Patent Application
20130098742
The present invention generally relates to knob safety devices, and more particularly relates to a knob safety assembly for preventing children from activating a cooking element.
A common concern among parents is preventing children from playing with hazardous household items such as cooking devices, electrical outlets, and cupboard contents to prevent children from exposing themselves to potentially harmful conditions. Although electrical outlets and cupboards may be positioned to be out of reach of children, cooking devices, such as a stove, are generally low to the ground and easily reachable, and are therefore of particular concern. Numerous prior art safety devices for cooking devices have been proposed; however, many of the prior art devices have proven easily circumvented or cumbersome to use. One of the better prior art devices is shown in U.S. Pat. No. 5,931,150. However, the device of the '150 patent must be removed in order for the knob to be actuated, and then replaced when done, which has proven less than desirable in some situations. As such, there remains a need for alternative designs of stove knob safety devices.
A knob safety assembly is operative to restrict depression of a cooking element control knob. The knob safety assembly includes a bezel assembly and a blocking plate that is disposed inside of the bezel assembly, with the blocking plate movable relative to the bezel assembly between raised and recessed positions. When the blocking plate is in the raised position, the blocking plate restricts depression of the corresponding cooking element control knob; when the blocking plate is in recessed position, the blocking plate allows depression of the control knob. The bezel assembly includes an outer bezel defining one or more angled camming surfaces, and also an inner bezel. Rotation of the inner bezel with respect to the outer bezel about a rotational axis slides an ear of the blocking plate along the camming surface to effect displacement of the blocking plate along the rotational axis. The inner bezel is releasably locked from rotating with respect to the outer bezel, and the inner bezel engages the blocking plate to constrain the blocking plate against movement along the rotational axis when the inner bezel is rotationally locked with respect to the outer bezel. A cooking device utilizing the knob safety assembly is also disclosed.
Of course, the present invention is not limited to the above features and advantages. Indeed, those skilled in the art will recognize additional features and advantages upon reading the following detailed description, and upon viewing the accompanying drawings.
a is a view of a knob safety assembly having its blocking member in a blocking position.
b is a view of the knob safety assembly having its blocking member in a retracted position.
As will be discussed in greater detail below, a knob safety assembly 50 is operative to restrict depression of a cooking element control knob 40 of a cooking device (e.g., stove 10). The knob safety assembly 50 includes a bezel assembly 51 and a blocking plate 56 that is movable relative to the bezel assembly 51 between a raised or “blocking” position, in which the blocking plate 56 restricts depression of the control knob 40, and a recessed or “retracted” position, in which the blocking plate 56 allows depression of the control knob 40. Although the knob safety assembly 50 is discussed in connection with a stove 10, it is understood that the stove 10 is only an example cooking device, and that the knob safety assembly 50 is applicable to a wide variety of cooking devices, such as griddles and the like, and other non-cooking devices having similar push-in type control knobs.
Referring to
Referring to
Each control knob 40 has an associated switch 34. The switch 34 is disposed mostly behind control panel 32 for safety reasons and attached thereto via brackets or the like. The switch post 38 of switch extends through a corresponding hole in control panel 32. By pressing and turning the switch post 38, via control knob 40, an operator is able to make the necessary adjustments to the cooking elements 30 via the switch 34 (e.g., adjusting an intensity of a respective cooking element 32).
To operate the stove 10, a user would turn control knobs 40 on the control panel 32 associated with the stove 10. In order to be able to turn the control knobs 40 from an “off” position, it is necessary to first push the control knob 40 (and consequently switch post 38) inwardly from an “out” position to an “in” position, before turning the control knob 40. Thus, a user needs to push in on the control knob 40 before it can be turned. By pushing in and twisting the control knob 40, the user is able to turn on the associated switch 34 and therefore activate one or more associated cooking elements 30. Additional details of the construction and operation of the stove 10, and variations thereof, are well known in the art and are not discussed further herein except as to assist in understanding the present invention.
The stove 10 includes one or more a cooking device knob assemblies 46 that each include a switch 34 (with its switch post 38 and control knob 40) and a knob safety assembly 50. The knob safety assembly 50 is disposed between the control knob 40 and the face 33 of control panel 32 (see
In general, the knob safety assembly 50 includes a bezel assembly 51 and a blocking plate 56 (see
The sidewall also advantageously includes a least one peripheral groove 66 that extends peripherally (e.g., circumferentially) around the central axis X of the outer bezel 52. These grooves 66 extend into the sidewall proximate rear flange 65 and the corresponding ribs 58a-b, and extend across an arc of limited extent. The end of the grooves 66 may advantageously include a ramp 67 that may be used to guide ears 72 of blocking plate 56, as discussed further below. The ramps 67 are advantageously angled at the same angle relative to rear face 62 as the corresponding camming surfaces 57. A depression 69 may optionally be located at one end of the groove 66 proximate the ramp 67.
The inner bezel 54 is disposed at least partially inside the outer bezel 52, and is rotatably coupled to the outer bezel 52 for rotation about rotational axis X that is parallel to, or coaxial with, the switch post 38. The inner bezel 54 includes at least one tongue 80, and each tongue 80 is received into a respective peripheral groove 66 in the sidewall of outer bezel 52. The inter-engagement of tongues 80 and grooves 66 mates the inner bezel 54 to the outer bezel 52, but allows relative rotation therebetween, and may also define the range of rotation of the inner bezel 54 with respect to the outer bezel 52 (see arc A of
The sidewall of outer bezel 52 also optionally includes one or more inwardly open channels 90 extending generally parallel to axis X. The optional channels 90 may be positioned to accept the tongues 80 and guide them to their respective grooves 66, for some or all of the tongues 80, during assembly of the inner bezel 54 to the outer bezel 52. The inner bezel 54 also advantageously includes a flexible moveable tab 76 that selectively disengages from teeth 64 to selectively rotationally unlock the inner bezel 54 from the outer bezel 52.
The outer bezel 52 and inner bezel 54 collectively define an annular cavity 82 within the bezel assembly 51 that houses the angled camming surfaces 57, tongues 80, and peripheral grooves 66. Axial slots 78 of the inner bezel 76 provide openings into the cavity 82, and the inner bezel 54 engages the blocking plate 56 via the axial slots 78. The inner bezel 54 may optionally include a circumferential gripping surface 84.
The blocking plate 56 is disposed inside of and is advantageously circumferentially surrounded by the bezel assembly 51. The blocking plate 56 has a central opening 70 to receive switch post 38 and also has a plurality of outwardly extending ears 72. Each of the ears 72 extends through a respective axial slot 78 of the inner bezel 54 to engage a respective one of the camming surfaces 57. Each of the ears 72 may include ear flanges 75a-b that define an ear slot 74 (see
Each of the plurality of ears 72 is in sliding abutment with a respective one of the angled camming surfaces 57. As discussed above, the outer bezel 52 includes a plurality of teeth 64 that engage with a movable tab 76 of the inner bezel 54 to restrict rotation of the inner bezel 54. When the tab 76 engages the teeth 64, the inner bezel 54 is rotationally locked with respect to the outer bezel 52, and the slots 78 constrain the blocking plate 56 against axial or rotational movement. Tab 76 is movable to selectively rotationally unlock the inner bezel 54 from the outer bezel 52 by disengaging from the teeth 64. When the inner bezel 54 is unlocked and rotates with respect to the outer bezel 52 (by the operator), the slots 78 advance the ears 72 of the blocking plate 56 along their respective camming surfaces 57 to effect axial translational movement of the blocking plate 56 along the rotational axis X, due to the rotational movement of the blocking plate 56, between the blocking position (see
In the blocking position, the blocking plate 56 restricts depression of the control knob 40, and thus switch post 38, to prevent children from undesirably turning on the cooking elements 30. The blocking plate 56 is spaced apart from the rear face 62 of the outer bezel 52 (and the control panel 32 of the stove 10) by a distance D1 in the blocking position. Conversely, in the retracted position, the blocking plate 56 is spaced apart from the rear face 62 of the outer bezel 52 (and the control panel 32 of the stove 10) by a distance D2, which is less than the distance D1, thereby allowing depression of the control knob 40 and the switch post 38. The blocking plate 56 is also movable to a plurality of intermediate positions between the illustrated blocking and retracted positions. In the intermediate position the blocking plate 56 is spaced apart from the rear face 62 by a distance within a range defined by D1-D2.
In the example of
The knob safety assembly 50 is advantageously formed of a suitable plastic material such as polycarbonate. The knob safety assembly 50 may be constructed so as to be generally translucent or transparent, or may be opaque, or a mix thereof, as is desired. Further, the knob safety assembly may optionally be colored, in whole or part, such as to match a color of the stove 10 for example.
The present invention may, of course, be carried out in other ways than those specifically set forth herein without departing from essential characteristics of the invention. The present embodiments are to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.
