GB2461576A

GB2461576A - Tool with collet chuck

Info

Publication number: GB2461576A
Application number: GB0812341A
Authority: GB
Inventors: Michael Brailey
Original assignee: SMC Corp Ltd
Current assignee: SMC Corp Ltd
Priority date: 2008-07-04
Filing date: 2008-07-04
Publication date: 2010-01-06
Also published as: GB0812341D0

Abstract

A tool 21 comprises a collet chuck 22 having open and closed states, suitable for gripping a target object in the closed state and releasing the target object in the open state, a control portion 23 manually actuable by a user to control the opening and closing of the chuck, and an elongate section 25 having first and second ends 25a, 25b, the chuck 22 and control portion 23 being mounted on the first end 25a. The first end 25a is preferably remote from the handle, which can be attached to the tool 21 using attachment portion 26 at the second end 25b. The control portion 23 preferably comprises a sleeve which can be moved along the elongate portion 25 to open and close the collet 22 by a barrel 27 which is rotated to move along a threaded rod 24. The elongate portion 25 may be flexible or rigid. In a further aspect, the tool 21 comprises a collet chuck 22 having open and closed states, suitable for gripping a target object in the closed state and releasing the target object in the open state, a control portion 23 manually actuable by a user to control the opening and closing of the chuck, and an attachment portion 26, (46, figure 4) connected to the chuck, adapted for detachable attachment to at least one of a handle and an extension portion (47, figure 4). The tool 21 may be a nut driver.

Description

Field of the Invention

The present invention relates to tools for turning objects such as screws, and particularly but not exclusively to nut drivers for tightening or loosening hose clips.

Background of the Invention

In a wide range of applications, it is necessary to apply a rotational force to a screw head or similar object, an illustrative example is when tightening or loosening a screw/band hose clamp. A known device suitable for applying a rotational force to a screw head is a nut driver, an example of which is the Nut Driver Pr0TM sold by SMC. This is shown schematically in Figure 1.

The nut driver 1 of Figure 1 includes a collet chuck, for gripping and turning hexagonal screw heads, a handle 4 for gripping by the user, and a lever 5 close to the handle 4 for closing and opening the chuck. The collet chuck includes a collet 2 with open and closed states. In the open state, a head of the collet 2 has at least two gaps 2b around its circumference to form two or more sections 2a. The sections 2a form a hexagonal opening 2c for receiving the screw head, with the hexagonal opening 2c being larger than the head of the screw. The collet chuck also has and a sleeve 3, which is coaxial with the collet 2 and surrounds at least a tail end of the collet, the tail end being opposite the head end. One end of the sleeve 3 contacts the lever 5, and the lever 5 is arranged to move the sleeve 3 towards or away from the collet 2.

When the sleeve 3 is moved towards the collet 2, the sections 2a of the collet 2 are moved towards each other, closing the gaps 2b between them and reducing the size of the hexagonal opening 2c to put the collet 2 into a closed state.

In use, the collet 2 is placed over the head of the screw while the collet 2 is in an open state. The collet 2 is then placed in a closed state by operating the lever 5, causing the collet 2 to grip the head of the screw. The collet 2 is maintained in the closed state while turning the screw. Thereafter, the lever 5 is used to put the collet 2 in the open state, thereby releasing the grip on the screw head and allowing the collet 2 to be easily disengaged from the screw head.

The known device described above allows a user to rotate a screw only if the handle 4 is positioned coaxially with the screw and rotated about the common axis. However, it is often necessary to use nut drivers in cramped conditions, and there may be cases in which there is an obstruction preventing positioning of the handle 4 in this way.

In order to allow torque about one axis to be converted into torque about another axis, a flexible extension is known. This is an elongate flexible device made of tightly wound wire with an attachment for the socket of a socket wrench at one end and an attachment for a handle at the other. The flexibility of the extension allows it to be bent, so that the axis of the handle may be different from the axis of the socket. Rotation of the handle is transmitted along the extension to the socket, even when the extension is bent, thereby allowing the socket to be rotated by handle, even when they are not coaxial. This type of flexible extension has been successfully applied to sockets. However, sockets do not grip the screw head, and so are likely to become detached from the screw head unintentionally. Therefore, it is desirable to provide a nut driver providing similar functionality to the flexible extension while maintaining the functionality of gripping the screw head.

In the known device shown in Figure 1, the sleeve 3 must extend from the collet 2 to the vicinity of the handle 4, in order to contact both the collet 2 and the lever 5, and so merely adapting this device by using a flexible extension between the handle 4 and the collet 2 would necessitate a flexible sleeve.

However, as yet no implementation of a flexible sleeve has been found that provides satisfactory performance.

Furthermore, it is often desirable to have a selection of lengths between the handle 4 and collet 2. For example, obstructions near the screw may prevent a user from reaching the screw with a short nut driver. On the other hand, a long nut driver may be unable to fit into closed spaces at the required angle, or simply be unwieldy when the nut is relatively unobstructed. The known nut drivers are available in various lengths, but for each desired length a new tool must be purchased. This leads to increased expense for users that require a variety of lengths.

Sockets and screwdrivers are known that are provided with extensions or extender arms. In these devices, the head of the socket or screwdriver is detachable from the handle, and the extension piece is simply a rigid bar with a connector at each end for attaching to the head and handle, respectively.

However, in the device shown in Figure 1, the sleeve 3 must extend from the collet 2 to the vicinity of the handle 4, in order to contact both the collet 2 and the lever 5, and so an extension piece would have to include at least the sleeve 3. Generally, the sleeve 3 and collet 2 are not separable, and so the collet 2 also would need to be part of the extension piece. Therefore, the extension piece would necessarily be more complicated than a known extension piece of a socket or screwdriver, and so the cost would not be significantly reduced.

Statement of Invention

The present invention relates to tools that address one or both of the above limitations of the known nut driver.

According to a first aspect of the present invention a tool comprises a collet chuck having open and closed states, suitable for gripping a target object in the closed state and releasing the target object in the open state, a control portion manually actuable by a user to control the opening and closing of the chuck, and an elongate section having first and second ends, the chuck and control portion being mounted on the first end.

This arrangement enables the device to be produced more easily, and with a reduced cost.

The elongate section may be a flexible portion elongate along an axis, the flexibility of the flexible portion permitting bending of the axis According to this arrangement, it is possible to permit rotation of the target object when the collet and the handle are not coaxial.

According to a second aspect of the present invention a tool comprises a collet chuck having open and closed states, suitable for gripping a target object in the closed state and releasing the target object in the open state, a control portion manually actuable by a user to control the opening and closing of the chuck, and an attachment portion connected to the chuck, adapted for detachable attachment to at least one of a handle and an extension portion.

According to this arrangement, it is possible to provide increased usefulness, while at the same time reducing cost, weight and the amount of storage space required.

Drawings Figure 1 illustrates a known nut driver.

Figure 2 shows a nut driver according to a first embodiment of the present invention.

Figure 3 illustrates the structure of the flexible portion shown in Figure 2.

Figure 4 shows a nut driver according to a second embodiment of the present invention.

Figure 5 shows an alternative embodiment of the control portion.

Figure 6 shows the device of Figure 2 in use.

Figure 7 shows a nut driver according to a third embodiment of the present invention.

Detailed Description

Embodiment 1 A specific embodiment of the present invention is shown in Figure 2. This embodiment is a nut driver 21 having a collet 22, similar to that described above in relation to the known nut driver. A sleeve 23 is coaxial with the collet 22 and moveable along the shared axis. The collet 22 and sleeve 23 each have a tapered portion 22d, 23d.

The collet 22 is rigidly attached to a threaded rod 24, with which it is coaxial, which in turn is rigidly attached to a first end 25a of an elongate section. The elongate section is a flexible portion 25. The flexible portion 25 comprises a plurality of layers of wound wire, with each layer being wound in an opposite sense, as shown in Figure 3.

The flexible portion 25 is elongate along an axis and has a second end 25b, in addition to the first end 25a. The flexibility of the flexible portion 25 permits bending of the axis. The first 25a and second 25b ends can be made to point in respective first and second directions that are not parallel by applying force to the flexible portion 25. Preferably, the flexible portion 25 is resiliently flexible. Preferably in the absence of an applied force the flexible portion 25 is straight. The flexible portion 25 is such that rotation of the second end 25b of the flexible portion about its axis is transmitted along the flexible portion to the collet 22.

The second end 25b of the flexible portion has an attachment portion 26, for attaching the flexible portion 25 to a handle 64. The handle 64 may also be detachable from the attachment portion 26. This allows for a reduction in the cost of producing the device, as the handle 64 does not need to be included in the device. There are various known handles for sockets and screwdrivers with standard fittings, which the attachment portion 26 could be adapted to fit.

An additional advantage of this is that a user can use a favourite handle, or use a handle particularly suited to the job at hand, such as a handle with a built-in ratchet. Furthermore, by permitting the attachment portion 26 to be detachable from the handle 64 the nut driver 21 will be lighter, take up less space and be easy to store.

The nut driver 21 also includes a control portion 27 that is actuable by a user to control the movement of the sleeve 23. In the present embodiment, the control portion includes a threaded barrel 27 between the sleeve 23 and the flexible portion 25. The barrel 27 sits coaxially around and is threadedly engaged on the threaded rod 24, such that rotation of the barrel 27 causes movement of the barrel 27 along the rod 24. Movement of the barrel 27 along the rod 24 towards the collet 22 brings the barrel 27 into pushing contact with the sleeve 23, thereby controlling the movement of the sleeve 23.

The barrel 27 may have a grip pattern, to facilitate manipulation by a user. A washer 28 may be provided between the barrel 27 and the sleeve 23.

In use, the control portion is actuated by rotating the barrel 27 so that the barrel 27 moves away from the head of the collet 22, allowing sleeve 23 to move away from the head of the collet 22. The collet 22 is thus put in an open state.

The collet 22 is then placed coaxially with a screw or other element to be turned, so that the opening 22c in the collet 22 receives the head of the screw or other element. The control portion is again actuated, but this time the barrel 27 is rotated in the opposite direction, so that the barrel 27 moves towards the head of the collet 22. The barrel 27 pushes against the sleeve 23, causing the sleeve 23 to move towards the head of the collet 22.

When the sleeve 23 is moved along the axis toward the head of the collet 23, the tapered portion 23d of the sleeve 23 exerts a force in an inward, radial direction on the tapered portion 22d of the collet 22. This force causes the sections 22a of the head of the collet 22 closer together and the gaps 22b to close. The size of the opening 22c between the sections 22a is therefore reduced, and the collet 22 will grip the head of the screw.

Meanwhile, as shown in Figure 6, the handle 64, which is attached to the second end 25b of the flexible portion 25 need not be coaxial with the collet 22 and screw 60, due to the flexibility of the flexible portion 25. The handle 64 is then turned about its axis by the user, and the torque from the handle 64 is transmitted along the flexible portion 25 to the collet 22, and therefrom to the head of the screw 60.

Therefore, the above embodiment provides a nut driver 21 that can be driven when the collet 22 and the handle 64 are not coaxial.

Embodiment 2 Figure 4 shows a device according to a second embodiment of the present invention.

This embodiment has a collet 42, a sleeve 43 and a control portion 47, arranged as described above in Embodiment 1. However this embodiment differs from Embodiment 1 in that the threaded rod 44, rather than being attached to a flexible portion 25, is attached to or formed with an attachment portion 46 that can be detachably attached to a handle or extension portion 47.

The attachment portion 46 can be any suitable element for attaching the threaded rod 44 to a handle or extension portion 47, provided the attachment is able to transmit a torque. For example a square drive, as used in a standard socket wrench set could be used.

The extension section 47 could be a flexible extension section, similar to that described above in relation to Embodiment 1, or could be a rigid extension section, similar to an extender of a socket wrench set. The handle or extension section 47 has an attachment section at one end, which can be detachably attached to the attachment section of the threaded rod.

The other end of the extension section 47 could have a further attachment section for attachment to a further extension section or a handle.

Alternatively, a handle could be permanently attached to the other end of the extension section 47.

According to this embodiment, a nut driver is produced that this adaptable for different situations depending on need, without requiring a complete nut driver for each situation. This has similar advantages to those described above regarding the handle of Embodiment 1, but in this case, the advantages are expected to be even more marked, as not only the handle, but also the extension portions can be shared with other tools. Therefore, the above embodiment leads to increased usefulness, while at the same time reducing cost, weight and the amount of storage space required.

Embodiment 3 A third embodiment of the present invention is shown in Figure 7. The third embodiment has a collet chuck 72, 73 and control portion 77 similar to those described in relation to Embodiment 1. The present embodiment also has a rigid elongate section 75 with first 75a and second 75b ends. The chuck 72, 73 and control portion 77 are attached to a first end 75a of the elongate section 75. The elongate section 75 could be a rod, for example.

Preferably, the chuck 72, 73 and control section 77 are closer to the first end 75a of the elongate section 75 than the second end 75b.

The second end 75b of the elongate section 75 can be permanently attached to a handle. As an alternative, the second end 75b can be detachably attached to a handle. In this case, an attachment portion 76, to which the handle can be detachably attached can be provided at the second end 75b of the elongate section 75.

According to the present embodiment, the control portion is close to the first end 75a of the elongate section 75, and away from the second end 75b of the elongate section 75. Accordingly, the control portion 77 is away from the handle if a handle is attached to the second end 75b of the elongate section 75.

In some arrangements having a handle attached, the control portion 77 is not actuable from the handle. For example, it may not be possible for a user to simultaneously grip the handle and actuate the control portion with the same hand, due to the positioning of the control portion.

The present embodiment is free of a mechanical linkage between (i.e. extending between) the first 75a and second 75b ends of the elongate section 75 for actuating the collet 72. Therefore, the sleeve 73 does not need to extend from the collet 72 to the second end 75b of the elongate section 75, or from the collet 72 to the handle. This has the effect of making the device easier to produce, and of reducing the cost of producing the device.

Variations and Alternative Embodiments Although embodiments of the present invention have been illustrated using the example of a nut driver, the present invention is not limited to nut drivers, and other devices using a collet are considered to fall within the scope of the present invention.

In the embodiments described above, both the collet 22, 42 and the sleeve 23, 43 have tapered portions 22d, 23d, 42d, 43d. However, any arrangement that allows the sleeve 23, 43 to control whether the collet 22, 42 is in an open or closed state can be used in the present invention. The specific structure of the collet chuck described herein could be replaced with any other collet chuck structure without departing from the scope of the present invention.

The exemplary embodiments describe a collet 22, 42 having three sections 22a, 42a and a hexagonal opening 22c, 42c for receiving hexagonal screw heads. However, the number of sections 22a, 42a is not particularly limited, as long as there are two or more. Similarly, the shape of the opening 22c, 42c is not particularly limited, and can be chosen to suite any desired shape of screw head or other element. Provided the collet 22, 42 is able to grip and turn the screw head, it is not necessary for the opening 22c, 42c to have the same shape as the screw head.

Throughout the description the object to be turned has been referred to as a screw, but any element could equally be turned, a non-limiting list includes bolts, nuts, and spark plugs.

The construction of the flexible portion 25 is not particularly limited, provided it is flexible and can transmit a torque applied at one end to the other end.

The above embodiments describe the flexible portion 25 as having an attachment portion 26 allowing the flexible portion to be attached to and detached from a handle 64. However, the flexible portion 25 could also be attached permanently to a handle 64.

The control portion could be any portion suitable for controlling the open or closed state of the collet 22, 42. lii an alternative embodiment the control portion and sleeve 23, 43 are integrally formed.

A further alternative embodiment is shown in Figure 5. In this embodiment the control portion includes a spring 55 and the circumferential surface of the sleeve 53a. The spring 55 is coaxial with the sleeve 53 and one end biases the sleeve 53 toward the collet 52 to hold the collet 52 in a closed state. The other end of the spring 55 is biased against the first end of the flexible portion, or some other suitable element 56 that is fixed relative to the collet 52. In use, the user grips the circumferential surface 53a and manually moves the sleeve 53 against the bias of the spring 55 to bring the collet 52 into an open state.

The collet 52 is then placed over the screw head, while the sleeve 53 is being retained by the user. When the collet 52 is in place over the screw head, the user releases the sleeve 53 so that it returns, under the action of the spring 55, towards the collet 52. The collet 52 thus returns to a closed state and grips the screw head. In this arrangement, the threaded rod can be replaced with an unthreaded rod 54.

Throughout, "detachable", "detachably attached", and similar terms are used to describe an arrangement in which an element can manually be attached, detached and reattached. This can be achieved by a connector as used in a square drive socket set or a magnetic connector, among others.

As used herein, manually actuable means manually engageable by a user, or directly and manually acted on by a user. For example, manually actuable includes gripping or pressing with the fingers.

Claims

Claims 1. A tool comprising: a collet chuck having open and closed states, suitable for gripping a target object in the closed state and releasing the target object in the open state, a control portion manually actuable by a user to control the opening and closing of the chuck, and an elongate section having first and second ends, the chuck and control portion being mounted on the first end.
2. A tool according to claim 1, wherein the chuck comprises: a collet, and a sleeve coaxial with the collet and moveable relative to the collet, arranged such that the position of the sleeve relative to the collet determines the open or closed state of the chuck, and wherein the control portion is actuable by a user to control the movement of the sleeve.
3. A tool according to claim 2, wherein the tool further comprises a threaded rod rigidly attached to the first end of the elongate section and the collet, and coxial with the chuck, andSthe control portion includes a threaded barrel that sits coaxially around and is threadedly engaged on the threaded rod, such that rotation of the barrel causes movement of the barrel along the rod.
4. A tool according to claim 2 wherein the control portion is integral with the sleeve.
5. A tool according to any preceding claim, wherein the elongate section is a flexible portion elongate along an axis, and the flexibility of the flexible portion permits bending of the axis.
6. A tool according to claim 5, wherein the flexible portion is resiliently flexible along its axis.
7. A tool according to claim 6, wherein the axis of the flexible portion is straight in the absence of any applied force.
8. A tool according to any one of claims 1 to 4, wherein the elongate section is rigid.
9. A tool according to claim 8, wherein the elongate section is a rod.
10. A tool according to any preceding claim, wherein the second end of the elongate section is attached or attachable to a handle.
11. A tool according to claim 10, further comprising, an attachment portion at the second end of the elongate section, the attachment portion being adapted to be detachably attached to the handle.
12. A tool according to claim 11 in combination with a said handle, said handle being adapted to be detachably attached to the attachment portion.
13. A tool according to claim 10 wherein the handle is permanently attached to second end of the elongate section.
14. A tool according to any preceding claim, wherein the control portion is away from the handle when the handle is attached.
15. A tool according to claim 14, wherein the control portion is not actuable from the handle
16. A tool according to any preceding claim, wherein the tool is free of a mechanical linkage extending between the first and second ends of the elongate section for actuating the collet.
17. A tool comprising: a collet chuck having open and closed states, suitable for gripping a target object in the closed state and releasing the target object in the open state, a control portion manually actuable by a user to control the opening and closing of the chuck, and an attachment portion connected to the chuck, adapted for detachable attachment to at least one of a handle and an extension portion.
18. A tool according to claim 17, wherein the chuck comprises: a collet, and a sleeve coaxial with the collet and moveable relative to the collet, arranged such that the position of the sleeve relative to the collet determines the open or closed state of the chuck, and wherein the control portion is actuable by a user to control the movement of the sleeve.
19. A tool according to claim 18, wherein the tool further comprises a threaded rod rigidly attached to the attachment portion and the collet, and coxial with the chuck, and the control portion includes a threaded barrel that sits coaxially around and is threadedly engaged on the threaded rod, such that rotation of the barrel causes movement of the barrel along the rod.
20. A tool according to claim 18 wherein the control portion is integral with the sleeve.
21. A tool according to any one of claims 17 to 20 in combination with a said handle, said handle being adapted for detachable detachment to the attachment portion.
22. A tool according to any one of claims 17 to 20 in combination with a said extension portion.
23. A tool according to claim 22, wherein the extension portion is a flexible extension portion elongate along an axis, and the flexibility of the flexible extension portion permits bending of the axis.
24. A tool according to claim 22, wherein the extension portion is rigid.
25. A tool substantially as hereinbefore described with reference to Figure 2 of the accompanying drawings.
26. A tool substantially as hereinbefore described with reference to Figures 2 and 3 of the accompanying drawings.
27. A tool substantially as hereinbefore described with reference to Figure 4 of the accompanying drawings.
28. A tool substantially as hereinbefore described with reference to Figure 5 of the accompanying drawings.
29. A tool substantially as hereinbefore described with reference to Figure 6 of the accompanying drawings.