What is claimed is:
1. An automatic vending machine comprising:
a commodity storage for storing a number of items to be sold;
a refrigerating circuit having a cooling unit connected to said commodity storage for cooling said items;
a defrosting unit connected to said cooling unit for intermittently carrying out a defrosting operation for said cooling unit;
a temperature sensor connected to said commodity storage for detecting a storage temperature within said commodity storage to produce a temperature signal;
a calculating unit connected to said temperature sensor and responsive to said temperature signal for calculating a temperature variation rate prior to said defrosting operation; and
a defrost control part connected to said calculating unit and said defrosting unit for controlling said defrosting operation with reference to said temperature variation rate.
2. An automatic vending machine as claimed in claim 1, further comprising:
an operation limiting part connected to said refrigerating circuit for limiting a predetermined operation of said automatic vending machine; and
a limitation canceling part connected to said calculating unit and said operation limiting part for canceling a limitation of said predetermined operation when said temperature variation rate is not smaller than a predetermined rate.
3. An automatic vending machine as claimed in claim 1, wherein said defrosting unit carries out said defrosting operation at a preselected time interval for a preselected time period, said defrost limiting part controlling said predetermined time period.
4. An automatic vending machine as claimed in claim 3, further comprising a suspension time setting part connected to said defrosting unit for setting said preselected time interval.
5. An automatic vending machine as claimed in claim 1, wherein said calculating unit comprises:
a first calculating part connected to said temperature sensor and responsive to said temperature signal for calculating a predetermined number of variation rates of temperature per unit time; and
a second calculating part connected to said first calculating part and said defrost control part for calculating an average value of said variation rates to supply said average value as said temperature variation rate to said defrost control part.
6. An automatic vending machine as claimed in claim 5, further comprising a unit time setting part connected to said first calculating part for setting said unit time.
7. An automatic vending machine as claimed in claim 6, further comprising a number setting part for setting said predetermined number.
8. An automatic vending machine as claimed in claim 1, wherein said defrost control part comprises:
a comparing part connected to said calculating unit for carrying out a comparison operation between said temperature variation rate with a reference value; and
a local control part connected to said comparing part and said defrosting unit for controlling an operation of said defrosting unit in response to a result of said comparison operation.
9. An automatic vending machine as claimed in claim 8, further comprising a reference value setting part connected to said defrost control part for setting said reference value to supply said reference value to said defrost control part.
10. An automatic vending machine as claimed in claim 8, further comprising a local calculating part connected to said defrost control part for calculating said reference value based on predetermined conditions related to said commodity storage to supply said reference value to said defrost control part.
11. An automatic vending machine as claimed in claim 8, further comprising:
a desired value setting part for setting a desired value related to said temperature variation rate;
a value calculating part for calculating a calculated value based on predetermined conditions related to said commodity storage; and
a value selecting part connected to said desired value setting part, said value calculating part, and said defrost control part for selecting, as said reference value, one of said desired and said calculated values to supply said reference value to said defrost control part.
12. An automatic vending machine as claimed in claim 1, further comprising a cooling control part connected to said refrigerating circuit and said calculating unit for controlling an operation of said refrigerating circuit in response to said temperature variation rate.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. Apparatus for making a specific shaped hollow (10) in a work piece (11), comprising
a laser machining apparatus (12-18) which is configured to, in a layer-wise manner, remove material of a work piece (11) in horizontal layers (S; xy) corresponding to the specific shape, and
a measurement apparatus (70-73) which is configured to continuously measure the depth (z) of the hollow,
characterized by a control apparatus (81) which is configured to determine the boundaries (xg, yg) in horizontal direction for removal in a subsequent layer (Si+1) in accordance with the depth (z) of the hollow from the form definition.
2. Apparatus according to claim 1, characterized in that the control apparatus comprises a determining means (82) for determining the thickness (Dz) of a removed layer (Sl) from the measured depth of the hollow, and the control apparatus (81) determines the boundaries (xg, Yg) in horizontal direction for removal in a subsequent layer (Si+1) also in accordance with the determined layer thickness (Dz).
3. Apparatus according to claim 1, characterized by a memory (83) for storing the form definition of the hollow (10).
4. Apparatus for making a specifically shaped hollow (10) in a work piece (11), comprising
a laser machining apparatus (12-18), which is configured to, in a layer-wise manner, remove material from the work piece (11) corresponding to the specific shape, and a measurement apparatus which is configured to continuously measure the depth (z) of the hollow,
characterized by a memory means (91) which is configured to continuously store the measurement values together with the respective coordinates or at memory locations corresponding to the respective coordinates, and
a control apparatus (63, 92, 93) which is configured to control the laser machining apparatus (12-18) in accordance with the stored measurement values.
5. Apparatus according to claim 4, characterized in that the control apparatus uses a stored measurement value if within the same layer the laser beam is close by a site corresponding to said measurement value, andor if, in a deeper layer, the laser is close by or at a site corresponding to the measurement value.
6. Apparatus according to claim 4, characterized in that the control apparatus uses a measurement value for the instantaneous or later adjustment of the interaction parameters of the laser beam.
7. Apparatus according to claim 1, the laser machining apparatus (12-18) guiding, by means of a laser beam guidance, the laser light across the surface of a work piece within a working area defined by the apparatus, comprising
a depth sensor (70, 71) which uses for depth measurement light emanating from the working site and generates a measurement value,
characterized by a calibrating apparatus (72-74) adapted to measure a preferably flat calibrating surface and having a memory (73) for storing correction values in accordance with differences between measurement values and known values together with the respective coordinates or at memory locations corresponding to the respective coordinates, and
a correction apparatus (74, 75) which corrects the measurement value in accordance with the position of the site with reference to the correction values stored in said memory (74).
8. Apparatus according to claim 7, characterized in that the correction is made by adding a value andor by multiplying a value.
9. Apparatus according to claim 7, characterized in accordance with the depth of the hollow.