FIELD
The present disclosure relates to the field of grinding machines.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
A cylindrical grinding machine is used for finishing the surface of a workpiece object using a grinding tool. The workpiece most likely has an axis of rotation. Machine components such as a pinion shaft, a camshaft or any such component with an axis of rotation are machined to precise diameters using cylindrical grinding machines. There is relative rotation between the workpiece and the grinding tool fitted on a grinding wheel, and the grinding wheel is fed into the workpiece in a direction perpendicular to the axis of rotation of the workpiece as the relative rotation takes place. Also, there can be relative translation between the workpiece and the grinding wheel parallel to the axis of rotation of the workpiece. The desired depth of material removal can be set before a numerically-controlled automatic cycle of automatic operation of the machine is initiated. The operator needs to manually operate a lever termed as a ‘feed lock lever’ to restrict the feed of the grinding wheel.
If the operator misses out on operating the feed lock lever before starting the automatic cycle of a conventional grinding machine, the grinding wheel would go into a continuous feed mode, thus removing excessive material from the workpiece. Such a workpiece gets rejected. Such a mistake on part of the operator leads to loss of workpiece material, a high setup time and decrease in productivity.
There is, therefore, need for a system which eliminates workpiece rejection due to human error in operation of a cylindrical grinding machine.
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 system for detecting missed operation of a feed lock lever in an automated cylindrical grinding machine.
Another object of the present disclosure is to provide a system which is accurate.
Yet another object of the present disclosure is to provide a system which is cost-efficient.
Still another object of the present disclosure is to provide a systemwhich can be retrofitted in an existing automated cylindrical grinding machine.
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 system for preventing excessive material removal from a workpiece in an automated grinding machine. The system comprises a manually operable lever, a sensor and a control unit. The lever is configured to limit translational motion of a grinding wheel of the automated grinding machine in a direction perpendicular to axis of rotation of the workpiece upto a predetermined extent when the lever is operated. The sensor senses a predetermined position of the lever. The sensor generates a position signal upon sensing the lever in the predetermined position. The control unit is configured to cooperate with the sensor. The control unit is further configured to allow initiation of an operation of the grinding machine when the position signal is received and prevent operation of the grinding machine when the position signal is absent.
In an embodiment, in the absence of said position signal, said control unit prevents at least one of the following operations:
a. rotation of the workpiece holding mechanism of the grinding machine;
b. displacement of the grinding wheel;
c. rotation of the grinding wheel; and
d. activation of the coolant pumping system of the grinding machine.
In an embodiment, the sensor is a proximity sensor. In another embodiment, the sensor is an optical sensor.
In an embodiment, in the absence of the position signal, the control unit is configured to trigger an audible alarm. In another embodiment, in the absence of the position signal the control unit triggers a visual alarm.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
A system for preventing excessive material removal from a workpiece in an automated grinding machine of the present disclosure will now be described with the help of the accompanying drawing, in which:
Figure 1 illustrates a schematic block diagram of an automated cylindrical grinding machine comprising a system of the present disclosure; and
Figure 2 is a flowchart of the working of a system for preventing excessive material removal from a workpiece in an automated grinding machine of the present disclosure.
LIST OF REFERENCE NUMERALS
100 Automated cylindrical grinding machine
10 Workpiece holding mechanism
20 Grinding wheel
30 Coolant supply system
40 Control unit
50 Feed lock lever
60 Sensor

DETAILED DESCRIPTION
Embodiments, of the present disclosure, will now be described with reference to the accompanying drawing.
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 “comprises”, “comprising”, “including” and “having” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present disclosure is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
An automated cylindrical grinding machine 100 comprises a workpiece holding mechanism 10, a grinding wheel 20, a coolant supply system 30 and a control unit 40. The workpiece holding mechanism 10 holds a workpiece as well as rotates the workpiece about an axis. The grinding wheel 20 has an abrasive-coated cylindrical surface. The grinding wheel 20 rotates parallel to the axis of rotation of the workpiece as well as is ‘fed’ into the workpiece by displacing relative to the workpiece in a direction perpendicular to axis of rotation of the workpiece. The coolant supply system 30 comprises a pump, a pipe and a reservoir of a coolant. The pump pumps the coolant from the reservoir and feeds the coolant through the pipe over the workpiece. The control unit 40 controls displacement of the workpiece holding mechanism 10 and the grinding wheel 20 and activation of the coolant supply system 30, once the automatic cycle is switched ON by the operator.
The conventional automated cylindrical grinding machine 100 is provided with a manually operable feed lock lever 50, wherein upon operation of the lever 50, feed of the grinding wheel 20 is limited upto a predetermined radial distance within the workpiece. If the operator forgets to turn the feed lock lever 50 after initiating the automatic grinding cycle, a continuous feed of the grinding machine 100 ensues in a conventional automated grinding machine. Due to excessive material removal, the workpiece gets rejected, leading to loss in productivity and efficiency of the grinding operation in general. There is a need for eliminating part rejection due to human error in operation of a cylindrical grinding machine 100.
The present disclosure provides a system which makes the operator of a cylindrical grinding machine alert in case the operator forgets turning the feed lock lever 50. This is achieved by introducing a sensor 50 in the control unit 40 of an existing cylindrical grinding machine 100, as illustrated in the schematic block diagram of Figure 1. The sensor 50 senses the feed lock lever 50 in an operative (ON) state and generates an electronic signal. In the absence of the signal generated by the sensor 50, the control unit 40 of the grinding machine 100, which controls the operation of the cylindrical grinding machine 100 in the automatic grinding cycle, prevents activation of at least one of: (a) rotation of the workpiece holding mechanism 10; (b) displacement of the grinding wheel 20; (c) rotation of the grinding wheel 20; and (d) the coolant supply system 30. Thus, the operator is prompted to notice that, despite turning the automatic cycle ON, the workpiece holding mechanism 10 is not turning or the grinding wheel 20 is not rotating or moving in towards the workpiece or the coolant is not being supplied. Hence, the operator promptly checks for state of the feed lock lever 50 and hence turns the same in an operative state. The sensor 50 senses an operative (ON) position of the feed lock lever 50 and generates a signal which is transmitted to the control unit 40. Thereafter, the control unit 40 initiates the automatic grinding cycle of the machine, which proceeds as per instructions stored in the repository 50 by the control unit 40. Feed of the grinding wheel 20 is provided upto the distance specified by the operator and hence, component rejection due to excessive material removal from the workpiece as a result of continuous feed of the grinding wheel 20 is prevented. The working of the automated cylindrical grinding machine 100 as described hereinabove is illustrated in the flowchart of Figure 2.
In an embodiment, the sensor 50 for sensing the ON position of the feed lock lever 50 is a proximity sensor. In another embodiment, the sensor 50 is an optical sensor.
In an embodiment, the control unit 40 also generates an audio signal. For this purpose, an electrically-driven horn is coupled to the control unit 40. In another embodiment, the control unit 40 also generates a visual signal. For this purpose, an electrically-driven visual indicator such as a blinker light bulb or tube is coupled to the control unit 40.
When an element is referred to as being “mounted on”, “engaged to”, “connected to” or “coupled to” another element, it may be directly on, engaged, connected or coupled to the other element. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed elements.
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.
Terms such as “inner”, “outer”, “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used in the present disclosure to describe relationships between different elements as depicted from the figures.
The foregoing description of the embodiments has been provided for purposes of illustration and 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 herein above has several technical advantages including, but not limited to, the realization of a system for preventing excessive material removal from a workpiece in an automated grinding machine, which:
• is easy to operate;
• eliminates component rejection due to human error; and
• can be implemented on an existing automated grinding machine.
The foregoing disclosure has been described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.
The embodiments 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 documents, acts, materials, 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.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
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 system for preventing excessive material removal from a workpiece in an automated grinding machine (100), said system comprising:
• a manually operable lever (50), said lever configured to limit translational motion of a grinding wheel (20) of said automated grinding machine (100) in a direction perpendicular to axis of rotation of the workpiece upto a predetermined extent when said lever (50) is operated;
• a sensor (50) for sensing a predetermined position of said lever (50), wherein said sensor (50) generates a position signal upon sensing said lever (50) in said predetermined position; and
• a control unit (40) configured to cooperate with said sensor (50), said control unit (40) further configured to allow initiation of an operation of said grinding machine (100) when said position signal is received and prevent an operation of said grinding machine (100) when said position signal is absent.
2. The system as claimed in claim 1, wherein, in the absence of said position signal, said control unit (40) prevents at least one of the following operations:
a. rotation of a workpiece holding mechanism (10) of said grinding machine (100);
b. displacement of said grinding wheel (20);
c. rotation of said grinding wheel (20); and
d. activation of the coolant pumping system (30) of said grinding machine (100).
3. The system as claimed in claim 1, wherein said sensor (50) is a proximity sensor.
4. The system as claimed in claim 1, wherein said sensor (50) is an optical sensor.
5. The system as claimed in claim 1, wherein, in the absence of said position signal, said control unit (40) is configured to trigger an audible alarm.
6. The system as claimed in claim 1, wherein, in the absence of said position signal, said control unit (40) is configured to trigger a visual alarm.