GB2507253B

GB2507253B - Gas heating appliance controller including biasing means which bias the controller to a normal operating range

Info

Publication number: GB2507253B
Application number: GB1215382.1A
Authority: GB
Inventors: Simon Stonier Christopher
Original assignee: Trustees Of Hearth Products Pension Scheme
Current assignee: Trustees Of Hearth Products Pension Scheme
Priority date: 2012-08-29
Filing date: 2012-08-29
Publication date: 2019-07-24
Anticipated expiration: 2032-08-29
Also published as: GB2507253A; GB201215382D0

Description

Gas Heating Appliance Controller Including Biasing Means Which Bias The Controller To A Normal Operating Range

The present invention relates to a gas heating appliance controller, particularly but not exclusively a gas heating appliance controller for a gas fire.

Conventionally, it is known to provide a controller for a gas fire including a rotatable or a slidable knob which permits ignition of a gas flame and control of gas flow to the flame between a high limit and a low limit. Typically, conventional controllers provide only visual indication to a user of the position of the controller (for example, by markings) and do not provide any tactile feedback to a user.

Typically, a conventional controller is provided as part of a so called “engine assembly”. The engine assembly is fitted into a fireplace surround, and a decorative fire front fitted over the engine assembly. Conventionally, it has been found that following fitting of the engine assembly into the fireplace surround, the controller must be calibrated to ensure correct operation, requiring the presence of an appropriately trained technician, which increases the cost of installation. In particular, it is the control of gas flow at the low limit which is problematic and requires calibration.

According to a first aspect of the present invention, there is provided a gas heating appliance controller for a gas fire as defined in claim 1 of the claims.

According to a second aspect of the present invention there is provided a gas heating appliance engine assembly for a gas fire as defined in claim 26 of the claims.

According to a third aspect of the present invention, there is provided a gas heating appliance as defined in claim 27 of the claims.

According to a fourth aspect of the present invention, there is provided a method of controlling a gas heating appliance as defined in claim 28 of the claims.

Other features of the invention are as defined in any of the dependent claims.

An embodiment of the present invention will now be described, by way of example only, and with reference to the accompanying drawings, in which:-

Fig. 1 is a perspective view of a gas heating appliance engine assembly for a gas fire;

Fig. 2 is a relatively enlarged front view of part of a gas heating appliance controller for a gas fire, including a controller which is shown in an unlit condition, and a high flame condition;

Fig. 3 is a view similar to that of Fig 2, but showing the controller in an ignition condition;

Fig. 4 is a view similar to that of Figs 2 and 3, but showing the controller in a low flame condition; and

Fig. 5 is a view similar to that of Figs 2 to 4, but showing the controller in a shut-off condition.

Figs. 1 to 5 show a gas heating appliance 10 comprising a gas heating appliance engine assembly 11. It will be understood that the gas heating appliance 10 as shown in Fig 1 is incomplete, and could include, for example, a fire front (not shown) which in an installed condition is mounted in front of the engine assembly 11. The gas heating appliance 10 could, for example, be a gas fire or a room heater.

The engine assembly 11 includes a controller 12, a burner assembly 54 and a firebox 55.

The controller 12 is movable into and out of a normal operating range, and includes biasing means 20, 22 for biasing the controller 12 to the normal operating range.

The controller 12 includes a control member 14 which is movable between an unlit position, an ignition position, a low flame position, a high flame position and a shut-off position. The controller 12 includes ignition biasing means 20 which bias the control member 14 away from the ignition position and shut-off biasing means 22 which bias the control member 14 away from the shut-off position.

In the example shown, the ignition biasing means 20 and the shut-off biasing means 22 both comprise the same resiliently deformable member in the form of a spring 24. In other examples (not shown) the ignition biasing means 20 and the shut-off biasing means 22 could be separate, and could comprise, for example, separate resiliently deformable members.

The controller 12 includes a mounting 18 for the control member 14. The control member 14 is slidably mounted to the mounting 18, which includes a mounting member 19 in the form of a plate. In the example shown, the mounting member 19 also provides a mounting for other components of the engine assembly 11 such as the burner assembly 54 and the firebox 55.

The control member 14 includes an in use upwardly extending connecting part 56. The control member 14 includes a knob part 16 which extends laterally from the in use upper end of the connecting part 56.

The mounting 18 includes channelling 52. The connecting part 56 is located within the channelling 52 for slidable movement therein.

The mounting 18 includes a plurality of retaining members 58 in the form of screws which extend through slots 60 defined in the control member 14. The retaining members 58 retain the control member 14 against the mounting member 19, the retaining members 58 and the slots 60 permitting slidable movement of the control member 14 relative to the mounting member 19.

The control member 14 defines a control aperture 62. The mounting 18 includes a spring pin mounting member 32 which projects forwardly from the mounting member 19 into the control aperture 62. The mounting 18 includes a spring pin 28 which extends substantially vertically through a hole (not shown) defined in the spring pin mounting member 32. The spring pin 28 is able to move substantially vertically upwards and downwards in the hole relative to the spring pin mounting member 32.

The mounting 18 includes a first, upper in use spring retaining member 34 in the form of an enlarged head at an upper end in use of the spring pin 28. The mounting 18 includes a second, lower in use spring retaining member 36 in the form of a plate which defines a hole (not shown) through which the spring pin 28 is slidably movable.

The mounting 18 includes a spring pin limit member 64 in the form of a plate which is fixed to the in use lower end of the spring pin 28.

The spring 24, which in this example is a compression coil spring, is located over the spring pin 28 between the upper spring retaining member 34 and the lower spring retaining member 36.

The controller 12 includes a low flame position adjuster 80, which includes a threaded pin which is adjustably locatable in a threaded hole 82. In the example shown, the threaded pin comprises the spring pin 28, and the threaded hole 82 is defined by the spring pin limit member 64.

The low flame position adjuster 80 includes an adjuster lock 86, to lock the position of the threaded pin 28 in the threaded hole 82. The adjuster lock 86 includes a threaded locking member 78, which could be in the form of a set screw, which locates in a threaded lock hole 84 defined by the spring pin limit member 64.

The control member 14 includes a pair of upwardly directed shoulder parts 66 which project laterally into the control aperture 62, forming a lower, relatively narrow part 68 of the control aperture 62. The upwardly directed shoulder parts 66 are freely slidably movable relative to the spring pin mounting member 32, and the spring pin limit member 64; the lower spring retaining member 36, however, is located above the upwardly directed shoulder parts 66 and can engage thereon as will be described below.

The control member 14 includes a downwardly directed shoulder part 74 which projects laterally into the control aperture 62, forming an upper, relatively narrow part 72 of the control aperture 62. The control aperture 62 also includes a middle, relatively wide part 70 between the lower narrow part 68 and the upper narrow part 72.

The control member 14 includes an in use upper spring compression surface 50 which in this example is formed on a forwardly projecting in use upper spring compression part 51 of the control member 14.

The controller 12 includes a gas flow valve actuator 46 which is movable to regulate gas flow to the burner assembly 54. The controller 14 includes a sloping flow valve actuation surface 48 against which the gas flow valve actuator 46 abuts. As the control member 14 moves slidably vertically upwards and downwards, the flow valve actuation surface 48 moves the gas flow valve actuator 46 to regulate the gas flow.

The control member 12 includes a shut-off switch 38 in the form of a micro-switch, which when actuated shuts off the flow of gas to the burner assembly 54. The control member 14 includes a shut-off switch actuation surface 42 formed on an upper surface of a laterally projecting part 76 of the control member 14.

The controller 12 includes an ignition switch 40 in the form of a microswitch, which when actuated permits gas flow to the burner assembly 54, and causes ignition of the gas in the burner assembly 54. The control member 14 includes an ignition switch actuation surface 44 formed on a lower surface of the laterally projecting part 76 of the control member 14.

In use, the controller 12 is initially in an unlit condition, with the control member 14 in an unlit position as shown in Fig 2. In this condition, the upper spring retaining member 34 is spaced from (or may be just touching) the upper spring compression surface 50, the spring 24 is holding both the spring pin limit member 64 and the lower spring retaining member 36 against the spring pin mounting member 32, the shut-off switch actuation surface 42 is not actuating the shut-off switch 38, the ignition switch actuation surface 44 is not actuating the ignition switch 40 and the flow valve actuator 46 is in relatively extended position, contacting a lower part of the sloping flow valve actuation surface 48.

To light the burner assembly 54, the controller 12 is moved to the ignition condition as shown in Fig 3, with the control member 14 in an ignition position. To move the controller 12 to the ignition condition, the user slides the knob part 16 downwards, sliding the control member 14 downwards until the upper spring compression surface 50 contacts the upper spring retaining member 34 and begins to compress the spring 24. At this point, the user will experience tactile feedback from the resistance force provided by the spring 24, which increases as the spring 24 is progressively compressed. The control member 14 is slid downwardly to the ignition position, in which the spring pin limit member 64 is spaced from the spring pin mounting member 32. In the ignition condition, the ignition switch actuation surface 44 contacts the ignition switch 40, permitting gas flow to the burner assembly 54, and causing ignition of the gas in the burner assembly 54. In the ignition condition, the flow valve actuator 46 is in a less extended position, contacting an upper part of the sloping flow valve actuation surface 48.

When a flame has been established, the user releases the knob part 16, releasing the spring 24 which moves the control member 14 upwardly to the low flame position, and the controller 12 to the low flame condition as shown in Fig 4. In this condition, the spring 24 is again holding both the spring pin limit member 64 and the lower spring retaining member 36 against the spring pin mounting member 32, the upper spring compression surface 50 is in contact with the upper spring retaining member 34, the shut-off switch actuation surface 42 is not actuating the shut-off switch 38 and the ignition switch actuation surface 44 is not actuating the ignition switch 40. In the low flame condition, the flow valve actuator 46 is in a middle extended position, contacting a middle part of the sloping flow valve actuation surface 48.

If the user should now move the knob part 16 downwards, the control member 14 will be moved downwards and the upper spring compression surface 50 which is in contact with the upper spring retaining member 34 will begin to compress the spring 24, giving tactile feedback from the resistance force provided by the spring 24, which increases as the spring 24 is progressively compressed. Thus the controller 12 of the invention provides a tactile feedback to the user when the controller is being moved beyond the low flame condition towards the ignition condition.

To increase the heat output from the heating appliance 10 and/or the size of the flame, the user moves the knob part 16 upwards, moving the control member 14 upwards, in turn moving the flow valve actuation surface 48 upwards, permitting the flow valve actuator 46 to extend, increasing the gas flow to the burner assembly 54, until the controller 12 reaches the high flame condition and the control member 14 reaches the high flame position. A feature of the arrangement of the present invention is that the adjustment of the heat output and/or the flame size between the low and high flame conditions is substantially continuous, due to the cam-like action of the flow valve actuation surface 48 in actuating the flow valve actuator 46.

In the high flame condition, the upper spring retaining member 34 is spaced from the upper spring compression surface 50, the upwardly directed shoulder parts 66 are abutting the lower spring retaining member 36, the spring 24 is holding both the spring pin limit member 64 and the lower spring retaining member 36 against the spring pin mounting member 32, the shut-off switch actuation surface 42 is not actuating the shut-off switch 38, the ignition switch actuation surface 44 is not actuating the ignition switch 40 and the flow valve actuator 46 is in a more extended position, contacting a lower part of the sloping flow valve actuation surface 48.

If the user continues to move the knob part 16 upwards, the upwardly directed shoulder parts 66 engage underneath and lift the lower spring retaining member 36 and compress the spring 24, so that the user experiences tactile feedback from the resistance force provided by compressed spring 24 that the high flame condition has been reached.

Thus, the controller 12 provides tactile feedback to the user when the user moves the controller 12 out of the range between the low flame and the high flame condition. The controller 12 does not include biasing means for biasing movement of the control member 14 between the low flame position and the high flame position.

The controller 12 can be moved to a shut-off condition if the user moves the knob part 16 upwards from the high flame condition so that the upwardly directed shoulder parts 66 lift the lower spring retaining member 36, compressing the spring 24. In the shut-off condition, with the control member 14 in the shut-off position, the upper spring retaining member 34 is spaced from the upper spring compression surface 50, the spring 24 is holding the spring pin limit member 64 against the spring pin mounting member 32, the lower spring retaining member 36 is spaced from the spring pin mounting member 32, the shut-off switch actuation surface 42 actuates the shut-off switch 38, shutting off the flow of gas to the burner assembly 54, and the flow valve actuator 46 is in the most extended position, contacting a lower part of the sloping flow valve actuation surface 48.

The user need only hold the control member 14 in the shut-off position momentarily and can then release the knob part 16, so that the control member 14 returns to the unlit position, and the controller 12 returns to the unlit condition.

There is thus provided a controller 12 which provides tactile feedback to the user when the controller is in the correct normal operating condition between the high flame condition and the low flame condition. Advantageously, the controller 12 is of simple and robust construction. The same spring 24 provides the biasing means which bias the control member 14 from the ignition position to the low flame position, provide resistance to movement from the unlit position to the ignition position, provide resistance to movement from the high flame position to the shut-off position and bias the control member 14 from the shut-off position to the unlit position.

Advantageously, the low flame position can be set and locked before delivery to the user, as follows. Following assembly of the engine assembly 10, the controller 12 is set to the low flame condition. Initially, the low flame position adjuster 80 is in an adjustment condition, in which the locking member 78 permits the spring pin 28 to be adjusted by screwing into or out of the threaded hole 82, thus altering the length of the pin 28 and hence the position of the control member 14 relative to the mounting member 19 and the flow valve actuator 46, and the distance that the control member 14 must travel before the upper spring compression surface 50 comes into contact with the upper spring retaining member 34. When the flame characteristics are correct, the low flame position adjuster 80 is set to a locked condition by tightening the locking member set screw 78 in the lock hole 84 against the spring pin 28. Further calibration is not then required after installation, so that a technician trained in calibration is not required at installation.

The operating characteristics of the controller 12 are set by the relative positions of the upwardly directed shoulder parts 66, the length of the spring pin 28 and the length and compressive characteristics of the spring 24. The high flame position is determined by the depth of the spring pin mounting member 32 and the location of the upwardly directed shoulder parts 66, both of these being fixed during the design and manufacture of the controller 12.

All of the aforesaid factors affecting the operating characteristics can be set during testing of the engine assembly prior to shipping to the installation site, so that calibration of the engine assembly on-site by a trained technician is not required. Furthermore, although the engine assembly 10 shown in the drawings includes the firebox 55, an advantage of the invention is that the controller 12 can be calibrated without the firebox 55 being present.

Various other modifications could be made without departing from the scope of the invention. The various components of the controller could be of any suitable size and shape, and could be formed of any suitable material. Any suitable biasing means could be used. The biasing means could comprise any suitable number and type of resiliently deformable components.

In a further embodiment (not shown), the controller 12 include a powered actuator for moving the control member 14, which could be electrically powered, and could include a remote control switch mechanism, permitting operation by a user from a distance.

There is thus provided a controller for a gas heating appliance which biases the controller to operate in a range between the low flame condition and the high flame condition.

Claims

1. A gas heating appliance controller for a gas fire, the controller being movable into and out of a normal operating range, in which the normal operating range includes, at one end, a low flame condition, at another end, a high flame condition, and the normal operating range extends between the low flame condition and the high flame condition, the controller including biasing means for biasing the controller to the normal operating range, wherein the biasing means do not bias the controller between the low flame condition and the high flame condition in the normal operating range.

2. A controller according to claim 1, in which the biasing means provide a tactile feedback to a user when the user moves the controller out of the range.

3. A controller according to claims 1 or 2, in which the biasing means operate automatically.

4. A controller according to any of the preceding claims, in which the controller is movable to an ignition condition, and the biasing means bias the controller away from the ignition condition.

5. A controller according to any of the preceding claims, in which the controller is movable to a shut-off condition and the biasing means bias the controller away from the shut-off condition.

6. A controller according to any of the preceding claims, in which the controller is movable to an unlit condition and the biasing means bias the controller towards the unlit condition.

7. A controller according to claim 6 when dependent on claim 5, in which the biasing means bias the controller from the shut-off condition towards the unlit condition.

8. A controller according to claims 6 or 7 when dependent on claim 4 or any claim dependent thereon, in which, in the unlit condition, the biasing means bias the controller away from the ignition condition towards the unlit condition.

9. A controller according to claim 4 or any claim dependent thereon, in which, in the ignition condition, the biasing means bias the controller away from the ignition condition towards the low flame condition.

10. A controller according to any of the preceding claims, in which the controller includes a control member which is movable between an unlit position, an ignition position, a low flame position, a high flame position and a shut-off position, the biasing means including ignition biasing means which bias the control member away from the ignition position, and shut-off biasing means which bias the control member away from the shut-off position.

11. A controller according to claim 10, in which the ignition biasing means bias the control member from the ignition position to the low flame position.

12. A controller according to claims 10 or 11, in which the ignition biasing means provide resistance to movement from the unlit position to the ignition position.

13. A controller according to any of claims 10 to 12, in which the ignition biasing means comprise a resiliently deformable member, which may be in the form of a spring.

14. A controller according to any of claims 10 to 13, in which the shut-off biasing means provide resistance to movement from the high flame position to the shut-off position.

15. A controller according to any of claims 10 to 14, in which the shut-off biasing means bias the control member from the shut-off position to the unlit position.

16. A controller according to any of claims 10 to 15, in which the shut-off biasing means comprise a resiliently deformable member, which may be in the form of a spring.

17. A controller according to any of claims 10 to 16, in which the ignition biasing means comprise the shut-off biasing means.

18. A controller according to claim 17 when dependent on claims 13 and 16, in which the ignition biasing means and the shut-off biasing means comprise the same resiliently deformable member, which may be in the form of a spring.

19. A controller according to any of claims 10 to 18, in which the controller includes a mounting for the control member.

20. A controller according to claim 19, in which the control member is slidably mounted to the mounting.

21. A controller according to claims 19 or 20, in which the mounting includes a spring pin, on which the resiliently deformable member is mounted.

22. A controller according to any of the preceding claims, in which the controller includes a low flame position adjuster, which may be movable between an adjustment condition and a locked condition.

23. A controller according to claim 22, in which the low flame position adjuster includes a threaded pin which is adjustably locatable in a threaded hole.

24. A controller according to claim 23 when dependent on claim 21 or any claim dependent thereon, in which the threaded pin comprises the spring pin.

25. A controller according to claims 23 or 24, in which the low flame position adjuster includes an adjuster lock, to lock the position of the threaded pin in the threaded hole.

26. A gas heating appliance engine assembly for a gas fire, the engine assembly including a controller as defined in any of the preceding claims.

27. A gas heating appliance, the gas heating appliance including a controller as defined in any of claims 1 to 25.

28. A method of controlling a gas heating appliance, the method including providing a controller as defined in any of claims 1 to 25.