GB2470929A

GB2470929A - Removal tool and spanner for installing and uninstalling a central heating pump

Info

Publication number: GB2470929A
Application number: GB0909955A
Authority: GB
Inventors: Antony Pugh; Michael Long
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-06-10
Filing date: 2009-06-10
Publication date: 2010-12-15
Also published as: GB0909955D0

Abstract

The tool 200 includes a handle portion 204 and a first threaded portion at a first end of the tool. A reaction member 212 is configured for axial movement on the tool. A locking formation axially restrains the reaction member in use. The tool may have a stepped external threaded portion 206 having a first threaded portion 208 of a first diameter d and a second threaded portion 210 having a second diameter D located between the first threaded portion and the handle portion. The reaction member 212 may include an internal thread 216 to engage with the second threaded portion. The ratchet spanner 300 has a nut engagement formation 308 having an open mouth 310 to receive a nut 302, the engagement formation defining a first face 318 and a second face 312 opposed to and substantially parallel to the first face, defining a nut insertion direction I. The first face includes a first abutment region 326, the second face includes a second abutment region 328, in which the first abutment region is positioned further along the nut insertion direction than the second abutment region. The second face also defines a recess 330 substantially opposite the first abutment region with the second abutment region positioned between the recess and the mouth. An alternative combined ratchet spanner includes first and second ratchet spanners oppositely oriented.

Description

A pump removat toot, spanner and method of instatting and uninstatting a centrat heating pump The present invention is concerned with a pump removal tool and spanner. More specifically, the present invention is concerned with a central heating pump removal tool and ratchet spanner for removal of a central heating pump.

Central heating boilers employ a separate pump to pump water through them. Such pumps are installed in the water line upstream of the boiler such that they can be easily replaced without having to tamper with the boiler itself Conventional central heating pumps comprise a pump body, an inlet and an outlet.

The inlet and outlet are aligned to define a flow axis through the pump. The inlet and outlet are formed from pipe sections having external thread formations for engagement with union nuts which secure the inlet and outlet to a water pipe.

The pump housing houses the moving pump parts, and often comprises a bleed valve to enable the installer to remove any unwanted air from the pump and pipe. Such bleed valves comprise an internally threaded orifice having an externally threaded bleed valve body engaged and sealed therewith. The pump may therefore be bled by partially or completely unfastening the bleed valve body.

A problem during the installation and uninstallation of central heating pumps is the difficulty in reacting the torque that needs to be applied to fasten and undo the union nuts. Union nuts are fastened tightly to prevent water leaks, and therefore when a significant amount of torque is applied to the nut, the entire pup may rotate about the flow axis instead of the union nut rotating relative to the pump. The user may attempt to hold the pump housing in his hand, however this is often awkward. It is also ineffective as the level arm of the spanner engaging the union nut projects ftirther from the union nut axis than the housing, thus providing a smaller moment arm.

The user may attempt to overcome this problem by providing a further spanner fastened to the other union nut to react the applied torque. This is not ideal because simultaneous and careful alignment of both spanners on each of the nuts is required, which is difficult. Furthermore, the other union nut may have been loosened, thus not providing an adequate position to react the torque applied to the first nut.

Furthermore, union nuts require several turns to undo. The problem with known single piece spanners is that they need to be removed and reengaged with the nut several times before it can be undone. An alternative to this is to use a ratchet spanner, which employs a non-return mechanism between a handle and the spanner head. Such devices are expensive and complex.

It is an object of the invention to provide an improved pump removal tool and spanner.

According to a first aspect of the invention there is provided a method of installing or uninstalling a central heating pump comprising the steps of: providing a central heating pump comprising a flow channel having a rotational mechanical connection defining a first axis, the pump further comprising a first rotational mechanical formation defining a second axis at an angle to the first axis, providing a tool having a second rotational mechanical formation, engaging the first and second rotational mechanical formations such that the removal tool projects from the pump, applying a torque between the tool and the rotational connection to install or uninstall the pump.

Preferably the first rotational mechanical formation is a threaded bleed valve formation. Preferably a part of the bleed valve is removed to expose the first rotational mechanical formation.

Preferably the rotational mechanical connection comprises a union nut. Preferably the first and second formations are complementarily threaded.

Preferably the tool comprises a reaction member, the pump comprises a housing, and the step of engaging the first and second rotational mechanical formations comprises the step of abutting the reaction member against the housing.

Preferably the reaction member is movable on the tool, and the step of abutting the reaction member against the housing comprises the step of moving the reaction member along the tool to abut the housing. Preferably the reaction member is threaded to the tool.

According to a second aspect of the invention there is provided a central heating pump installation and removal tool comprising: a handle portion, a first threaded portion of a first diameter defined at a first end of the removal tool, a reaction member configured for axial movement on the tool, and, a reaction member locking formation configured to axially restrain the reaction member in use.

Preferably the tool comprises: a stepped external threaded portion at the first end of the removal tool, which stepped external threaded portion comprises: the first threaded portion and a second threaded portion of a second diameter greater than the first diameter, the second threaded portion positioned between the first threaded portion and the handle portion, wherein the reaction member locking formation comprises an internal thread defined on the reaction member engaged with the second threaded portion.

Preferably the reaction member has a diameter at least three times the diameter of the second threaded portion.

Preferably the reaction member is substantially in the shape of a disc.

According to a third aspect of the invention there is provided a ratchet spanner comprising: a nut engagement formation having an open mouth to receive a nut, the engagement formation defining a first face and a second face opposed to and substantially parallel the first face, the first and second faces defining a nut insertion direction, the first face comprising a first abutment region, the second face comprising a second abutment region, in which the first abutment region is positioned further along the nut insertion direction than the second abutment region, and, the second face defines a recess substantially opposite the first abutment region with the second abutment region positioned between the recess and the mouth.

Preferably the nut engagement formation defines a female nut outer profile between the first face and the second face.

Preferably the recess describes an arc.

According to a fourth aspect of the invention there is provided a combined ratchet spanner comprising a first ratchet spanner part having a first nut receiving area and a second ratchet spanner part having a second nut receiving area, the first and second spanner parts being oppositely oriented to provide ratcheting actions in opposite rotational directions, the first and second spanner parts being attached with their respective nut receiving areas substantially coincident.

Preferably the first and second ratchet spanner parts are ratchet spanners according to the third aspect of the invention.

Preferably a plate is provided disposed between the ratchet spanner parts at least partially delimiting the nut receiving areas.

An example pump removal tool, spanner and method of installing and uninstalling a central heating pump will now be described with reference to the accompanying drawings in which: Figure 1 is a perspective view of a boiler and central heating pump, Figure 2 is a perspective view of the central heating pump of figure 1, Figure 3 is a perspective view of the central heating pump of figure 1 with the bleed valve removed, Figure 4 is a perspective view of a central heating pump removal tool in accordance with the second aspect of the present invention, Figure 5 is a perspective view of the central heating pump of figure 1 being removed in accordance with the first aspect of the present invention, Figure 6a is a plan view of a first spanner in accordance with the third aspect of the present invention in a first position, Figure 6b is a plan view of the spanner of figure 6a rotated to a second position, Figure 6c is a plan view of the spanner of figure 6a rotated to a third position, Figure 6d is a plan view of the spanner of figure 6a rotated to a fourth position, Figure 7a is a plan view of a spanner in accordance with the fourth aspect of the present invention, and, Figure 7b is a side view of the spanner of figure 7a.

Referring to figure 1, a domestic central heating boiler 100 is shown which has a water feed pipe 102 for the delivery of cold water from supply pipe 106 for heating in a flow direction F. A central heating pump 104 is connected in the feed pipe 102 to provide a cold water flow from a supply pipe 106 in the direction F. Turning to figure 2, the central heating pump 104 is shown in more detail. The pump 104 comprises a flow channel section 108 and a pump housing 109. The flow channel section 108 has an inlet 110 and an outlet 112 which connect to the supply pipe 106 and the feed pipe 102 respectively. The inlet 110 and outlet 112 define external threaded formations (not shown) and are attached to the pipes 106, 102 via union nuts 114, 116 respectively. It will be appreciated that details of the attachment are known in the art, and that the pump can be installed and uninstalled to the pipes 106, 102 by fastening and unfastening the union nuts 114, 116 as required with an appropriate spanner.

It will be noted that the inlet 110 and the outlet 112 define a flow axis A. The pump housing 109 contains the moving parts of the pump, and comprises an externally facing bleed valve orifice 118 defining an internal thread 120 (see figure 3).

A bleed valve body 122 comprises an external thread and is engaged with the internal thread 120. The bleed valve body 122 defined a tool engagement formation 124 for a screwdriver to enable it to be removed from the housing 109. The bleed valve orifice 118 defines a bleed valve axis B, which is perpendicular to the flow axis A. Figure 3 shows the pump 104 with the bleed valve body 122 removed.

Turning to figure 4, a pump removal tool 200 in accordance with the present invention is shown. The pump removal tool 200 comprises a cylindrical shaft 202 of a diameter D and defining a handle portion 204 at a first end and a stepped, threaded portion 206 at a second, opposite end.

The stepped, threaded portion 206 comprises a first threaded portion 208 of a diameter d, smaller than the diameter D. The stepped, threaded portion also defines a second threaded portion 210 of diameter D. The first threaded portion 208 is configured to engage the bleed valve internal thread 120-i.e. the diameter d is equal to that of the bleed valve orifice 118.

The pump removal tool 200 comprises a reaction member 212 in the shape of a disc.

The reaction member 212 defined a central, axial, internal through bore 214 with an internal thread 216. The bore 214 is of diameter D and as such can engage the second threaded portion 210.

In use, when a user wishes to install or uninstall the pump 104, the bleed valve body 122 is removed from the bleed valve orifice 118 to expose the thread 120 (per figure 3). The first threaded portion 208 of the tool 200 is engaged with the thread 120.

Once in place, the reaction member 212 is rotated on the second threaded portion 210 to abut a face of the member 212 against the pump housing 109 as shown in figure 5.

Once secure, the handle portion 204 is held, and can be used to react any torque applied to the union nuts 114, 116 via a spanner 218.

Turning to figure 6a, a spanner 300 is shown engaging a union nut 302. The spanner 300 comprises a handle portion 304 and a head portion 306. The head portion comprises a nut engaging formation 308. The nut engaging formation 308 defines a mouth 310 into which the union nut 302 is slidable in an insertion direction I to engage the nut engaging formation 308.

The nut engaging formation 308 is defined by four major faces 312, 314, 316, 318 joined by three minor faces 320, 322, 324. The major faces 312 and 318 are parallel, offset by an across-flats distance AF and joined by the remaining faces 314, 316.

Each of the adjacent major faces are at an angle of 60 degrees to each other, thus forming a part of a hexagon. The minor faces 320, 322, 324 are smaller than the major faces 312, 314, 316, 318 but also equal in length and join adjacent major faces at an angle of 30 degrees to both. Therefore, the nut engaging formation 308 described part of a hexagon with chamfered edges, which is the same as the external profile of the union nut 302.

The major face 318 does not extend through the full length of its corresponding face of the union nut 302. Instead, the major face 318 extends a partial length of the corresponding face of the union nut 302 to define a first abutment region 326.

The major face 312 extends for the full length of its corresponding face of the union nut 302, and defines a second abutment region 328. The first abutment region 326 is positioned further along the nut insertion direction I than the first abutment region 328. Therefore the first abutment region 326 and the second abutment region 328 are arranged to contact opposite ends of opposing flats of the union nut 302.

The major face 312 defines a recess 330 between the second abutment region 328 and the adjacent minor face 320. The recess described an arc. The function of the recess 330 will be described below.

In order to apply a torque to the nut 302, the spanner 300 is rotated in a direction 332.

The abutment regions 326, 328 engage their corresponding faces of the nut 302 and hence torque is transmitted.

Once the user has turned the nut 302 through a desired amount, the spanner 300 can be repositioned by rotating it in the opposite direction 334. As shown in figure 6b, the spanner pivots about the end of the abutment region 326. Due to the presence of the recess 330, a corner 332 of the nut 302 can move into the recess 330 allowing the spanner 300 to rotate relative to the nut 302 in direction 334.

The spanner 300 continues to be turned in figure 6c until the faces 312, 318 align with parallel flats of the nut 302 and the nut 302 can enter the mouth 310 to engage the spanner 300. Torque can then be applied in the direction 332 and transmitted to the nut 302.

In this way, the user can fasten or unfasten the nut 302 by making a part-turn and "ratcheting" the spanner around to start again. This is useful if space is restricted and does not require total disengagement of the spanner 300 with the nut 302.

Referring to figure 7a, a spanner 400 comprises a first spanner part 402 and a second spanner part 404, both of which are similar to the spanner 300. The spanner part 402 is shown in hidden line for clarity. The spanner parts 402, 404 are stacked as shown in figure 7b. In use, either the first spanner part 402 or the second spanner part 404 may be engaged with a nut (not shown). Optionally, only one of the spanner parts can be used to engage the axial end of the nut, thus providing the ratcheting action as described for the spanner 300. The rotational direction in which the nut ratchets can be changed by flipping the spanner 400 over to engage the other of the spanner parts 402, 404.

Alternatively, both spanner parts 402, 404 can be engaged with the nut simultaneously to provide a normal (non-ratcheting) spanner action.

Variations fall within the scope of the present invention.

For example, if desired, simultaneous engagement of the spanner parts 402, 404 may be prevented by providing a plate therebetween.

The reaction member 212 may be securable on the shaft 202 via a radial screw or similar to hold it in place.

The reaction member 212 may be of any external shape, e.g. square or splined to aid turning.

The tool 200 may comprise a threaded portion of a different diameter on the handle end 204 to enable the tool to be used with two different bleed valve thread sizes. A cap or sheath may be provided to cover the unused end when the tool 200 is in use.

Claims

Claims 1. A method of installing or uninstalling a central heating pump comprising the steps of: providing a central heating pump comprising a flow channel having a rotational mechanical connection defining a first axis, the pump further comprising a first rotational mechanical formation defining a second axis at an angle to the first axis, providing a tool having a second rotational mechanical formation, engaging the first and second rotational mechanical formations such that the removal tool projects from the pump, applying a torque between the tool and the rotational connection to install or uninstall the pump.
2. A method according to claim 1 in which the first rotational mechanical formation is a threaded bleed valve formation.
3. A method according to claim 1 or 2 comprising the step of removing a part of the bleed valve to expose the first rotational mechanical formation.
4. A method according to any preceding claim in which the rotational mechanical connection comprises a union nut.
5. A method according to any preceding claim in which the first and second formations are complementarily threaded.
6. A method according to any preceding claim in which the tool comprises a reaction member, the pump comprises a housing, and the step of engaging the first and second rotational mechanical formations comprises the step of abutting the reaction member against the housing.
7. A method according to claim 6 in which the reaction member is movable on the tool, and the step of abutting the reaction member against the housing comprises the step of moving the reaction member along the tool to abut the housing.
8. A method according to claim 7 in which the reaction member is threaded to the tool.
9. A central heating pump installation and removal tool comprising: a handle portion, a first threaded portion of a first diameter defined at a first end of the removal tool, a reaction member configured for axial movement on the tool, and, a reaction member locking formation configured to axially restrain the reaction member in use.
10. A central heating pump installation and removal tool according to claim 9 comprising: a stepped external threaded portion at the first end of the removal tool, which stepped external threaded portion comprises: the first threaded portion and a second threaded portion of a second diameter greater than the first diameter, the second threaded portion positioned between the first threaded portion and the handle portion, wherein the reaction member locking formation comprises an internal thread defined on the reaction member engaged with the second threaded portion.
11. A central heating pump installation and removal tool according to claim 9 or 10 in which the reaction member has a diameter at least three times the diameter of the second threaded portion.
12. A central heating pump installation and removal tool according to claim 11 in which the reaction member is substantially in the shape of a disc.
13. A ratchet spanner comprising: a nut engagement formation having an open mouth to receive a nut, the engagement formation defining a first face and a second face opposed to and substantially parallel the first face, the first and second faces defining a nut insertion direction, the first face comprising a first abutment region, the second face comprising a second abutment region, in which the first abutment region is positioned further along the nut insertion direction than the second abutment region, and, the second face defines a recess substantially opposite the first abutment region with the second abutment region positioned between the recess and the mouth.
14. A ratchet spanner according to claim 13 in which the nut engagement formation defines a female nut outer profile between the first face and the second face.
15. A ratchet spanner according to claim 13 or 14 in which the recess describes an arc.
16. A combined ratchet spanner comprising a first ratchet spanner part having a first nut receiving area and a second ratchet spanner part having a second nut receiving area, the first and second spanner parts being oppositely oriented to provide ratcheting actions in opposite rotational directions, the first and second spanner parts being attached with their respective nut receiving areas substantially coincident.
17. A combined ratchet spanner according to claim 16 in which the first and second ratchet spanner parts are ratchet spanners according to any of claims 13 to 15.
18. A combined ratchet spanner according to claim 16 or 17 further comprising a plate disposed between the ratchet spanner parts at least partially delimiting the nut receiving areas.