Connector for coupling attachment on an electric tool

Description

FIELD OF INVENTION

[0001] This invention relates to power tools and particularly, although not exclusively, to power screw guns with a connector for coupling an attachment or a magazine to the body of the screw gun.BACKGROUND OF INVENTION

[0002] Conventional manual screw guns that work with one single screw at a time are quickly being replaced with automatic power screw guns that drive a series of fasteners from a collated strip. Such automatic power screw guns typically have a screw gun body, with an attachment to provide a collated strip of fasteners. The attachment is usually mated with the screw gun body through a connector fixedly attached to one end of the screw gun body, and where the connecting interfaces of the screw gun body and the attachment have corresponding structures for connection.

[0003] One problem with the existing connectors is that one needs to use some tools in order to dismount or mount the attachment from or to the screw gun body manually. This is very inefficient and time consuming. In some cases where the tools are lacked, the user may not be able to carry out his work, since he cannot mount or dismount the attachment to the screw gun bod

[0004] Another problem is that such mounting and dismounting require the user to move his or her hands from their normal operating positions to a carry out such operations. Even in cases where a latch is used for the mounting and dismounting of attachment, the user would still need to move one hand to the connector, and the other hand to pull the attachment out from the screw gun body. Prior art relating to the technical background of this invention can be seen in: EP 2 789 426 which discloses a power tool portion according to the preamble of claim 1, US 5,101,697; US 2012 / 074658; US 2013 / 093149; US 7,293,944 and US 2010 / 252292.SUMMARY OF INVENTION

[0005] It is therefore desirable to solve the abovementioned problems to enable a more efficient and convenient way to mount and dismount attachments to and from the screw gun body.

[0006] In the light of the foregoing background, it is an object to address the above needs, to overcome or substantially ameliorate the above disadvantages or, more generally, to provide a power tool with a connector for connecting an attachment to a screw gun body.

[0007] The above object is met by the combination of features of the independent claim; the dependent claims disclose further advantageous embodiments of the invention.

[0008] One skilled in the art will derive from the following description other objects of the invention. Therefore, the foregoing statements of object are not exhaustive and serve merely to illustrate some of the many objects of the present invention.

[0009] The present invention is a power tool portion, which comprises a rotatable collar and a locking member arranged to be actuated by the rotatable collar, wherein the rotatable collar is rotatable about an axis for actuating the locking member to removably engage the locking member with a second locking member of a second power tool portion, thereby releasably locking the power tool portion with the second power tool portion along the axis, wherein the power tool portion further comprises: a groove on an inner surface of the rotatable collar, a stop member movable parallel to the axis between an extended position and a retracted position and a biasing member biasing the stop member to the extended position wherein at the extended position, the stop member is engaged with the groove of the rotatable collar such that rotation of the locking member is obstructed and wherein at the retracted position, the stop member is not engaged with the groove of the rotatable collar such that rotation of the first locking member is unobstructed.

[0010] Preferably, the stop member is arranged to move from the extended position to the retracted position by an axial projection of the second locking member as the power tool portion is moved along the axis to couple with the second power tool portion.

[0011] Additionally, the power tool portion further comprises a torsion spring connected with the rotatable collar such that upon the stop member is being moved from the extended position to the retracted position, the rotatable collar is being rotated under a force of the torsion spring.

[0012] Preferably, the stop member extends at least partly into the locking member at the extended position.

[0013] Preferably, the locking member is arranged around the second locking member when the power tool portion locks with the second power tool portion.

[0014] Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.

[0015] The present invention therefore provides various configurations of an attachment connector for a screw gun. By utilising a rotatable connector, the present invention provides a more efficient and convenient way to mount and dismount attachments to and from the screw gun body.BRIEF DESCRIPTION OF FIGURES

[0016] The foregoing and further features of the present invention will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1A shows a perspective view of a portion of a power tool with a first power tool portion attached to a second power tool portion through a rotatable collar according to a first embodiment of the invention; Figure 1B shows a perspective view of the portion of the power tool in Figure 1A with the first power tool portion detached from the second power tool portion; Figure 2 shows a cross-sectional view of the portion of the power tool in Figure 1A and an exploded view of its corresponding components; Figure 3A shows a magnified perspective view of the connection between the first and second power tool portions in Figure 1A with the rotatable collar removed, where detachment is prevented; Figure 3B shows a magnified perspective view of the connection between the first and second power tool portions in Figure 1A with the rotatable collar removed, where detachment is allowed; Figure 3C shows a magnified perspective view of the rotatable collar in Figure 1A with some components removed; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Figures 1A and 1B show a perspective view of a portion of a power tool 100 with a first power tool portion 104 attached to and detached from a second power tool portion 102 respectively through a rotatable collar 106 along axis A. The connection end of the first power tool portion 104 has a corresponding structure for coupling with the connection end of the second power tool portion 102. The power tool 100 is a screw gun that requires an attachment to be coupled to the tool body. For illustration to aid understanding, the second power tool portion 102 is the tool body having a motor and connectable to batteries, and the first power tool portion 104 is an attachment for attaching to the tool body such that the tool is usable with strip of collated fasteners or screws.

[0018] Referring now to Figure 2, there is shown a cross-sectional view of the portion of the power tool 100 and an exploded view of its corresponding components. The first power tool portion 104 includes the rotatable collar 106 and a first locking member 108 which can be actuated by the rotatable collar 106. The second power tool portion 102 includes a second locking member 110. The first locking member 108 and the second locking member 110 are generally annular and have substantially the same diameter of which is smaller the inner diameter of the rotatable collar 106. The rotatable collar 106 is rotatable about axis A (shown in Figures 1A and 1B) by a user for actuating the first locking member 108 in a rotational manner for removably engaging the first locking member 108 with the second locking member 110, and thereby releasably locking the first power tool portion 104 with the second power tool portion 102 along the axis.

[0019] The first power tool portion 104 further comprises a stop member 114 movably parallel to the axis A between an extended position and a retracted position, where at the extended position, the stop member 114 extends partly into the first locking member 108. The stop member 114 is slightly elongated. Moreover, a biasing member 116 is also provided to bias the stop member 114 to the extended position. In this embodiment, the biasing member 116 is a spring, with one end fixedly attached to one end of the stop member 114. The first power portion 104 further has a torsion spring 118, which is annular in shape. In this embodiment, the torsion spring 118 is connected with the rotatable collar 106 such that during attachment when the stop member 114 is being moved from the extended position to the retracted position, the rotatable collar 106 can be rotated under a force of the torsion spring 118. The second locking member 110 of the second power tool portion 102 comprises an axial projection 112 for moving the stop member 114 from the extended position to the retracted position during attachment as the first power tool portion 104 moves along axis A to couple with the second power tool portion 102.

[0020] Referring to Figures 3A and 3B, which show a magnified perspective view of the connection between the first power tool portion 104 and the second power tool portion 102 with the rotatable collar 106 removed, where detachment is prevented and where detachment is allowed respectively. Note that under normal circumstance, the rotatable collar 106 is not arranged to be removed, and Figures 3A and 3B are shown with the rotatable collar 106 removed for illustration purpose only. Accordingly, when the first power tool portion 104 is locked with the second power tool portion 102, the first locking member 108 is arranged around the second locking member 110. The first locking member 108 is in contact with the inner surface of the rotatable collar 106 and the rotatable collar 106 is rotatable about axis A for rotating the first locking member 108 relative to the second locking member 110. The first locking member 108 and the rotatable collar 106 are connected for synchronous rotation.

[0021] Figure 3C shows a magnified perspective view of the rotatable collar 106 of the power tool 100. The rotatable collar 106 comprises a groove 126 on the inner surface. The groove 126 is elongated along the axial direction and has a radial width along the inner circumference of the collar 126 wide enough to fit in the stop member 114.

[0022] Now turning to the operation of the coupling mechanism, to remove the attachment from the screw gun body, the user simply needs to rotate the rotatable collar 106 in one direction, the stop member 114 would then be mated with the groove 126 and being urged to the extended position by the spring 116. At the extended position, the stop member 114 engages with the groove 126 of the rotatable collar 106 such that rotation of the first locking member 108 is obstructed. The limiting structures 122 and 124 of the first and second locking member 108 and 110 respectively are not engage or couple with each other, as shown in Figure 3B.

[0023] To install the attachment to the screw gun body, the user needs to insert the axial projection 112 into the groove 126 of the rotatable collar 106 from the other side such that the stop member 114 would be urged backward in the groove 126. At the retracted position, the stop member 114 is not engaged with the groove 126 of the rotatable collar 106 and the first locking member 108 rotates under the force of the torsion spring 118 relative to the second locking member 110. The sides where the first and second locking member 108 and 110 touches each other include a slant surface as shown in Figure 3B for restricting the degree of rotation with respect to each other, and as such forming a bayonet coupling between the two locking members 108, 110.

[0024] Although not shown in the figures, but in other embodiments, the power tool 100 may be another type of tools or devices that requires an attachment to be coupled to the tool body. In some embodiments, the power tool can be a drill, hammer drill, or an impact driver. In the examples illustrated, the second power tool portion is the tool body, and the first power tool portion is an attachment arranged to attach to the tool body. However, the first power tool portion can be the tool body, and the second power tool portion can be the attachment to be attached to the tool body. Similarly, the rotatable collar can be on the second power tool portion, instead of the first power tool portion. The quantities of components in the above embodiments are merely example, and can be more or less according to design needs.

[0025] Terms such as "forward", "rearward", "in front of", "behind", "highest", "lowest", "left", "right" and similar terms as used herein are for the purpose of describing the invention in its normal in-use orientation and are not intended to limit the invention to any particular orientation.

[0026] Any reference to prior art contained herein is not to be taken as an admission that the information is common general knowledge, unless otherwise indicated.

Claims

1. A power tool portion (104), comprising: a rotatable collar (106) and a locking member (108) arranged to be actuated by the rotatable collar; wherein the rotatable collar is rotatable about an axis (A) for actuating the locking member to removably engage the locking member with a second locking member (110) of a second power tool portion (102) when present, thereby releasably locking the power tool portion with the second power tool portion along the axis; wherein the power tool portion further comprises: a groove (126) on an inner surface of the rotatable collar; a stop member (114) movable parallel to the axis between an extended position and a retracted position; and a biasing member (116) biasing the stop member to the extended position; characterised in that at the extended position, the stop member is engaged with the groove of the rotatable collar such that rotation of the locking member is obstructed; and wherein at the retracted position, the stop member is not engaged with the groove of the rotatable collar such that rotation of the locking member is unobstructed.

2. The power tool portion of claim 1, wherein the stop member is arranged to move from the extended position to the retracted position by an axial projection (112) of the second locking member as the power tool portion is moved along the axis to couple with the second power tool portion.

3. The power tool portion of any one of claims 1 to 2, further comprises a torsion spring (118) connected with the rotatable collar such that upon the stop member being moved from the extended position to the retracted position, the rotatable collar is being rotated under a force of the torsion spring.

4. The power tool portion of any one of claims 1 to 3, wherein the stop member extends at least partly into the locking member at the extended position, and / or wherein the locking member is arranged around the second locking member when the power tool portion locks with the second power tool portion.

5. A power tool (100), comprising: a first power tool portion (104) according to any of claims 1 to 4, the locking member being a first locking member (108); and a second power tool portion (102) having a second locking member (110).