retaining washer 80. The spindle assembly 4 also includes a flat washer 85 disposed between the retaining washer 80 and one end 92 of the helical spring 90. The components of the spindle assembly 4 will now be described in detail.

[0043] refer to Figures 4-7 The mandrel 50 is a rigid, elongated, and generally rod-shaped structure having a first end 51 and a second end 52 opposite to the first end 51. The mandrel 50 includes a longitudinal axis 53 extending through the first and second ends 51, 52 and corresponding to the axis of rotation of the mandrel assembly 4. As used herein, the term "axially" refers to the longitudinal axis 53 or a direction parallel to the longitudinal axis 53, and the term "radially" refers to a direction along a radius perpendicular to and intersecting the longitudinal axis 53.

[0044] The mandrel 50 is cylindrical with a stepped diameter, such that the first end 51 of the mandrel has a larger diameter than the second end 52. The mandrel 50 includes a shoulder 59 at the transition between the large-diameter portion 54 and the small-diameter portion 55. The shoulder 59 is located between the first end 51 and a point 60, which is located midway between the first and second ends 51 and 52.

[0045] The mandrel 50 includes a shallow annular groove 69 extending circumferentially. In the illustrated embodiment, the groove 69 is located in the small-diameter portion 55 adjacent to the mandrel shoulder 59.

[0046] The first end 51 of the mandrel defines a rigid mandrel clamping element 56. The mandrel clamping element 56 is a plate extending in a plane perpendicular to the longitudinal axis 53. The plate has an irregular profile defining a central circular hub 57 and a pair of arms 58 projecting from opposite sides of the hub 57. Each arm 58 has a circular sector shape, thus giving the mandrel clamping element 56 a bow-tie appearance when viewed in a direction parallel to the longitudinal axis 53. The hub 57 is centered on the longitudinal axis 53, and the arms 58 are positioned on opposite sides of the hub 57 and aligned along a first axis A1 perpendicular to and intersecting the longitudinal axis 53. With this configuration, the mandrel 50 has a T-shape when viewed in a side view.

[0047] The second end 52 of the mandrel is configured to be received in the chuck 6 of the rotary tool 1. In the illustrated embodiment, the second end 52 of the mandrel is rounded to facilitate insertion into the chuck 6.

[0048] A pair of grooves 100 are provided on the surface of the large-diameter portion 54 of the mandrel for placement between the first end 51 of the mandrel and the shoulder 59 of the mandrel. The grooves 100 are identical and located on opposite sides of the mandrel 50. Each groove 100 is equidistant from each of the first end 51 and the shoulder 59 of the mandrel. The grooves 100 form a path configured for travel by the respective pins 30 of the collar 10, as described below. For this purpose, each groove 100 is sized to receive the pin 30 and allow translation therein. The grooves 100 have an irregular shape designed to guide the pin 30 along a predetermined path that causes both translation and rotation of the mandrel 50 relative to the collar 10 and the longitudinal axis 53. Details of the grooves 100 and the interaction between the pins 30 and the grooves 100 are described below.

[0049] refer to Figure 3 and Figures 8-10The collar 10 is a hollow rigid cylinder surrounding a portion of a mandrel 50. The collar 10 includes a sidewall 19 extending between a first end 11 and a second end 12 opposite to the first end 11. An inner surface 20 of the sidewall 19 defines a hole 21. The hole 21 is centered on a longitudinal axis 53 and has a diameter larger than the diameter of the large-diameter portion 54 of the mandrel, thereby creating an annular gap 23 between the mandrel 50 and the inner surface 20 of the sidewall. The gap 23 is sized to receive a helical spring 90 positioned around the mandrel 50, as discussed below.

[0050] The first end 11 of the collar is closed by an end wall 18, except for a centrally located opening 16 from which the mandrel 50 protrudes. The opening 16 is sized to allow the mandrel 50 to rotate and translate freely relative to the collar 10. The outer surface of the end wall 18 defines a first end surface 18 (1) perpendicular to the longitudinal axis 53. The end wall 18 includes a pair of diametrically opposed end wall through openings 18 (2) extending in a direction perpendicular to the longitudinal axis 53 and communicating with the hole 21.

[0051] refer to Figures 8-11 The collar 10 includes a pair of pins 30. In the illustrated embodiment, the pins are identical and each pin 30 has an inner end 31, an outer end 32, and an intermediate portion 33 disposed between the inner end and the outer ends 31, 32. Each pin 30 has a non-uniform diameter, such that the outer end 32 has a larger diameter than the intermediate portion 33, and the intermediate portion 33 has a larger diameter than the inner end 31. The intermediate portion 33 of each pin 30 is press-fitted into a corresponding end-wall through opening 18 (2), and the inner end 31 protrudes into an opening 16. The pins 30 are disposed on opposite sides of the openings 16 and aligned along a second axis A2 perpendicular to and intersecting the longitudinal axis 53. The shape and size of the inner end 31 of each pin 30 are configured to be received in a corresponding groove 100 disposed in the large-diameter portion 54 of the mandrel in a sliding fit manner, as discussed in detail below. The outer end 32 of each pin 30 has a diameter greater than that of the corresponding end wall through opening 18 (2), thus the outer end 32 is located outside the collar 10 and limits the depth to which the pin 30 can be inserted into its respective end wall through opening 18 (2).

[0052] A pair of posts 14 project axially outward from a first end surface 18(1). The posts 14 are positioned on opposite sides of the opening 16 to be aligned along a third axis A3 that is parallel to and intersects the longitudinal axis 53. The third axis A3 is parallel to and axially aligned with a second axis A2 that extends through the pin 30. With this configuration, each pin 30 is axially aligned with the corresponding post 14. Each post 14 has an arc shape when viewed in a direction parallel to the longitudinal axis 53. The portion of the first end surface 18(1) positioned between the posts 14 is referred to as a platform surface 15. The platform surface 15 has the same shape and size as the posts 14 and is axially recessed relative to the respective end surface 14(1) of the posts 14. Similar to the posts 14, the platform surface 15 is positioned on opposite sides of the opening 16 to be aligned along a fourth axis A4 that is perpendicular to and intersects the longitudinal axis 53, wherein the fourth axis A4 is perpendicular to the third axis A3.

[0053] The inner surface of the end wall 18 defines an inner shoulder 22 of the collar extending between the inner surface 20 of the side wall and the central opening 16. The inner shoulder 22 of the collar faces the second end 12 of the collar and serves as a seat for the first end 91 of the helical spring 90.

[0054] The second end 12 of the collar includes an enlarged flange 24 that projects radially outward and extends around the circumference of the sidewall 19. The enlarged flange 24 provides a gripping surface that facilitates manual gripping of the collar 10 and pushing the collar 10 to translate axially relative to the spindle 50, as discussed further below.

[0055] refer to Figures 3-5 The mandrel 50 is held within the collar 10 by a retaining washer 80, which surrounds the small-diameter portion 55 of the mandrel immediately adjacent to the shoulder 59. In the illustrated embodiment, the outer periphery of the retaining washer 80 is a flat ring 81 having an outer diameter smaller than the diameter of the hole 21 and an inner diameter smaller than the diameter of the small-diameter portion 55 of the mandrel. The inner periphery 82 of the retaining washer 80 includes circumferentially spaced teeth 83. The teeth 83 are angled such that the innermost edges of the teeth 83 are non-coplanar with respect to the ring 81. As a result, the teeth 83 engage the outer surface of the small-diameter portion 55 of the mandrel to secure the retaining washer 80 relative to the mandrel 50. In the illustrated embodiment, the teeth 83 engage with a groove 69 of the mandrel 50, thereby fixing the axial position of the retaining washer 80. The retaining washer 80 is positioned relative to the mandrel 50 such that the ring 81 is radially aligned with the shoulder 59 of the mandrel.

[0056] In addition to the retaining washer 80, the mandrel assembly 4 includes a flat washer 85 having an inner diameter larger than the diameter of the large-diameter portion 54 of the mandrel and an outer diameter received in a clearance fit within a hole 21. The flat washer 85 is disposed on the large-diameter portion 54 of the mandrel to abut against the retaining washer ring 81. Furthermore, the flat washer 85 is disposed in the hole 21 between the retaining washer 80 and the inner shoulder 22 of the collar.

[0057] The mandrel assembly 4 includes a helical spring 90 disposed in a gap 23 between the collar 10 and the mandrel 50. The helical spring 90 is coaxial with and surrounds the mandrel 50. A first end 91 of the helical spring 90 abuts against the inner shoulder 22 of the collar, and an opposite second end 92 of the helical spring 90 abuts against a flat washer 85, which in turn abuts against a retaining washer 80. The helical spring 90 is sized to be in a compressed state in the mandrel assembly 4, such that the helical spring 90 biases the collar 10 toward the first end 51 of the mandrel.

[0058] In some embodiments, the spindle assembly 4 may include a hollow cylindrical spacer (not shown) positioned adjacent to the retaining washer 80 on the side of the retaining washer 80 opposite to the flat washer 85, surrounding the small-diameter portion 55 of the spindle. The spacer serves to limit the depth to which the spindle 50 is inserted into the chuck 6 of the rotary tool 1. Specifically, when the user inserts the second end 52 of the spindle into the chuck 6, a physical interaction occurs between the chuck 6 and the spacer, thereby preventing the user from further pushing the spindle assembly 4 into the chuck 6. When the spindle assembly 4 is clamped into the chuck 6, the spacer ensures sufficient space between the chuck 6 and the open second end 12 of the collar 10. This sufficient space between the two components ensures that the collar 10 has sufficient space for axial travel to allow attachment 2 to be attached to and removed from the spindle assembly 4.

[0059] Refer again Figure 4 The spindle assembly 4 is operable to quickly and easily attach the attachment 2 to the rotary tool 1. The attachment 2, such as the cutting wheel 200, is secured to the first end 51 of the spindle via the clamping action of the spindle assembly 4. The cutting wheel 200 includes a rigid hub 204 and a rigid disc portion 202 surrounding the hub 204. The disc portion 202 defines the outer periphery of the attachment 2, which in this embodiment provides a cutting surface. A centrally located hub opening 206 is formed in the hub 204.

[0060] In the illustrated embodiment, the hub opening 206 defines a circular central cutout 208, a first cutout 209 disposed on one side of the central cutout 208, and a second cutout 210 disposed on the side of the central cutout 208 opposite to the first cutout 209. The first cutout 209 and the second cutout 210 each have a circular sector shape, thus giving the hub opening 206 a bow-tie appearance when viewed in top view of Annex 2. The cutouts 208, 209, and 210 are aligned along a fifth axis A5. The central cutout 208 has a diameter that accommodates the hub 57 of the first end 51 of the mandrel in a tolerance fit, and the shapes and dimensions of the first cutout 209 and the second cutout 210 are configured to receive the collar post 14 passing through them in a tolerance fit. With this configuration, as discussed below, when the accessory 2 is connected to the spindle assembly 4, a portion 204(1) of the hub 204 adjacent to the center cutout 208 is axially aligned with and close to the platform surface 15 of the collar 10.

[0061] In some embodiments, the cutting wheel 200 is formed by molding the disc portion 202 with a material combination comprising an abrasive material, a resin material, and one or more glass fiber mesh segments. This molding process is well known in the field of manufacturing cutting wheels.

[0062] refer to Figures 3-4 and Figures 5-7 The mandrel 50 includes grooves 100 each providing a guide track configured to guide pins 30 of collar 10 along a predetermined path, resulting in movement of the mandrel 50 relative to collar 10. In particular, the grooves 100 guide the pins 30 such that collar 10 both translates along and rotates about the longitudinal axis 53 of the mandrel 50.

[0063] Each slot 100 is sized to receive the pin 30 with a clearance fit. Each slot 100 is located in the large-diameter portion 54 of the mandrel and defines a curved path. The term "curved" refers to a path that has both curved and linear portions.

[0064] The grooves 100 are identical, therefore only one groove 100 will be described in detail. In the illustrated embodiment, the groove 100 includes four groove portions 101, 102, 103, and 104. The groove portions 101, 102, 103, and 104 extend between five predetermined positions 61, 62, 63, 64, and 65 of the mandrel 50. The mandrel positions 61, 62, 63, 64, and 65 are located at... Figure 7 The center is represented by a solid circle.

[0065] The first groove portion 101 extends between a first mandrel position 61 and a second mandrel position 62. The first mandrel position 61 is located in a first plane P1 perpendicular to the longitudinal axis 53, and the second mandrel position 62 is located in a second plane P2 perpendicular to the longitudinal axis 53. The first plane P1 is located at or adjacent to the first end 51 of the mandrel. The second plane P2 is axially spaced from the first plane P1 and located between the first plane P1 and the mandrel shoulder 59. The second mandrel position 62 is axially aligned with the first mandrel position 61, thereby making the first groove portion 101 linear and axially extending.

[0066] The second groove portion 102 extends between the second mandrel position 62 and the third mandrel position 63. The third mandrel position 63 is located in a third plane P3 perpendicular to the longitudinal axis 53. The third plane P3 is axially spaced from the first plane P1 and the second plane P2, and is disposed between the second plane P2 and the mandrel shoulder 59. Furthermore, when viewed towards the first end 11 of the collar, the third mandrel position 63 is spaced from the second mandrel position 62 along the circumference of the collar 10. For example, in some embodiments, the arc length of the space between the second mandrel position 62 and the third mandrel position 63 (e.g., the arc length of the second groove portion 102) is 85 degrees. In other words, the third mandrel position 63 is offset by 85 degrees relative to the second mandrel position 62 along the circumference of the mandrel 50. The second groove portion 102 extends slightly curvedly and extends both axially and circumferentially.

[0067] The third groove portion 103 extends between a third spindle position 63 and a fourth spindle position 64. The fourth spindle position 64 is located in a third plane P3. The fourth spindle position 64 is offset relative to the third spindle position 63 along the circumference of the spindle 50. The offset along the circumference of the spindle relative to the third spindle position 63 is five degrees, which corresponds to an offset within a 90-degree range relative to the second position 62 (for example, the third spindle position 63 is located between the second spindle position 62 and the fourth spindle position 64 in the circumferential direction of the spindle 50). With this configuration, the third groove portion 103 extends linearly and circumferentially.

[0068] The fourth groove portion 104 extends between the fourth mandrel position 64 and the fifth mandrel position 65. The fifth mandrel position 65 is located in a fourth plane P4 perpendicular to the longitudinal axis 53. The fourth plane P4 is axially spaced from the first plane P1, the second plane P2, and the third plane P3. The fourth plane P4 is disposed between the third plane P3 and the mandrel shoulder 59, thereby the fifth mandrel position 65 is closer to the mandrel shoulder 59 than the first mandrel position 61 to the fourth mandrel position 64. The fifth mandrel position 65 is axially aligned with the fourth mandrel position 64, thereby the fourth groove portion 104 is linear and extends axially.

[0069] In groove 100, the first groove portion 101 and the fourth groove portion 104 are parallel to each other and offset circumferentially along the mandrel 50. Furthermore, the length of the first groove portion 101 (e.g., the axial distance between the first mandrel position 61 and the second mandrel position 62) is greater than the length of the fourth groove portion 104 (e.g., the axial distance between the fourth mandrel position 64 and the fifth mandrel position 65). For example, in the illustrated embodiment, the length of the fourth groove portion 104 is approximately forty percent of the length of the first groove portion 101.

[0070] The third groove portion 103 has a size that roughly corresponds to the diameter of the inner end 31 of the pin, and is relatively shorter than the first groove portion 101 and the fourth groove portion 104. The third groove portion 103 intersects the fourth groove portion 104 at a right angle, thereby giving the groove a stepped appearance at this location.

[0071] refer to Figure 7 and Figures 12-15 The spindle assembly 4 can be in a first, retracted configuration ( Figure 12 ) and second, extension configuration ( Figure 16 The mandrel assembly 4 is manually switched between the first and second configurations. The mandrel assembly 4 is switched from a first configuration to a second configuration by relative movement between the mandrel 50 and the collar 10, guided by the movement of the pin 30 within a groove from a first mandrel position 61 to a fifth mandrel position 65. During the switch between the first and second configurations, the groove 100 guides the pin 30 along a predetermined path, causing the mandrel 50 to both translate and rotate relative to the collar 10. The switch of the mandrel assembly 4 from the first configuration to the second configuration will now be described.

[0072] Initially, the spindle assembly 4 can be in the first, retracted configuration ( Figure 12 In the first configuration, pin 30 is positioned in the first spindle position 61 of the first slot portion 101. When pin 30 is positioned in the first spindle position 61, spindle clamping element 56 is positioned at the first end 11 of the collar. Furthermore, the first axis A1 is aligned with the fourth axis A4, thereby aligning the arm 58 of the spindle clamping element 56 with the platform surface 15. The first spindle position 61 is positioned such that when no tool accessory 2 is mounted on the spindle assembly 4 (as shown), the collar platform surface 15 is pushed against the arm 58 by the coil spring 90. Furthermore, the spindle 50 is prevented from rotating relative to the collar 10 because the arms 58 of the spindle clamping element 56 are positioned between their respective posts 14, and each arm 58 is fan-shaped and sized to correspond to the shape and size of the platform surface 15.

[0073] In the first configuration, the pin 30 pushes against the circumferentially extending opposing surface 101(1) of the first groove portion 101 and is held in this position by the axial force of the coil spring 90. Therefore, the opposing surface 101(1) of the first groove portion 101 serves as a stop for the movement of the pin 30, and the first spindle position 61 corresponds to the first locked position of the spindle assembly 4.

[0074] refer to Figure 13 The user can initiate the transition between the first and second configurations by manually moving the collar 10 toward the second end 52 of the spindle against the axial force of the helical spring 90. As a result, the pin 30 moves axially along the first groove portion 110 from the first spindle position 61 to the second spindle position 62. During the movement between the first spindle position 61 and the second spindle position 62, the spindle 50 moves axially relative to the collar 10 without rotating, causing the spindle clamping element 56 to move away from the platform surface 15, while the first axis A1 and the fourth axis A4 remain axially aligned.

[0075] refer to Figure 14 While continuing to move the collar 10 against the axial force of the helical spring 90 toward the second end of the spindle, the pin 30 moves from the second spindle position 62 to the third spindle position 63 via the second groove portion 102. During the movement between the second spindle position 62 and the third spindle position 63, the spindle 50 continues to move axially relative to the collar 10, causing the spindle clamping element 56 to move further away from the post 14. Furthermore, the circumferential movement of the pin 30 causes the spindle 50 to rotate relative to the collar 10. As previously described, the second groove portion 102 allows for approximately 85 degrees of relative rotation. Figure 14 The pin 30 is located at the center position between the second mandrel position 62 and the third mandrel position 63.

[0076] refer to Figure 15 When pin 30 moves from third spindle position 63 to fourth spindle position 64 along third groove portion 103 against the axial force of helical spring 90, spindle 50 moves circumferentially relative to collar 10 without axial translation. The rotation is approximately five degrees, such that the total circumferential rotation allowed by second groove portion 102 and third groove portion 103 is 90 degrees. When pin 30 is in fourth spindle position 64, spindle clamping element 56 has been rotated to be axially aligned with post 14. That is, first axis A1 is aligned with third axis A3, while the arm 58 of clamping element 56 is slightly axially spaced from the end face 14(1) of each post 14.

[0077] refer to Figure 16When pin 30 moves from fourth spindle position 64 to fifth spindle position 65 against the axial force of helical spring 90, spindle 50 moves axially along fourth groove portion 104 until pin 30 stops in fifth spindle position 65. When pin 30 is in fifth spindle position 65, first axis A1 is aligned with third axis A3, such that arm 58 of spindle clamping element 56 is aligned with post 14 and maximally spaced from end face 14(1) of each post.

[0078] The arrangement in which the first axis A1 is aligned with the third axis A3 and the arm 58 of the clamping element 56 is axially spaced from the end face 14 (1) of each column 14 corresponds to the second, extended configuration of the spindle assembly 4. It should be noted that the second configuration is achieved when the pin 30 is disposed in the third groove portion 103 or the fourth groove portion 104, including the case where the pin 30 is in the fourth spindle position 64, the fifth spindle position 65, or any position between the fourth spindle position 64 and the fifth spindle position 65.

[0079] When pin 30 is in the fourth groove portion 104 and the user stops manually moving collar 10 toward the second end 52 of the spindle, the axial force of the coil spring 90 pushes collar 10 to move axially toward the first end 51 of the spindle. Because the third groove portion 103 extends in a purely circumferential direction, when pin 30 reaches the fourth pin position 64, pin 30 abuts against the opposing surface 103(1) of the third groove portion 103 and is held in this position by the axial force of the coil spring 90. Therefore, the opposing surface 103(1) of the third groove portion 103 serves as a stop for the axial movement of pin 30, and the fourth pin position 64 corresponds to the second locked position of the spindle assembly 4.

[0080] From Figure 12 The first configuration shown in the diagram is to Figure 16 In the transition of the second configuration shown, pin 30 has passed through the entire length of its respective slot 100. During the passage of pin 30 through slot 100, spindle clamping element 56 has been lifted off platform surface 15 and rotated 90 degrees about longitudinal axis 53.

[0081] In the extended configuration, attachment 2 can be mounted on or removed from collar 10 because the arm 58 of spindle clamping element 56 is aligned with and spaced apart from column 14. Because the arm 58 is aligned with and spaced apart from column 14, the fifth axis A5 is aligned with the first axis A1 by the orientation attachment, spindle clamping element 56 and column 14 can be inserted into (or removed from) the hub opening 206 of attachment 2, and attachment 2 can be mounted on (or removed from) the first end surface 18(1) of collar 10.

[0082] In order to install on collar 10 ( Figure 16Attachment 2 (not shown) is fixed to the first end 11 of the collar, allowing the spindle assembly 4 to move from the second configuration to the first configuration, while attachment 2 abuts against the first end surface 18 (1) of the collar.

[0083] The user can initiate the transition from the second configuration to the first configuration by manually moving the collar 10 circumferentially out of the fourth spindle position (e.g., out of the second locking position) and moving the collar into the second slot portion 102. After the pin 30 is released from the second locking position, the biasing force of the coil spring pushes the pin 30 toward the first end 51 of the spindle. During the movement from the fourth spindle position 64 to the first spindle position 61, the spindle 50 rotates in the opposite direction to the rotation direction that occurs when transitioning from the first configuration to the second configuration. For example, if the spindle 50 rotates counterclockwise when viewed facing the first end 51 when transitioning from the first configuration to the second configuration, then the spindle 50 rotates clockwise during the transition from the second configuration to the first configuration.

[0084] When the attachment 2 is mounted on the first end surface 18(1) of the collar and the spindle assembly 4 is in the first configuration, the attachment 2 is prevented from rotating relative to the collar 10 via the engagement between the hub opening 206 of the attachment 2 and the post 14 of the collar 10. Furthermore, since the portion 204(1) of the hub 204 adjacent to the center cutout 208 is axially aligned with and abuts against the platform surface 15 of the collar 10, the hub portion 204(1) is clamped between the arm 58 of the spindle clamping element 56 and the platform surface 15 by the axial force of the coil spring 90.

[0085] In order to release the clamped Attachment 2, as described above relative to... Figures 12-16 The collar 10 is switched from a first configuration to a second configuration by moving the pin 30 along the groove 100 from the first spindle position 61 to the fifth spindle position 65.

[0086] The slot 100 is configured such that the biasing force of the coil spring 90 holds the clamping element 56 in either a retracted or extended configuration. For this purpose, the slot 100 provides each of the two locking positions discussed above. The first locking position corresponds to the retracted configuration, wherein the pin 30 is positioned in the first spindle position 61 and the arm 58 of the clamping element 56 abuts against the platform surface 15 of the collar 10. The second locking position corresponds to the extended configuration, wherein the pin 30 is positioned in the fourth spindle position 64, and the clamping element 56 is spaced apart from the platform surface 15 of the collar 10 and the arm 58 of the clamping element 56 is aligned with the post 14.

[0087] As described above, a spindle assembly 4 is disclosed, which allows attachment 2 to be quickly and easily attached to and / or detached from the spindle assembly 4 without the need for additional tools such as screwdrivers. Therefore, the spindle assembly 4 can be conveniently used to connect a variety of interchangeable attachments to the power tool 1, such as cutting wheels, polishing wheels, grinding wheels, grinding discs, or similar articles.

[0088] In the illustrated embodiment, both the mandrel 50 and the collar 10 are formed of metal (such as steel). However, depending on the requirements of the specific application, the mandrel 50 may be formed of a material different from that of the collar 10. In some embodiments, the mandrel 50 and the collar 10 may be formed of alternative materials (such as high-strength polymers determined according to application requirements).

[0089] In the illustrated embodiment, the collar 10 includes a pair of pins 30. The collar 10 is not limited to having two pins. For example, in some embodiments, the collar 10 includes a single pin 30. In other embodiments, the collar 10 includes multiple pairs of pins 30, such as four or more pins 30.

[0090] Selective illustrative embodiments of the spindle assembly for power tools have been described in considerable detail above. It should be understood that only structures deemed necessary for illustrating the spindle assembly have been described herein. Other conventional structures, as well as the structures of auxiliary and accessory components of the spindle assembly, power tool, and accessories, are assumed to be known and understood by those skilled in the art. Furthermore, while working examples of the spindle assembly have been described above, the spindle assembly is not limited to the working examples described above, but various design changes can be made without departing from the device set forth in the claims.

Claims

1. A mandrel assembly comprising: a mandrel, the mandrel comprising: a mandrel first end having a mandrel clamping element, a mandrel second end opposite the mandrel first end, a longitudinal axis extending through the mandrel first and second ends, and a groove disposed in a mandrel outer surface; a collar surrounding the mandrel, the collar comprising: a collar first end, a collar second end opposite the first end, and a sidewall extending between the collar first and second ends, the sidewall comprising an inner surface defining a bore, the bore opening at the collar first and second ends, the bore having a diameter step change defining a collar inner shoulder, and a pin protruding from a surface of the bore and received in the groove; a retaining washer secured to the mandrel between the groove and the mandrel second end; and a spring surrounding the mandrel, the spring extending between the retaining washer and the collar inner shoulder, wherein, when the collar is moved relative to the mandrel in a first direction, the groove is configured to allow the mandrel to move relative to the collar in two ways: both rotation about the longitudinal axis through a first angle and translation in a second direction, the second direction being opposite the first direction, and when the collar is moved relative to the mandrel in the second direction, the groove is configured to allow the mandrel to move relative to the collar in two ways: both rotation about the longitudinal axis through a second angle and translation in the first direction, the second angle being opposite the first angle.

2. The mandrel assembly of claim 1, wherein, at a first position of the groove, the groove is configured such that a biasing force of the spring maintains the mandrel clamping element at a first distance from the collar; at a second position of the groove, the groove is configured such that the biasing force of the spring maintains the mandrel clamping element at a second distance from the collar; and the second distance is greater than the first distance.

3. The mandrel assembly of claim 1, wherein, when the collar is moved relative to the mandrel in the first direction, the groove is configured to allow the mandrel to: linearly translate in the second direction, then rotate through the first angle, and then linearly translate in the second direction.

4. The mandrel assembly of claim 1, wherein, the first angle is 90 degrees.

5. The mandrel assembly of claim 1, wherein, the second angle is 90 degrees.

6. The mandrel assembly of claim 1, wherein, the first and second directions are parallel to the longitudinal axis.

7. The mandrel assembly of claim 1, wherein, the groove is configured such that when the mandrel is rotated through one of the first and second angles, the mandrel also translates in a direction parallel to the longitudinal axis.

8. The mandrel assembly of claim 1, wherein, the groove comprises: a first groove portion extending linearly and in a direction parallel to the longitudinal axis; a second groove portion adjoining the first groove portion, the second groove portion extending in the direction parallel to the longitudinal axis and circumferentially along a curved path; a third groove portion adjoining the second groove portion, the third groove portion extending linearly and circumferentially; and a fourth groove portion adjoining the third groove portion, the fourth groove portion extending linearly and axially.

9. The mandrel assembly of claim 8, wherein, the second and third groove portions combine to provide a path that, when the pin travels in the path, causes the mandrel to rotate 90 degrees about the longitudinal axis.

10. The spindle assembly of claim 8, wherein, movement of the pin in the first slot portion corresponds to movement of the spindle relative to the collar in which the spindle clamp element translates in the first direction; movement of the pin in the second slot portion corresponds to movement of the spindle relative to the collar in which the spindle clamp element translates in the first direction and the spindle rotates about the longitudinal axis; movement of the pin in the third slot portion corresponds to movement of the spindle relative to the collar in which the spindle rotates about the longitudinal axis; and movement of the pin in the fourth slot portion corresponds to movement of the spindle relative to the collar in which the spindle clamp element translates in the first direction.

11. The spindle assembly of claim 8, wherein, the first slot portion begins at the first end of the spindle; the second slot portion, the third slot portion, and the fourth slot portion are disposed between the first end of the spindle and the shoulder of the spindle; and the shoulder of the spindle is disposed between the first end of the spindle and a point of the spindle that is midway between the first end of the spindle and the second end of the spindle.

12. The spindle assembly of claim 1, wherein, the collar includes a post projecting from the first end of the collar in a direction parallel to the longitudinal axis; the collar includes a platform surface disposed between each adjacent pair of posts; upon relative movement between the collar and the spindle in a direction parallel to the longitudinal axis, the slot is configured to allow the spindle to move relative to the collar: from a first configuration in which the spindle clamp element is aligned with and abuts the platform surface, to a second configuration in which the spindle clamp element is aligned with and spaced apart from the pair of posts.

13. The mandrel assembly of claim 1, wherein, the slot includes: a first spindle position corresponding to a first locked position in which the biasing force of the spring maintains the clamp element in a retracted configuration relative to the collar; and a second spindle position corresponding to a second locked position in which the biasing force of the spring maintains the clamp element in a retracted configuration relative to the collar.

14. The mandrel assembly of claim 13, wherein, the first spindle position corresponds to one end of the slot.

15. The mandrel position of claim 13 wherein, the second spindle position is disposed at a position between and spaced apart from each end of the slot.

16. The spindle assembly of claim 13, wherein, the first locked position corresponds to an end of the slot, and the second locked position corresponds to a stepped portion of the slot.

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