GB2544105A

GB2544105A - Telescopic wand for a vacuum cleaner

Info

Publication number: GB2544105A
Application number: GB1519659.5A
Authority: GB
Inventors: David Lambert Adam; Andrew Mcluckie Paul
Original assignee: Dyson Technology Ltd
Current assignee: Dyson Technology Ltd
Priority date: 2015-11-06
Filing date: 2015-11-06
Publication date: 2017-05-10
Anticipated expiration: 2035-11-06
Also published as: US20170127899A1; GB201519659D0; GB2544105B; CN106821146A; JP6362658B2; JP2017094069A

Abstract

A telescopic wand for a vacuum cleaner comprises an inner tube 2, an outer tube 3, and a catch assembly . The catch assembly comprises a catch 41 and a leaf spring 42. The catch 41 is pivotally mounted to the outer tube 3 and comprises a button 43 and a locking stub 44. The leaf spring 42 extends between the catch 41 and the outer tube 3 and exerts a biasing force on the catch 41. The catch 41 pivots between a lock position and an unlock position. The catch 41 is biased by the biasing force to the lock position, and depressing the button 43 causes the catch 41 to pivot to the unlock position. The locking stub 44 engages the inner tube 2 when the catch 41 is in the lock position such that movement of the inner tube 2 relative to the outer tube 3 is prevented. The locking stub 44 then disengages the inner tube 2 when the catch 41 is in the unlock position such that movement of the inner tube 1 relative to the outer tube 3 ispermitted.

Description

Telescopic Wand for a Vacuum Cleaner

The present invention relates to a telescopic wand for a vacuum cleaner.

The telescopic wand of a vacuum cleaner may comprise an inner tube, an outer tube, and a catch assembly for locking the position of the inner tube relative to the outer tube. Unfortunately, the catch assembly is often bulky and/or the assembly of wand is relatively complex.

The present invention provides a telescopic wand for a vacuum cleaner, the wand comprising an inner tube, an outer tube, and a catch assembly, wherein: the catch assembly comprises a catch and a leaf spring; the catch is pivotally mounted to the outer tube and comprises a button and a locking stub; the leaf spring extends between the catch and the outer tube and exerts a biasing force on the catch; the catch pivots between a lock position and an unlock position, the catch is biased by the biasing force to the lock position, and depressing the button causes the catch to pivot to the unlock position; and the locking stub engages the inner tube when the catch is in the lock position such that movement of the inner tube relative to the outer tube is prevented, and the locking stub disengages the inner tube when the catch is in the unlock position such that movement of the inner tube relative to the outer tube is permitted.

By employing a leaf spring that extends between the catch and the outer tube, a relatively low profile may be achieved for the catch assembly. The catch assembly of a conventional wand may comprise a coil spring that is located beneath the button or above the locking stub. However, the use of a coil spring increases the overall height of the catch assembly. Additionally, the coil spring requires a wall beneath or above the catch against which the spring can abut. By employing a leaf spring, a shallower profile for the spring itself may be achieved. Additionally, the wall of the outer tube against which the spring abuts in order to bias the catch may be located alongside the catch rather than beneath or above the catch. As a result, a catch assembly having a lower profile may be achieved.

The biasing force may act in a downward direction. As a result, the leaf spring pulls the catch down onto the pivot mount of the outer tube. Consequently, the catch pivots immediately upon depressing the button. This then has the advantage that less travel of the button is required in order to move the catch from the lock position to the unlock position, and thus a more compact arrangement may be achieved. By contrast, if the biasing force were to act in an upward direction, the catch would be lifted slightly off the pivot mount of the outer tube. Consequently, when the button is depressed, the catch does not immediately pivot but instead moves downward until the catch engages the pivot mount. Only at this point does the catch begin to pivot. The button is therefore required to travel a further distance in order to move the catch from the lock position to the unlock position.

The leaf spring may pass beneath the button. Moreover, the leaf spring may be secured at one end to the underside of the catch and at an opposite end to the inside of the outer tube. As a result, the leaf spring is able to exert a downward biasing force on the catch without the need for a wall passing over the top of the catch, which would other compromise the size of the wand.

The wand may be configured such that the catch is flush with the outer tube when in the lock position. This then has the advantage that the catch does not inadvertently snag on items (e.g. upholstery or curtains) during use.

The wand may be configured such that the catch does not contact the inner tube when in the unlock position. This then has the advantage that the catch does impede movement of the inner tube relative to the outer tube. By contrast, the catch of a conventional wand may comprise a rocking element sandwiched between the inner tube and the outer tube. Depressing the button of the catch then causes the rocking element to rock on the surface of the inner tube. Whilst a relatively compact arrangement may be achieved with this type of catch, the rocking element continuously contacts the inner tube when the catch is in the unlock position. As a result, movement of the inner tube relative to the outer tube is less smooth owing to the friction that arises from the rocking element.

In the present description, the terms ‘upward’, ‘downward’, ‘above’ and ‘below’ are made with reference to the central longitudinal axis of the tubes. Consequently, the terms ‘upward’ and ‘downward’ should be understood to mean in directions away from and towards the longitudinal axis. Furthermore, where a first feature is described as being located ‘above’ or ‘below’ a second feature, this should be understood to mean that the first feature is located further from or closer to the longitudinal axis.

In order that the present invention may be more readily understood, an embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of a telescopic wand in accordance with the present invention;

Figure 2 is a partially exploded view of the telescopic wand;

Figure 3 is a side view of a sectional slice through the telescopic wand with a catch in a lock position; and

Figure 4 is the same view as Figure 3 but with the catch in an unlock position.

The telescopic wand 1 of Figures 1 to 4 comprises an inner tube 2, an outer tube 3, and a catch assembly 4.

The inner tube 2 is roughly cylindrical in shape. The top of the tube 2, however, is flattened and comprises a plurality of projections 21. The gap between each pair of projections 21 defines a recess 22 into which a locking stub 44 of the catch assembly 4 projects; this is described below in more detail. A first end of the inner tube 2 is attachable to a cleaner head or accessory (not shown), and a second opposite end of the inner tube 2 is received within the outer tube 3. The inner tube 2 slides relative to the outer tube 3 along a central longitudinal axis 23, and a seal 24 is provided at the second end of the inner tube 2 so as to minimise leaks between the inner tube 2 and the outer tube 3.

The outer tube 3 is cylindrical in shape. A first end of the outer tube 3 surrounds the inner tube 2, and a second opposite end is attachable to a handle or hose (not shown). An opening 31 is formed in the top of the outer tube 3 and is located towards the first end of the tube 3. The outer tube 3 comprises a pair of lugs 32 located on opposite sides of the opening 31, and a stop 33 located at one end of the opening 31. As explained below, the lugs 32 act as fulcrums for the catch assembly 4, whilst the stop 33 acts to limit movement of the catch assembly 4.

The catch assembly 4 comprises a catch 41 and a leaf spring 42.

The catch 41 is a unitary body that comprises a button 43 and a locking stub 44. The catch 41 is pivotally mounted to the outer tube 3 at a pivot point 45 located between the button 43 and the locking stub 44. More particularly, the catch 41 comprises a pair of recesses 46 located on opposite sides of the catch 41. The lugs 32 of the outer tube 3, which are roughly triangular in shape, are seated in the recesses 46 and act as fulcrums for the catch 41.

The leaf spring 42 is secured to the underside of the catch 41 and to the inside of the outer tube 3. More specifically, the catch 41 comprises a channel into which a first end of the leaf spring 42 is inserted. Likewise, the outer tube 3 comprises a channel formed on the inside of the outer tube 3 into which a second opposite end of the leaf spring 42 is inserted. The leaf spring 42 therefore extends between the catch 41 and the outer tube 3. In extending between the catch 41 and the outer tube 3, the leaf spring 42 passes beneath the button 43 of the catch 41. The leaf spring 42 applies a biasing force F to the catch 41. The biasing force F acts in a downward direction at a point located between the pivot point 45 and the locking stub 44. As a consequence, the biasing force F pulls the locking stub 44 downwards towards the inner tube 2.

The catch 41 pivots between a lock position (Figure 3) and an unlock position (Figure 4). The catch 41 is biased by the biasing force F of the leaf spring 42 to the lock position. When the catch 41 is in the lock position, the locking stub 44 projects into a recess 22 between two of the projections 21 of the inner tube 2. Movement of the inner tube 2 relative to the outer tube 3 is then prevented. In particular, when the inner tube 2 is moved to the left or right, the locking stub 44 abuts one of the projections 21 so as to prevent any further movement. The catch 41 is moved to the unlock position by depressing the button 43. When the button 43 is depressed, the catch 41 pivots about the pivot point 45 against the biasing force F of the leaf spring 42. As a result, the locking stub 44 pivots upwards. The locking stub 44 is then lifted clear of the recess 22 and the projections 21. The inner tube 2 is then free to slide left and right relative to the outer tube 3. When the button 43 is released, the leaf spring 42 pulls the locking stub 44 downwards. Depending on the position of the inner tube 2, the locking stub 44 is pulled down into one of the recesses 22 or onto one of the projections 21. In the former case, the catch 41 is returned to the lock position. In the latter case, further movement of the inner tube 2 causes the locking stub 44 to slide on top of the projection 21 until such time as the locking stub 44 aligns with and snaps into one of the recesses 22, at which point the catch 41 is returned to the lock position.

As can be seen in Figures 3 and 4, the stop 33 of the outer tube 3 limits both the upward and downward movement of the catch 41. When the button 43 is depressed and the locking stub 44 pivots upwards, the locking stub 44 abuts the underside of the stop 33 when the locking stub 44 is clear of the projections 21. Further downward travel of the button 43 is therefore prevented and thus the user is provided with an indication that the catch 41 is in the unlock position. When the button 43 is released and the leaf spring 42 pulls the locking stub 44 downwards, the catch 41 abuts the top of the stop 33 when the catch 41 is level with the outer tube 3. Consequently, although the locking stub 44 projects into the recess 22 when the catch 41 is in the lock position, there is nevertheless a small clearance between the bottom of the locking stub 44 and the top of the inner tube 2. By stopping the catch 41 at a position level with the outer tube 3, the catch 41 is flush with the outer tube 3 when in the lock position. This then has the advantage that the catch 41 does not inadvertently snag on items, such as upholstery or curtains, during use. Additionally, by limiting the travel of the catch 41 when moving to the lock position, less travel of the button 43 is required in order to move the catch 41 to the unlock position.

The provision of a leaf spring 42 that extends between the catch 41 and the outer tube 3 enables a relatively low profile to be achieved for the catch assembly 4. The catch assembly of a conventional wand may comprise a coil spring that is located beneath the button or above the locking stub. However, the use of a coil spring increases the overall height of the catch assembly. Additionally, the coil spring requires a wall beneath or above the catch against which the spring can abut. By employing a leaf spring 42, a shallower profile for the spring itself may be achieved. Additionally, the wall of the outer tube 3 against which the spring abuts in order to bias the catch 41 is located alongside the catch 41 rather than beneath or above the catch 41. As a result, a catch assembly 4 having a lower profile may be achieved.

The catch of a conventional wand may comprise a central rocking element to which the button and the locking stub are connected. The rocking element is then sandwiched between the inner tube and the outer tube. Depressing the button of the catch causes the rocking element to rock on the surface of the inner tube. Whilst a relatively compact arrangement may be achieved with this type of catch, the rocking element continuously contacts the inner tube when the catch is in the unlock position. As a result, movement of the inner tube relative to the outer tube is less smooth owing to the friction that arises from the rocking element. With the telescopic wand 1 described herein, the catch 41 is pivotally mounted to the outer tube 3. Consequently, when the button 43 is depressed and the catch 41 pivots to the unlock position, no part of the catch 41 need contact the inner tube 2. As a result, smoother movement of the inner tube 2 relative to the outer tube 3 may be achieved.

The biasing force F exerted by the leaf spring 42 on the catch 41 acts in a downward direction. As a result, the locking stub 44 is pulled downwards by the leaf spring 42. Conceivably, the biasing force exerted by the leaf spring 42 may act in an upward direction. In this instance, the button 43 is pushed upwards by the leaf spring 42. This may be achieved, for example, by having a leaf spring 42 that exerts a biasing force directly beneath the button 43. The catch 41 and/or the outer tube 3 may then include a stop so as to limit the upward travel of the button 43. Alternatively, the manner in which the catch 41 is pivotally mounted to the outer tube 3 may be adapted such that the catch 41 is not pushed off the pivot mount by the leaf spring 42. However, if the biasing force were to act in an upward direction, the catch 41 would be lifted slightly off the lugs 32 (or other pivot mount) of the outer tube 3. This behaviour is inevitable due to tolerances in the catch 41 and the outer tube 3. Consequently, when the button 43 is depressed, the catch 41 does not immediately pivot but instead moves downward until the catch 41 engages the lugs 32 of the outer tube 3. Only at this point does the catch 41 begin to pivot. The button 43 is therefore required to travel a further distance in order to move the catch 41 from the lock position to the unlock position. When the biasing force F acts in a downward direction, on the other hand, the catch 41 is pulled down onto the lugs 32 of the outer tube 3. Consequently, when the button 43 is depressed, the catch 41 pivots immediately. Less travel of the button 43 is therefore required in order to move the catch 41 from the lock position to the unlock position. As a result, a more compact arrangement may be achieved. In particular, a smaller clearance may be employed between the outer tube 3 and the inner tube 2.

The button 43 comprises a raised portion which serves as a visual indicator of where on the catch 41a user should depress. A visual indicator may, however, be achieved by other means, e.g. an indented portion or other surface feature. Moreover, the catch 41 may fail to comprise a visual indicator. Accordingly, whilst the button 43 illustrated in the Figures comprises a raised portion, it should be understood that the button 43 is merely that part of the catch 41 that, when depressed, causes the catch 41 to pivot from the lock position to the unlock position, and that the button 43 may be raised, indented or flat.

In addition to being relatively compact, the catch assembly 4 of the telescopic wand 1 is relatively easy to assemble. Assembly begins by inserting the second end of the leaf spring 42 into the channel of the outer tube 3. The first end of the leaf spring 42 is then pushed upwards through the opening 31 in the outer tube 3; this can be achieved by reaching inside the first end of the outer tube 3. The catch 41 is then secured to the leaf spring 42 by inserting the first end of the leaf spring 42 into the channel formed on the underside of the catch 41. The leaf spring 42 is then gently released, causing the catch 41 to be pulled down into the opening 31 in the outer tube 3. The lugs 32 in the outer tube 3 are then seated in the recesses 46 in the catch 41. At this point the catch 41 is pivotally mounted to the outer tube 3 and may be moved between the lock and unlock positions. Finally, the button 43 is depressed so as to move the catch 41 to the unlock position and the inner tube 2 is inserted into the outer tube 3.

Claims

1. A telescopic wand for a vacuum cleaner, the wand comprising an inner tube, an outer tube, and a catch assembly, wherein: the catch assembly comprises a catch and a leaf spring; the catch is pivotally mounted to the outer tube and comprises a button and a locking stub; the leaf spring extends between the catch and the outer tube and exerts a biasing force on the catch; the catch pivots between a lock position and an unlock position, the catch is biased by the biasing force to the lock position, and depressing the button causes the catch to pivot to the unlock position; and the locking stub engages the inner tube when the catch is in the lock position such that movement of the inner tube relative to the outer tube is prevented, and the locking stub disengages the inner tube when the catch is in the unlock position such that movement of the inner tube relative to the outer tube is permitted.

2. A telescopic wand as claimed in claim 1, wherein the biasing force acts in a downward direction.

3. A telescopic wand as claimed in claim 1 or 2, wherein the leaf spring passes beneath the button.

4. A telescopic wand as claimed in any one of the preceding claims, wherein the leaf spring is secured at one end to the underside of the catch and at an opposite end to the inside of the outer tube.

5. A telescopic wand as claimed in any one of the preceding claims, wherein the catch is flush with the outer tube when in the lock position.

6. A telescopic wand as claimed in any one of the preceding claims, wherein the catch does not contact the inner tube when in the unlock position.