DESC:FIELD
The present disclosure relates to a speed control unit for a kitchen appliance. More particularly, the present disclosure relates to a speed control unit for a mixer grinder.
DEFINITION
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used indicate otherwise.
PULSE function: The term ‘PULSE function’ refers to a setting of the mixer grinder that let the grinder run at a relatively higher speed, as long as a knob/button/switch is held on this position. This setting gives a control over the grinder function, especially when short power bursts are required to prevent over-grinding.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Conventional kitchen appliances such as mixer grinders employ a rotary knob for changing the speed at which food items are ground. The rotary knob is a mechanical device connected to a motor of the grinder, and by whose rotation the speed of the motor can be varied. The rotary knobs are equipped with springs and conductive rubber elements for the overall working of the knobs. However, the additional elements not only add to the cost, maintenance and complexity of the knobs but also are affected by the continuous rotation of the knob thus damaging the functioning of the knob.
Some conventional mixer grinders are provided with separate graduations marking a pulse function. Rotating the knob towards the marked graduation allows the actuation of the pulse function. Other grinders are provided with separate buttons configured to actuate the motors to facilitate the pulse function.
On the other hand, some mixer grinders are provided with haptic switches to add to the aesthetics of the grinder and reduce the effects on the knob. The switches are provided with illuminated indicators that indicate the various speeds of the motor. However, these switches are quite bulky and require good electrical contact for their work. Further, studies have been conducted wherein it was observed that since the participants or the user were more familiar with the rotary knobs, they tended to operate the mechanical switches faster than the haptic switches.
Another type of speed control unit, conventionally seen, includes piano key switches which can be of either rocker type or latching type of switch. Each speed level has a piano key switch dedicated thereto. Although these types of switches do not include the provision of springs or rubbers, they are very noisy when pressed because of the mechanical contact between the switch components. Further, it has been observed, that sometimes the switches do not work when the speed levels are being changed, thereby resulting in undesirous processing of the food content.
There is, therefore, a need to alleviate the aforementioned drawbacks.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
An object of the present disclosure is to provide a speed control unit for a kitchen appliance and a method for operating the unit.
Another object of the present disclosure is to provide a speed control unit for a kitchen appliance that has a simple yet cost-effective configuration.
Yet another object of the present disclosure is to provide a speed control unit for a kitchen appliance that has relatively improved sensibility.
Another object of the present disclosure is to conserve electricity by using the kitchen appliance for the required amount of time.
Yet another object of the present disclosure is to provide a speed control unit for a kitchen appliance that can be used conveniently and with ease.
Another object of the present disclosure is to provide a speed control unit for a kitchen appliance that prevents damage of the motor assembly of the kitchen appliance.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure envisages a speed control unit for a kitchen appliance having a motor. The speed control unit comprises a first switch configured to be in electrical communication with the motor. The speed control unit further comprises a second switch having a shaft defined by a first shaft portion configured to extend from an operative first surface of the second switch, and a second shaft portion configured to extend from an operative second surface of the second switch. The second shaft portion of the second switch is configured to abut the first switch in an operative configuration of the control unit. The speed control unit has a housing configured to be located on the second switch. The housing has a set of first graduations marked thereon corresponding to a set of motor speeds, and at least one second graduation corresponding to a desired function marked thereon. The housing further has an aperture configured to receive the operative first portion of second switch therein. The speed control unit has a rotary knob rotatably provided on the housing. The knob is configured to abut the operative first portion of second switch.
The knob is configured to be pressed at the second graduation, in an operative first configuration of the control unit, to linearly displace the shaft to facilitate abutment of the second shaft portion with the first switch and actuate the motor at a speed corresponding to the desired function. The knob is further configured to be rotated along the set of first graduations, in an operative second configuration of the control unit, to facilitate actuation of the motor at the corresponding motor speeds.
In an embodiment, the speed control unit includes a potentiometer attached to the first switch. The potentiometer is configured to be in electrical communication with the motor. The potentiometer is configured to detect the angular displacement of the rotary knob, and is further configured to vary the voltage input to the motor based on the sensed angular displacement, to run the motor at the desired motor speed.
In another embodiment, the knob is configured to be locked at the second graduation to prevent angular displacement of the knob in an operative configuration of the motor at the second graduation.
In yet another embodiment, the shaft is a spring-loaded shaft configured to facilitate displacement of the first switch to its original position, thereby disengaging the motor.
In still another embodiment, the desired function is selected from a group consisting of a pulse function, whip function, blend function, coarse function, boost function, chop function or any other functionality in the kitchen appliance.
In an embodiment, the first switch is a tactile switch.
In another embodiment, the second switch is a cam switch.
In yet another embodiment, a printed circuit board is fastened to the motor. The printed circuit board is configured to facilitate mounting of the first switch thereon.
In an embodiment, the set of first graduations includes 0th speed level, slow speed level, 1st speed level, 2nd speed level and 3rd speed level, the 0th speed level being the level at which the motor is deactivated and 3rd speed level being the highest speed level.
In another embodiment, the potentiometer is configured to increase the voltage input to the motor when the knob is angularly displaced from 0th to slow, from slow to 1st level, from 1st level to 2nd level, from 2nd level to 3rd level, and is further configured to decrease the voltage input from 3rd level to 2nd level, 2nd level to 1st level, 1st level to slow level and from slow level to 0th level
In yet another embodiment, the length of the first portion of the shaft is more than the length of the second portion of the shaft in the second switch.
In still another embodiment, the housing includes a recess configured on an operative outer surface thereof to facilitate nesting of the knob on the housing.
The present invention further envisages a method for operating the speed control unit. The method comprises the following steps:
• locating the knob at the second graduation;
• pressing the knob in an operative downward direction at the second graduation to enable linear displacement of the shaft in an operative first direction to facilitate abutment of the second shaft portion with the first switch to actuate the motor at a speed corresponding to the desired function; and
• releasing the knob to enable linear displacement of the shaft in an operative second direction to disengage the second shaft portion from the first switch, thereby disengaging the motor.
In an embodiment, the method includes a step of displacing the knob in a predetermined direction along the first graduations to facilitate actuation of the motor at motor speeds corresponding to the first graduations.
The present invention also envisages a mixer grinder comprising a casing, a motor contained in the casing and a speed control unit provided in the casing. The speed control unit comprises a first switch configured to be in electrical communication with the motor. The speed control unit includes a second switch having a shaft defined by a first shaft portion configured to extend from an operative first surface of the second switch, and a second shaft portion configured to extend from an operative second surface of the second switch. The second shaft portion is configured to abut the first switch in an operative configuration of the control unit. The speed control unit further includes a housing configured to be located on the second switch, the housing having a set of first graduations corresponding to a set of motor speeds and at least one second graduations corresponding to a desired function marked thereon. The housing further having an aperture configured to receive the operative first shaft portion therein, and the knob rotatably provided on the housing. The knob is configured to abut the operative first shaft portion. The knob is configured to be pressed at the second graduation, in an operative first configuration of the control unit, to linearly displace the shaft to facilitate abutment of the second shaft portion with the first switch and actuate the motor at a speed corresponding to the desired function. The knob is further configured to be rotated along the set of first graduations, in an operative second configuration of the control unit, to facilitate actuation of the motor at the corresponding motor speeds.
In an embodiment, the housing of the mixer grinder includes an illuminating unit configured to be activated in an operative configuration of the speed control unit.
In another embodiment, the housing includes a failsafe unit configured to be connected to the motor. The failsafe unit is configured to be actuated in a defective configuration of the speed control unit.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A speed control unit, of the present disclosure, for a kitchen appliance will now be described with the help of the accompanying drawing, in which:
FIGURE 1 illustrates an exploded view of the speed control unit of the present disclosure;
FIGURE 2 illustrates an exploded view of a printed circuit board of Figure 1;
FIGURE 3A illustrates a front view of a knob showing selection of speed from the set of speed graduation at slow level;
FIGURE 3B illustrates a front view of a knob showing selection of speed from the set of speed graduation at 1st level;
FIGURE 3C illustrates a front view of a knob showing selection of speed from the set of speed graduation at 2nd level;
FIGURE 3D illustrates a front view of a knob showing selection of speed from the set of speed graduation at 3rd level; and
FIGURE 3E illustrates a front view of a knob showing selection of speed from the set of speed graduation at 0th level.
LIST OF REFERENCE NUMERALS
100 speed control unit
105 fasteners
110 printed circuit board
115 first switch
120 potentiometer
122 shaft
125 second switch
130 housing
135 aperture
140 recess
145 knob
150 first graduations
155 second graduations
DETAILED DESCRIPTION
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details, are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, elements and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawings.
A speed control unit, of the present disclosure, for a kitchen appliance will now be described in detail with reference to Figure 1 through Figure 3E. The kitchen appliance is provided with a motor.
Figure 1 illustrates an exploded view of the speed control unit of the present disclosure.
The speed control unit (100) comprises a first switch (115) (shown in Figure 2) configured to be in electrical communication with the motor. The speed control unit (100) further comprises a second switch (125) having a shaft (122) defined by a first shaft portion configured to extend from an operative first surface of the second switch (125), and a second shaft portion (not shown in figures) configured to extend from an operative second surface of the second switch (125). The second shaft portion of the second switch (125) is configured to abut the first switch (115) in an operative configuration of the control unit (100). The speed control unit (100) has a housing (130) configured to be located on the second switch (125) with the support of fasteners (105). The housing (130) has a set of first graduations (150) marked thereon corresponding to a set of motor speeds and at least one second graduation corresponding to a desired function marked thereon. The housing (130) further has an aperture (135) configured to receive the operative first portion of the second switch (125) therein. The speed control unit (100) has a rotary knob (145) rotatably provided on the housing (130). The knob (145) is configured to abut the operative first portion of the second switch (125).
The knob (145) is configured to be pressed at the second graduation (155), in an operative first configuration of the control unit (100), to linearly displace the shaft (122) facilitate abutment of the second shaft portion with the first switch (115) to actuate the motor at a speed corresponding to the desired function.
The knob (145) is further configured to be rotated along the set of first graduations (150), in an operative second configuration of the control unit (100), to facilitate actuation of the motor at the corresponding motor speeds.
In an embodiment, the speed control unit (100) includes a potentiometer (120) attached to the first switch (115). More specifically, the potentiometer (120) has a slot configured in an operative central portion thereof. The potentiometer (120) is configured to be attached on the PCB, such that the first switch (115), particularly the actuating component of the first switch (115) is received in the slot of the potentiometer. Such an arrangement allows the abutment of the second shaft portion of the second switch (122) with the first switch (115) when required. The potentiometer (120) is configured to be in electrical communication with the motor. The potentiometer (120) is configured to detect the angular displacement of the rotary knob (145), and is further configured to vary the voltage input to the motor based on the sensed angular displacement, to run the motor at the desired motor speed.
In an embodiment, the knob (145) is configured to be locked at the second graduation (155) to prevent angular displacement of the knob (145) in the operative first configuration of the motor at the second graduation (155). In another embodiment, the speed control unit (100) includes a locking plate (not particularly shown in figures) configured to be disposed below the housing (130), above the second switch (125) and the first switch (115). In an embodiment, the locking plate is fastened to the PCB and the housing (130). A hole is configured on the locking plate for receiving the first shaft portion therein, and to allow the first shaft portion to pass therethrough. In still another embodiment, the locking plate further includes a rib configured thereon. A plurality of slots (not shown in figures) is configured on the rib at a space apart distance therebetween.
In yet another embodiment, the second switch (125) includes a plurality of teeth (not shown in figures) configured thereon. In an embodiment, the second switch (125) is placed in the unit (100) such that a space apart distance is defined between the rib and the locking plate, in a non-operative configuration of the speed control unit or is in its operative second configuration.
The teeth are configured to be received in the slots, in the operative first configuration of the speed control unit (100). More specifically, when the knob (145) is pressed down, the teeth of the second switch (125) are linearly displaced towards the locking plate along with the second switch (125), and are lockably received in the slots to restrict any movement of the second switch, thus allowing only linear displacement of the knob in the operative first configuration, but preventing displacement of the knob (145) in the angular direction.
Conversely, in the operative second configuration of the speed control unit (100), the teeth are configured to be angularly displaced along with the second switch (125), and are not received in the slots.
In an embodiment, the shaft (122) is a spring-loaded shaft configured to facilitate displacement of the first switch (115) to its original position, thereby disengaging the motor.
In an embodiment, a printed circuit board (PCB) (110) is fastened to the motor with the help of fasteners (105). In another embodiment, the length of the first portion of the shaft is more than the length of the second portion of the shaft in the second switch (125).
In an embodiment, the recess (140) is configured on an operative outer surface of the housing (130) to facilitate nesting of the knob (145) on the housing (130).
In an embodiment, the second graduation (155) includes the desired function which is selected from a group consisting of the pulse function, whip function, blend function, coarse function, boost function, chop function or any other functionality in the kitchen appliance.
In an embodiment, the first switch (115) is a tactile switch configured to be soldered to the PCB.
In another embodiment, the second switch (125) is a cam switch.
Referring to Figure 2, the printed circuit board (110) being configured to facilitate mounting of the first switch (115) thereon.
In an embodiment, as shown in Figures 3A, 3B, 3C, 3D and 3E, the set of first graduations correspond to 0th level, slow level, 1st level, 2nd level and 3rd level of speed. Figure 3A illustrates a front view of a knob showing the set of first speed graduation at a slow level. Figure 3B illustrates a front view of a knob showing the set of first speed graduation at 1st level. Figure 3C illustrates a front view of a knob showing the set of first speed graduation at 2nd level. Figure 3D illustrates a front view of a knob showing the set of first speed graduation at 3rd level, and Figure 3E illustrates a front view of a knob showing the set of first speed graduation at 0th level.
In an embodiment, 0th is the level at which the motor is deactivated and 3rd level is the highest speed level.
The speed control unit, of the present disclosure, can be used in a kitchen appliance including coffee grinders, food processors, spice mixers and any other kitchen appliance having speed control mechanisms.
The present disclosure further envisages a method for operating the speed control unit of the present disclosure. The method comprises the following steps:
• locating the knob (145) at the second graduation (155);
• pressing the knob (145) in an operative downward direction at the second graduation (155) to enable linear displacement of the shaft (122) in an operative first direction to facilitate abutment of the second shaft portion with the first switch (115) to actuate the motor at a speed corresponding to the desired function; and
• releasing the knob (145) to enable linear displacement of the shaft (122) in an operative second direction to disengage the second shaft portion from the first switch (115), thereby disengaging the motor.
In an embodiment, the method includes a step of angularly displacing the knob (145) in a predetermined direction along the first graduations (150) to facilitate actuation of the motor at motor speeds corresponding to the first graduations (150).
The present invention also envisages a mixer grinder comprising a casing, a motor contained in the casing and a speed control unit provided in the casing. The speed control unit (100) comprises a first switch (115) configured to be in electrical communication with the motor. The speed control unit includes a second switch (125) having a shaft defined by a first shaft portion configured to extend from an operative first surface of the second switch (125), and a second shaft portion configured to extend from an operative second surface of the second switch (125). The second shaft portion is configured to abut the first switch (115) in an operative configuration of the control unit. The speed control unit (100) further includes a housing (130) configured to be located on the second switch (125), the housing (130) having a set of first graduations (150) corresponding to a set of motor speeds and at least one second graduations (155) corresponding to a desired function marked thereon. The housing (130) further has an aperture (135) configured to receive the operative first shaft portion therein, and the knob (145) rotatably provided on the housing (130). The knob (145) is configured to abut the operative first shaft portion.
The knob (145) is configured to be pressed at the second graduation (155), in an operative first configuration of the control unit (100), to linearly displace the shaft (122) facilitate abutment of the second shaft portion with the first switch (115) to actuate the motor at a speed corresponding to the desired function.
The knob (145) is further configured to be rotated along the set of first graduations (150), in an operative second configuration of the control unit (100), to facilitate actuation of the motor at the corresponding motor speeds.
In an embodiment, the housing (130) of the mixer grinder includes an illuminating unit configured to be activated in an operative configuration of the speed control unit (100).
In another embodiment, the housing (130) includes a failsafe unit configured to be connected to the motor. The failsafe unit is configured to be actuated in a defective configuration of the speed control unit (100).
In an operative configuration, the speed control unit (100) is used in a mixer grinder, wherein the knob (145) is pressed in an operative linear direction through the second graduations (155) by an operator. The pressing action linearly displaces the spring-loaded shaft (122) of the second switch (125) to engage the first switch (115), and causes the end of the operative second portion of the shaft (122) to abut the first switch (115) which completes the electric circuit to activate the motor at a speed corresponding to the desired function. The knob (145) is configured to be locked at the second graduation (155) to prevent angular displacement of the knob (145) in an operative configuration of the motor at the second graduation (155). The operator releases the pressing action of the knob (145), thereby enabling the spring-loaded shaft (122) to facilitate displacement of the first switch (115) to its original position, thereby disengaging the motor and deactivating the desired function.
Further, the knob (145) is then angularly displaced from 0th level to the desired level in a predetermined direction. The potentiometer (120) is configured to detect the angular displacement of the rotary knob (145), and is further configured to vary the voltage input to the motor based on the sensed angular displacement, to run the motor at the desired motor speed. For example- the user presses and angularly displaces the knob (145) from 0th level to 1st speed level. This angular displacement of the knob (145) is sensed by the potentiometer (120) which varies the voltage input to the motor from 0 RMS to a predetermined voltage value assigned for the 1st speed level to run the motor at the desired motor speed. Similarly, the potentiometer (120) varies the voltage input to the motor when the knob (145) is angularly displaced from 0 to slow, from slow to 1, from 1 to 2, from 2 to 3, and back from 3 to 2, from 2 to 1, from 1 to slow, and from slow to 0.
In an embodiment, the knob (145) has to be angularly displaced to 0th level or any predetermined graduation before implementing the desired function.
In an embodiment, the knob (145) can be angularly displaced directly from 0th speed level to the 3rd speed level in one smooth fluidic motion.
In an embodiment, the set of first graduations (150) and second graduation (155) can be provided on the knob (145) of the speed control unit (100).The first switch (115) and the potentiometer (120) enable smooth motion of the knob (145) without making any noises. The speed control unit (100), of the present disclosure, not only has a reliable configuration but is also easy to use. Further, absence of rubber gaskets and spring elements (as was used in conventional speed control units) reduces the effect of continuous vibrations on the speed control unit (100), and improves the durability and life of the speed control unit (100).
The pressing mechanism of the knob (145) of the present disclosure ensures that there is no abrupt change in the speed of the motor for the desired function mode thereby providing complete protection to the motor assembly.
The envisaged speed control unit (100) has a simple yet cost-effective configuration with relatively improved sensibility. Further, the speed control unit can be used conveniently and with ease.
The foregoing description of the embodiments has been provided for purposes of illustration and is not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
TECHNICAL ADVANCEMENTS
The present disclosure described hereinabove has several technical advantages including, but not limited to, the realization of a speed control unit for a mixer grinder that:
• has a simple yet cost-effective configuration;
• has relatively improved sensibility; and
• can be used conveniently and with ease;
The aspect herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation. ,CLAIMS:WE CLAIM:
1. A speed control unit (100) for a kitchen appliance having a motor, said speed control unit comprising:
• a first switch (115) configured to be in electrical communication with the motor;
• a second switch (125) having a shaft (122) defined by a first shaft portion extending from an operative first surface of said second switch (125), and a second shaft portion extending from an operative second surface of said second switch (125), said second shaft portion configured to abut said first switch (115) in an operative configuration of said control unit;
• a housing (130) configured to be located on said second switch (125), said housing (130) having a set of first graduations (150) corresponding to a set of motor speeds and at least one second graduations (155) corresponding to a desired function marked thereon, said housing (130) further having an aperture (135) configured to receive said operative first shaft portion therein; and
• a knob (145) rotatably provided on said housing (130), said knob configured to abut said operative first shaft portion, said knob (145) configured to be pressed at said second graduation, in an operative first configuration of said control unit (100), to linearly displace said shaft (122) to facilitate abutment of said second shaft portion with said first switch (115) and actuate the motor at a speed corresponding to said desired function, said knob (145) further configured to be rotated along said set of first graduations (150), in an operative second configuration of said control unit (100), to facilitate actuation of the motor at said corresponding motor speeds.
2. The speed control unit (100) as claimed in claim 1, which includes a potentiometer (120) attached to said first switch (115), said potentiometer (120) being configured to be in electrical communication with the motor, said potentiometer (120) is configured to detect the angular displacement of said rotary knob (145), and is further configured to vary the voltage input to the motor based on said sensed angular displacement, to run the motor at the desired motor speed.
3. The speed control unit (100) as claimed in claim 1, wherein said knob (145) is configured to be locked at said second graduation to prevent angular displacement of said knob (145) in an operative configuration of the motor at said second graduation.
4. The speed control unit (100) as claimed in claim 1, wherein said shaft (122) is a spring-loaded shaft configured to facilitate displacement of said first switch (115) to its original position, thereby disengaging the motor.
5. The speed control unit (100) as claimed in claim 1, wherein the desired function is selected from a group consisting of pulse function, whip function, blend function, coarse function, boost function, chop function or any other functionality in the kitchen appliance.
6. The speed control unit (100) as claimed in claim 1, wherein the first switch (115) is a tactile switch.
7. The speed control unit (100) as claimed in claim 1, wherein the second switch (125) is a cam switch.
8. The speed control unit (100) as claimed in claim 1, wherein a printed circuit board (110) is fastened to the motor, said printed circuit board (110) being configured to facilitate mounting of said first switch (115) thereon.
9. The speed control unit (100) as claimed in claim 1, wherein the set of first graduations (150) includes 0th speed level, slow speed level, 1st speed level, 2nd speed level and 3rd speed level, said 0th speed level being the level at which the motor is deactivated and 3rd speed level being the highest speed level.
10. The speed control unit (100) as claimed in claim 9, wherein the potentiometer (120) is configured to increase the voltage input to the motor when the knob (145) is angularly displaced from 0th to slow, from slow to 1st level, from 1st level to 2nd level, from 2nd level to 3rd level, and is further configured to decrease the voltage input from 3rd level to 2nd level, 2nd level to 1st level, 1st level to slow level and from slow level to 0th level.
11. The speed control unit (100) as claimed in claim 1, wherein the length of said first portion of said shaft (122) is more than the length of said second portion of said shaft (122).
12. The speed control unit (100) as claimed in claim 1, wherein said housing (130) includes a recess (140) configured on an operative outer surface thereof to facilitate nesting of said knob (145) on said housing (130).
13. A method for operating said speed control unit as claimed in claim 1, said method comprising the following steps:
• locating said knob (145) at said second graduation (155);
• pressing said knob (145) in an operative downward direction at said second graduation (155) to enable linear displacement of said shaft (122) in an operative first direction to facilitate abutment of said second shaft portion with said first switch (115) to actuate the motor at a speed corresponding to said desired function; and
• releasing said knob (145) to enable linear displacement of said shaft (122) in an operative second direction to disengage said second shaft portion from said first switch (115), thereby disengaging the motor.
14. The method as claimed in claim 13, which includes the step of angularly displacing said knob (145) in a predetermined direction along said first graduations (150) to facilitate actuation of the motor at motor speeds corresponding to said first graduations (150).
15. A mixer grinder comprising:
• a casing;
• a motor contained in said casing;
• a speed control unit (100) provided in said casing, said speed control unit (100) comprising:
o a first switch (115) configured to be in electrical communication with said motor;
o a second switch (125) having a shaft (122) defined by a first shaft portion configured to extend from an operative first surface of said second switch (125), and a second shaft portion configured to extend from an operative second surface of said second switch (125), said second shaft portion configured to abut said first switch (115) in an operative configuration of said control unit;
o a housing (130) configured to be located on said second switch (125), said housing (130) having a set of first graduations (150) corresponding to a set of motor speeds and at least one second graduation corresponding to a desired function marked thereon, said housing (130) further having an aperture (135) configured to receive said operative first shaft portion therein; and
o a knob (145) rotatably provided on said housing (130), said knob configured to abut said operative first shaft portion, said knob (145) configured to be pressed at said second graduation, in an operative first configuration of said control unit (100), to linearly displace said shaft (122) to facilitate abutment of said second shaft portion with said first switch (115) to actuate the motor at a speed corresponding to said desired function, said knob (145) further configured to be rotated along said set of first graduations (150), in an operative second configuration of said control unit (100), to facilitate actuation of the motor at said corresponding motor speeds.
16. The mixer grinder as claimed in claim 15, wherein said housing (130) includes an illuminating unit configured to be activated in an operative configuration of said speed control unit (100).
17. The mixer grinder as claimed in claim 15, wherein said housing (130) includes a failsafe unit configured to be connected to the motor, said failsafe unit being configured to be actuated in a defective configuration of said speed control unit (100).
Dated this 16th day of February, 2024

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
of R.K.DEWAN & CO.
Authorized Agent of Applicant

TO,
THE CONTROLLER OF PATENTS
THE PATENT OFFICE, AT MUMBAI