AU726867B3 - Device for feeding a drain cleaning rod - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A PETTY PATENT Name of Applicant: Actual Inventor: Address for Service: Invention Title: FLUID INDUSTRIES PTY LTD STEPHEN ERIC WALKER CULLEN CO., Patent Trade Mark Attorneys, 239 George Street, Brisbane, QId. 4000, Australia.

DEVICE FOR FEEDING CLEANING ROD A DRAIN The following statement is a full description of this invention including the best method of performing it known to us: THE PRESENT INVENTION relates to a device for feeding a spiral wound drain cleaning rod. In particular the present invention is directed towards a device for feeding a spiral wound drain cleaning rod into a drain.

The use of drain cleaning rods to clean drains and pipes is well known.

Such rods are in the form of a helical steel spring and are commonly known as spiral wound drain cleaning rods. These rods are rotated and be fed into a pipe or drain in order to clear a blockage. The flexibility of the rods allows them to conform to bends in the drain or pipe. As a blockage may be some distance from the entrance to the drain a number of lengths of rod are typically joined together by steel couplings. Heavy duty drain cleaning rods are typically made in segments of 2.4 to 3.5m. When coupled together, this coupling interrupts the otherwise continuous spiral.

A cleaning tool such as a cutter for cutting through an obstruction in a drain or pipe is generally attached to the working end of the rod. Rotation of the rod can impart a cutting action to the cutter.

For heavy duty applications cleaning rods are rotated by a motor driven drain cleaner. An operator of the motor driven drain cleaner must have a degree of skill so as to avoid jamming of the cleaning tool at the working end of the rod in a blockage. The rods are typically manually fed into a drain by an operator. Typically the operator uses a device known as a feed fork which has a pair of tines for engaging the spirals or helices of the rod so as to urge the engaged rod in an axial direction. The fork can continually feed the rod providing the spiral or helix is continuous. However the spiral is not continuous due to the presence of the couplings. This interferes with the smooth feeding of the rod as when a coupling approaches the fork, the rod must be disengaged and reengaged on the other side of the coupling. This difficulty typically necessities the presence of two operators, one to operate the motor drive and the other to hand feed the rod into the drain.

It is therefore an object of the present invention to provide a device for feeding a spiral drain cleaning rod which may at least partially overcome the above disadvantage or provide the public with a useful choice.

According to a first broad form of the present invention there is provided a device for feeding a spiral drain cleaning rod, the device having two laterally spaced rod feed members, the feed members being movable between an engagement position in which they operatively engage the spiral of the rod and a free position and when at least one feed member is in the engagement position and the rod is rotated the rod is urged in an axial direction.

The rod feed members may be of any suitable shape or configuration so as to be able to engage the spiral of the rod such that rotational movement of the rod results in the rod being urged in an axial direction. The direction of axial movement depends upon the hand of the spiral thread and the direction of rotation. Removal of the rod can be accomplished by reversal of the direction of rod rotation such that the rod can be drawn out of the drain by operation of the feed members. In this case, the feed members may act to both withdraw the rod and to apply a cleaning motion to the spiral.

Alternatively, if desired, the device may be provided with means for disengaging the feed members from the rod such that the rod can be manually pulled from a drain.

The feed members may include a blade which can locate between successive spirals. The blades are typically swivably mounted. This enables the blades to accommodate movement of the rod and allows the device to feed rods having spirals of different pitches and hands.

Typically the device has an upper feed member which engages an upper section of the rod and a lower feed member which engages a lower section of the rod. Generally the lower feed member is gravity biased towards the rod. The upper feed member may be biased by biasing means such as a spring. When a joint or knuckle passes through the device the respective feed members are disengaged from the spiral, ride over the joint and reengaging the spiral as the joint passes. As there are two laterally spaced feed members the rod remains engaged with at least one feed member at all times.

Typically the device includes means to adjust the feed pressure transmitted to one of the feed members engaging with the rod. Generally the pressure can be adjusted between a minimum pressure in which the feed member provides no or minimal linear motion to the rod and a maximum pressure which provides a positive engagement sufficient to stall axial motion of the rod if it strikes a solid obstacle. Typically under normal conditions of use the pressure is set intermediate these two extremes such that the rod slips when an obstructions reached. This is advantageous as it alerts an operator to when an obstruction is reached. The operator can then decide whether to increase the drive pressure so as to increase the action of a cutting tool or the like. Alternatively if the operator believes there may be a risk of jamming the cutting tool he may choose to simply withdraw the rod.

The device is typically further provided with a means for engaging and/or securing to an open end of a drain to be cleaned. Typically the device may include an annular collar which can be placed in the open end of the drain.

In a preferred device of the present invention the device further includes a means for regulating a water supply into the drain to be cleaned.

Typically the water supply can be regulated such that the water level is at the top of the drain without overflow. Where the drain is a sewage pipe this can reduce sewage overflow. Also, when a blockage has been cleared this will be indicated by a sudden decrease in water level. After the blockage has been cleared the water supply can be increased so as to wash the rod as it is being withdrawn.

By way of example only, the present invention will now be described with reference to the following Figures in which: Figure 1 is a front perspective view of a preferred device of the present invention in a rod entry position; Figure 2 illustrates the device of figure 1 in a puissant in which a rod may be engaged and Figure 3 is a schematic view of the device of Figure 1 when in use feeding a drain cleaning rod into a drain.

Figure 1 illustrates a preferred device 11 of the present invention. The device has a lower collar 12 with a flared upper part 12a. The collar is dimensioned to snugly fit into a drain to be cleaned (This is illustrated in Figure A gap 13 is provided between the collar 12 and the upper section 14 of the device. This gap 13 allows visual inspection into the drain.

The upper section 14 of the device 11 has a curved tubular section 9 (see Figure 3) which functions to guide a drain cleaning rod 30 from a horizontal to a vertical orientation.

The upper section 14 includes a gate 15 which is slidably mounted on a pair of vertical slides 16, 17 such that it can be moved between an upper position as shown on Figure 1 and a lower position as shown in Figure 2. In the upper position the gate 15 defines an opening 18 which is of a size to allow a cutting tool attached to a drain cleaning rod to be passed therethrough. The gate 15 can be locked into the open position by a lock screw located on the back of the gate. After the cutting tool and rod are passed through opening 18, the gate can be closed into the position illustrated in figure 2. The gate 15 is fastened into the closed position by attaching a hold chain 20 to a gate lock pin 21. The device has a gate tension screw 22 which can be adjusted to control the hold down pressure of the gate. As the pressure is applied by a spring, the gate is able to move up and down in response to variations in the rod diameter or the presence of small kinks and the like.

The device 11 has an upper feed blade 23 and a lower feed blade 24 mounted thereto. Both blades are mounted for swivable movement. This allows the blades to accommodate movement of the rod as it passes therethrough. Still further, the swivable movement of the blades (through an 800 radius) enables the device to be used to feed either a right or left handed rod.

The upper blade 23 is mounted to the gate 15 such that it can be moved between an in use position and a non use position by lowering and raising the gate 15 respectively. The lower blade 24 can be removed from the device so as to allow manual withdrawal of a drain cleaning rod. This will be described in more detail below. The drive pressure of the upper blade 23 with a rod can be adjusted by means of a pressure adjustment screw 25. The tighter this screw, the firmer the drive pressure on the drain cleaning rod.

The screw can vary the pressure continuously from a minimum pressure in which the blade 23 provides minimal feeding drive to the rod and a maximum value which may be described as "100%" drive. In the minimum drive position if the rod hits an obstacle, feeding of the rod slips and the rod doesn't drive forward. This can avoid jamming of the cutting tool and damage to the rod.

Figure 3 illustrates the device 11 in use feeding a spiral wound drain cleaning rod 30 into a drain 31. Details of the engagement with the upper 23 and lower 24 feed blades are shown. The rod is gravity biased towards the lower blade 24. As a coupling 32 between two rods passes the lower blade 24 the blade 24 disengages the rod and rides up and over the coupling. The rod continues to be fed by means of the upper blade 23. As the coupling 32 passes, the blade 24 falls back into engagement with the spiral. The upper blade 23 is spring biased into engagement with the rod. As the coupling 32 passes the upper blade 23, the blade is forced up against the bias of the spring so as to allow the coupling 32 to ride past. When the coupling 32 has passed, the blade 24 is forced back into engagement with the spiral by the spring. In order to withdraw the rod from the drain, rotation of the rod may be reversed such that the blades feed the rod in the reverse direction. This action can clean the blades. Alternatively, the gate can be raised to disengage the rod from the upper blade 23, the lower blade 24 can be removed and the rod may be removed by hand.

The device is equiped with a coupling 33 to connect to a hose 35 for supplying water to the drain. A tap 34 is provided to regulate the water flow into the drain. Generaly, water flow is regulated so as to maintain a level of water at the top of the drain. This may prevent overflow of for example sewage from the pipe. Also, a sudden decrease in water level may indicate to an operator that an obstruction has been cleared. Still further water flow may assist in cleansing the rod during withdrawal.

It can be seen that the device of the present invention allows a spiral wound drain cleaning rod to be automatically fed into a drain to be cleaned.

Feeding of the rod is not interrupted by the presence of couplings or joints between lengths of rod. The drive pressure may be varied such that the rod 7 is able to slip should it strike an obstacle. The device can enable a drain cleaning operation to be carried out by a single operator.

It will be appreciated that various changes or modifications may be made to the invention as described and claimed herein without departing from the spirit and scope of the invention.

Claims (3)

1. A device for feeding a spiral drain cleaning rod, the device having two laterally spaced rod feed members, the feed members being movable between an engagement position in which they operatively engage the spiral of the rod and a free position and in use the fluid members are spaced axially along the rod so that at least one feed member remains engaged when a rod joiner passes through the device and when the at least one feed member is in the engagement position and the rod is rotated the rod is urged in an axial direction.

2. The device of claim 2, wherein the feed members are blades mounted for swivable movement.

3. The device of claim 1, substantially as hereinbefore described with reference to the Figures. DATED this 7 th day of September 2000 FLUID INDUSTRIES PTY LTD By their Patent Attorneys CULLEN CO. "A( ITT 4