Patent Application
20070142959
This application relates generally to food product slicers used for slicing bulk food products and, more specifically, to a food product slicer including a control for determining when to sharpen the slicer knife.
Food product slicers having circular slicer knives are commonly used in restaurant and grocery businesses, among others. The use of slicer mounted knife sharpening assemblies to sharpen the peripheral edge of the slicer knife when necessary is also known. Many operators have difficulty determining when the slicer knife needs to be sharpened. The nature and extent of use of the slicer can vary widely, making the determination even more difficult. It would be desirable to provide a food product slicer that incorporates a feature that automatically identifies when the slicer knife should be sharpened.
In one aspect, a food product slicer includes a slicer body and a slicer knife mounted for rotation relative to the slicer body. The slicer knife has a peripheral cutting edge. A food product carriage is mounted to the slicer body for reciprocating movement back and forth past a cutting zone of the slicer knife. A control is operable to track a count of a selected knife use characteristic of the slicer. The control is operable to effect production of a knife sharpen signal based at least in part upon the count.
In another aspect, a method is provided for identifying when to sharpen a circular slicer knife of a slicer having a food product carriage mounted for reciprocating movement back and forth past a cutting zone of the slicer knife. The method includes the steps of: tracking a count of a selected knife use characteristic of the slicer; comparing the tracked count with a set count; and producing a knife sharpen signal based at least in part upon the comparison.
Referring to
The illustrated cover plate 20 covers the peripheral cutting edge 24 of the slicer knife 14 from about a one o'clock position 32 to about a seven o'clock position 34. The peripheral cutting edge 24 is shown in shadow beneath the cover plate 20. In a twelve o'clock region 36 of the slicer knife 14, the cover plate diameter decreases to provide a space or opening at which the edge of knife can be sharpened. The cover plate 20 also extends over a ring guard 38 (only inner edge shown in shadow in
The configuration of the sharpening assembly 42 provided in connection with a given slicer can vary widely. Referring now to
In one embodiment, an actuating handle or lever (not shown) may be provided for contacting the rear side 188 of the block member 152 to push the block member toward the knife 14 and move the sharpening wheel 168 from its standby position, which is the position shown in
Referring to
Referring to
In one technique, the controller 402 tracks a count of slicing strokes of the food product carriage 18, based upon the feedback from sensor 418, in order to determine when to sharpen the knife. Specifically, based upon knife testing it can be determined that, on average, a slicer knife needs to be sharpened after a given number of slicing strokes. The controller tracks the count of slicing strokes and when the count exceeds the given number, the controller outputs a knife sharpen signal (e.g., causing a buzzer or other audio annunciator 422 to output a sound, causing an LED or other visual annunciator 424 to output a visual signal and/or causing a sharpen message to be displayed on the display 410). Where the sharpener is manual, the slicer operator can then initiate a manual sharpening operation and actuate the user input 412 to reset the slicing stroke count once sharpening is completed. Alternatively, a sharpen sensor 426 could be mounted on the sharpener 42 to trigger a feedback to the controller 402 upon sharpening (e.g., after the sharpening wheel 168 has been fully extended for some minimum period of time).
Where the sharpener is automated (as by solenoid 340), the knife sharpen signal could cause sharpening to take place automatically, without requiring operator input. For example, the controller 402 could automatically initiate sharpening after the slicing stroke count reaches the given number, provided the slicer is not in use (e.g., after the slicer knife and carriage have been stopped for a set time period). Alternatively, the operator may be required to trigger automated sharpening via actuation of the user input 412, which could simultaneously serve to reset the count.
In one implementation of the slicing stroke counting technique, the slicing strokes are only counted when the knife is running (e.g., as determined by the motor 406 being energized or based upon the feedback from encoder 414 or sensor 416). In another implementation of the slicing stroke counting technique, the slicing strokes are only counted when the knife is running and when a load on the knife driver exceeds a threshold level (e.g., as determined by the feedback from load sensor 420). In yet another implementation of the slicing stroke counting technique, multiple slicing stroke counts can be tracked according to food product sliced. An algorithm may be used to evaluate the multiple counts in a cumulative manner, with the algorithm taking into account the impact the type of food product has on dulling of the knife (e.g., it takes less slicing strokes of cheese to dull the knife when compared to turkey slicing strokes). In the latter implementation, the user input 412 can be utilized by the operator to input the type of food product being sliced (as by entering a product look-up (PLU) number). Alternatively, the slicer may include RFID capabilities as described in the PCT application published under International Publication No. WO 2005/004071 A1, by which the slicer can automatically determine the product being sliced based upon a sensed RFID tag of the food product.
In another technique, the controller 402 may count rotations of the slicer knife 14 (as determined by feedback from encoder 414 and/or sensor 416, or as determined by assuming a certain running speed for the knife, tracking knife on time and calculating knife rotations) in order to determine when to sharpen the knife. Specifically, based upon knife testing it can be determined that, on average, a slicer knife needs to be sharpened after a given number of knife rotations takes place. The controller tracks the count of knife rotations and when the count exceeds the given number, the controller outputs the knife sharpen signal. In one implementation of the knife rotation counting technique, knife rotations are only counted when a load on the knife driver exceeds a threshold level (e.g., as determined by the feedback from load sensor 420). In another implementation of the knife rotation counting technique, knife rotations are only counted when the food product carriage is moving (as determined by the feedback from sensor 418 or by energization of motor 408; where sensor 418 is an end of stroke sensor switch, the carriage may be considered to be “moving” (as that term is used herein) provided the sensor 418 is repeatedly tripped within a set time period, such as being tripped every 3-6 seconds for example).
In yet another technique, the controller 402 may count the running time of the slicer knife (as determined by the knife motor 406 being energized or ad determined by feedback from encoder 414 and/or sensor 416) in order to determine when to sharpen the knife. Specifically, based upon knife testing it can be determined that, on average, a slicer knife needs to be sharpened after running for a certain period of time. The controller tracks a time count corresponding to knife running time and when the count exceeds the given number, the controller outputs the knife sharpen signal. In one implementation of the knife running time counting technique, the run time is only counted when the food product carriage is moving (as determined by feedback from sensor 418 or by energization of motor 408).
In determining whether the count for the selected knife use characteristic exceeds a set count, the count could be a count up from zero to the set count (in which case count reset is back to zero) or the count could be a count down from the set count to zero (in which case count reset is back to the set count).
In tracking the count of the selected knife use characteristic, in one embodiment the controller may actually maintain a digital count value in memory, with the value being incremented or decremented as the case may be. Other types of digital counter implementations could also be used. In another embodiment the controller may include an analogue counter, such as one in which voltage pulses (e.g., one pulse corresponding to one count) are input to an integrator. When the voltage output of the integrator reaches a specific voltage, the set count is considered to be reached Other types of analogue counters could also be used. Accordingly, as used herein, it is not necessary for a digital number to be stored and incremented/decremented in order for an apparatus to fall within the scope of the meaning of the term “track a count” or “tracking a count” as used in the claims.
It is to be clearly understood that the above description is intended by way of illustration and example only, is not intended to be taken by way of limitation, and that other changes and modifications are possible.
