AUTOROTATING METAL DETECTOR INSTALLATION STRUCTURETECHNICAL FIELDThe present invention relates to a metal detection machine, and in particular, to an autorotating metal detector installation structure which is applied for metal detection of a product which requires consistent detection of metal objects with high directivity.
BACKGROUNDCurrently, a metal detector in industrial application is a precision detecting device for excluding the contamination of foreign metal inclusions. The metal detector is typically employed for detecting the foreign metal inclusions within food, medicines, cosmetics, fabrics, or the like, which are mixed therein during manufacture. The operating principle thereof is that the metal detector includes a central transmitter coil and two counter receiver coils, and these coils are assembled in one probe. An oscillator transmits a high-frequency magnetic field via the central transmitter coil. The two receiver coils are connected but of opposite polarities, such that the output voltage signals produced by them can be mutually counteracted when the magnetic field is not subjected to external interference. Once metal impurities come into the filed, this balance will be broken, and the induction voltage of the two receiver coils cannot be counteracted completely, thus the un-counteracted induction voltage is magnified by a control system, such that the metal detector can detect the presence of metal and produces alarm signals (metal impurities are detected) . Then the system can utilize the alarm signals to drive an auto rejecting means, so as to exclude the metal impurities out of the production line.
However, in the field of metal detection, the directivity of the metals within products often restricts the reliability of the detection. Due to the high requirements on the directivity of the metals in products, the detecting precision of the metal detector may be limited. If only one metal detector is used for detecting the product with high requirement on directivity thereof, then it is difficult to obtain high precision on the detection.
With respect to the prior metal detection machines, when detecting a product with high requirements on the directivity, for achieving high precision, it is necessary to apply two metal detectors simultaneously and they should be arranged in an angle therebetween on a frame, meanwhile, the total length of the conveyor has to be increased. However, it is expensive to configure a metal detection machine with two metal detectors, thus it costs too much to achieve highly precise detection for the aforementioned products.
SUMMARY
In light of the disadvantages in the prior art, the objective of the present invention is to provide an autorotating metal detector installation structure, which is used for high-precision detection of the products with high requirements on metal directivity.
To achieve the objective as mentioned above, the present invention provides an autorotating metal detector installation structure, characterized in that it comprises:
a frame with at least one guiding element wherein the at least one guiding element has the shape of a circular arc;
at least three supporting elements connected with the metal detector, wherein the at least three supporting elements are supporting the metal detector and wherein each of the at least three supporting elements comprises a gliding element at its lower end that is resting on the frame and that allows the metal detector to be moved smoothly on the frame;
at least one guided element that is connected to the metal detector and that is connected in tangential contact with the at least one guiding element and in interaction with the at least one guiding element limits the movement of the metal detector on a specific trajectory;
a drive structure, which comprises a drive element and a rotation connector, wherein the rotation connector connects the drive element with the metal detector, so as to convert a rectilinear motion of the drive element into the motion of the metal detector in interaction with the guided element and the guiding elements.
In another embodiment a pivoting point is arranged at the opposite side of the guided element in relationship to the length of the metal detector. The pivoting point is arranged on the center of the circular arc of the guiding element.
Preferably the frame comprises a first and a second guiding elements with the shape of a circular arc that are symmetrically arranged to a conveyor passing through an aperture of the metal detector wherein the symmetrical arrangement is made with regard to a central point of the aperture in the horizontal plane.
Advantageously the frame with two guiding elements comprises a pivoting point arranged in the center of the metal detector.
Preferably the at least one guiding element comprises a guide groove and the at least one guided element comprise a guide wheel moving with tangential contact inside the guide groove.
In another embodiment the at least one guiding element comprises a guide groove and the at least one guided element comprises an pin element with tangential contact inside the guide groove.
Preferably the at least one guiding element comprises a rail, and the at least one guided element comprises a recess embracing a portion of the rail and being able to be moved along the rail following a precise path.
In another embodiment the at least one guiding element comprises a rail and the at least one guided element comprises a wheel embracing a portion of the rail and being able to be moved along the rail following a precise path.
Preferably the at least one guiding element comprises a rail and the at least one guided element comprises two wheels with tangential contact with the sides of the rail and being able to be moved along the rail following a precise path.
In another embodiment each of the gliding elements comprises a castor structure with roller wheels.
Preferably each of the gliding elements comprises pads of a material with low friction.
In another embodiment the at least three supporting elements are formed by four legs.
In another embodiment an autorotating metal detector installation structure is provided, wherein it comprises:
a frame, which is provided with a guide groove;
a castor structure, which is mounted at the installation bottom legs of the metal detector, and which comprises two roller wheels and a guide wheel, wherein the roller wheels are supported on a support surface of the frame, and the guide wheel contacts tangentally with the guide groove of the frame and rolls therein; and
a rotation drive structure, which comprises a rotation drive element and a rotation connector, wherein the rotation connector connects the rotation drive element with the guide wheel, so as to convert the rectilinear motion of the rotation drive element into the rotational motion of the guide wheel.
Preferably, in the metal detector installation structure of the present invention, the installation structure comprises four castor structures, which are respectively mounted at the four installation bottom legs of the metal detector.
Preferably, in the metal detector installation structure of the present invention, the roller wheel of the castor structure is of a steel-ball-type.
Preferably, in the metal detector installation structure of the present invention, the rotation drive element is a pneumatic cylinder.
Preferably, in the autorotating metal detector installation structure of the present invention, the pneumatic cylinder is the cylinder which can move smoothly.
Preferably, in the autorotating metal detector installation structure of the present invention, the rotation drive element is an electric cylinder.
Preferably, in the autorotating metal detector installation structure of the present invention, the installation bottom legs of the metal detector, the roller wheels, the guide wheel of the castor structure, and the rotation connector are connected and secured by bolts.
Preferably, in the autorotating metal detector installation structure of the present invention, an insulating sleeve is mounted between the roller wheel of the castor structure and the bolt.
Preferably, in the autorotating metal detector installation structure of the present invention, the guide wheel is made of an insulating material.
Compared with the prior art, owing to having the aforementioned technical features, when detecting the products with high requirements on metal directivity, the autorotating metal detector installation structure of the present invention drives the metal detector to rotate in a certain angular range, thus avoiding the influences of the directivity of the metals within the product to the reliability of the detection. Hence, the autorotating metal detector installation structure of the present invention overcomes the restriction of the directivity to the detection reliability, thus capable of obtaining a high-precision detection of the products with high requirements on metal directivity by low cost.
After reading the following non-limiting specific embodiments of the present invention, other features and advantages of the present invention will become apparent.
BRIEF DESCRIPTION OF THE DRAWINGSTo make the objectives, features and advantages of the present invention more apparent and easily understood, the embodiments of the present invention are described below in detail in conjunction with the accompanying drawings, in which,
Figure 1 shows a schematic view of the autorotating metal detector installation structure according to an embodiment of the present invention.
Figure 2 shows a partial enlarged view of ‘A’ portion as shown in Figure 1.
Figure 3 shows a perspective view of the autorotating metal detector installation structure according to an embodiment of the present invention.
Figure 4 shows an exploded view of the autorotating metal detector installation structure according to an embodiment of the present invention.
Before any independent features and embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of the construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.
DETAILED DESCRIPTIONFig. 1 shows a schematic view of an autorotating metal detector installation structure according to an embodiment of the present invention. The autorotating metal detector installation structure of the present invention is mainly used for metal detection of products with high requirements on directivity. As shown in Fig. 1, a metal detection conveyor includes a metal detector 10, an autorotating metal detector installation structure 20 and a frame 30. In the illustrated embodiment, the frame 30 is of a square-pipe-shaped structure. The metal detector 10 is installed on the frame 30 through the autorotating metal detector installation structure 20.
Fig. 2 shows an enlarged view of the part indicated in Figure 1. As shown in Fig. 2, the bottom leg 11 is connected to the castor of the autorotating metal detector installation structure 20. The castor includes a roller wheel 21 and a guide wheel 22. In a preferred embodiment, the roller wheel 21 in the castor is a steel ball, but not limited thereto. The steel-ball-type roller wheel 21 is supported on a support surface 23b of the frame 23 in which a guide groove 23a is provided, while the guide wheel 22 contacts tangentially with the guide groove 23a of the frame 23 and rolls therein. The contact between the steel-ball-type roller wheel 21 in the castor and the support surface 23b of the frame 23 is of rolling friction, thus substantially reducing the driving force necessary to the rotation of the metal detector. Besides, owing to the tangent contact of the guide wheel 22 in the castor with the guide groove 23a of the frame 23, the metal detector can rotate smoothly, thus no vibration occurs during rotation, and no interference is applied to the detecting signals, therefore, the precision of the metal detection would be substantially improved.
Fig. 3 shows a perspective view of the autorotating metal detector installation structure according to an embodiment of the present invention, while Fig. 4 shows an exploded view of the autorotating metal detector installation structure according to an embodiment of the present invention. As shown in Fig. 3 and Fig. 4, the autorotating installation structure includes castor structures 25, rotation drive structures 26 and 27, and a frame 23 provided with a guide groove 23a. The castor structures 25 are respectively mounted at the four installation bottom legs 11 of the metal detector. The rotation drive structures include a rotation drive element 26 and a rotation connector 27. In a preferred embodiment, the metal detector installation structure of the present invention includes four castor structures 25, which are respectively mounted at the four installation bottom legs 11 of the metal detector. Each castor structure 25 includes two roller wheels 21 and a guide wheel 22. As mentioned above, the roller wheels 21 are supported on a support surface 23b of the frame 23, while the guide wheel contacts tangentially with the guide groove 23a of the frame 23 and rolls therein. The rotation connector 27 connects the rotation drive element 26 with the guide wheel 22, whereby the rectilinear motion of the rotation drive element 26 would be converted into the rotational motion of the guide wheel 22.
As seen clearly in Fig. 4, the installation bottom legs 11 of the metal detector, the roller wheels 21, the guide wheel 22 of the castor structure, and the rotation connector 27 are connected and secured by bolts 28. An insulating sleeve 24 is mounted between the roller wheel 21 and the bolt 28. The guide wheel 22 is preferably made of an insulating material, so as to ensure the electric insulation between the metal detector 10 and the frame 30. The rotation drive element 26 and the rotation connector 27 are then secured with each other by fasteners 29.
In a preferred embodiment, the rotation drive element 26 is a pneumatic cylinder which drives the rotation connector 27 to move, while the rotation connector 27 drives the bolts 28 (guide wheel 22) to rotate within the guide groove 23a of the frame 23, whereby the metal detector is driven to rotate about its vertical central axis. The pneumatic cylinder 26 is preferably a pneumatic cylinder which can smoothly move, such that the metal detector can rotate smoothly and uniformly.
Although the present embodiment adopts a pneumatic cylinder as the rotation drive element, it can be appreciated that other embodiments of the present invention can employ an electric cylinder to drive the metal detector to rotate.
Compared with the prior art, when detecting the products with high requirements on metal directivity, the autorotating metal detector installation structure of the present invention drives the metal detector to rotate in a certain angular range, thus avoiding the influences of the directivity of the metals within the product to the reliability of the detection. Hence, the autorotating metal detector installation structure of the present invention overcomes the restriction of the directivity to the detection reliability, thus capable of obtaining a high-precision detection of the products with high requirements on metal directivity by low cost.
The foregoing description has been presented for purposes of illustration and description, and is not intended to be exhaustive or to limit the invention to the precise form disclosed. The descriptions were selected to explain the principles of the invention and their practical application to enable others skilled in the art to utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated. Although particular constructions of the present invention have been shown and described, other alternative constructions will be apparent to those skilled in the art and are within the intended scope of the present invention.