Patent Description:
Further, the present invention provides a method according to claim <NUM>.

An apparatus according to preamble of claim <NUM> is for instance known from <CIT>, namely, a part of an egg sorting machine, more particularly a link in the supply portion thereof.

As is clearly described in this document, eggs are transferred from a first endless conveyor moving in a direction X by carriers on pivoting and upwardly moving swivel arms to a second endless conveyor moving in a direction Y. Each of these conveyors generally has multiple lines or rows of carriers.

In <CIT> the two conveyors comprise systems of grippers, whereby a first system of the first conveyor transfers the eggs from grippers onto carriers positioned on these swivel arms,.

For both transfer moments, the relative velocities are approximately <NUM>/s.

Most clearly, the movement of the three systems, namely the first conveyor, the second conveyor, and the swivel arms, are coupled,.

More particularly, swivel arms with cam followers in well-defined cam paths are used, such that upon a change of velocity in the X direction or in the Y direction proportionally the velocities are adjusted.

In such a functional system as part of a sorting machine, the velocities involved are related to the processing capacity of the machine. The values thereof are absolute values, so that the velocities have values measured with respect to the frame of the sorting machine. Consequently, none of the velocities intended here will have an absolute value of <NUM>/s, that is, the velocity of the frame itself, unless the machine stands still.

To those skilled in the art it will therefore be clear that this prior art apparatus is not suitable for transfer of products between machine parts of which one has the above-mentioned absolute velocity <NUM>/s.

In <CIT> also an egg sorting machine is described, in particular that part of the machine where the eggs are discharged from grippers of the main conveyor into carrier units, for example packaging units. In FIGURES 16b and 16c of this document it is shown how eggs are discharged in a well-defined manner from grippers into nests of packaging units, while the packaging units, as mentioned above, have a velocity of <NUM>/s, in other words, stand still on a frame on which they are positioned.

As is clearly described, these grippers are coupled to a traveling conveyor, whereby, through associated pivoting movements of arms to ends of which the grippers are attached, the grippers are rotated to discharge positions above the nests mentioned in order to be opened at well-chosen moments and the eggs are discharged from a position just above a nest.

<CIT> also discloses an apparatus according to preamble of claim <NUM>.

Also in the apparatus of <CIT>, these arms with grippers are, in their movement, mechanically coupled to the conveyor with which they are moved to the discharge positions.

In the current art of sorting large quantities of products, for example food products, more particularly eggs, fruit, and vegetables such as tomatoes or peppers, the aim is for high processing capacities. In the case of eggs, for instance, this is about sorting machines that can pass up to as many as <NUM>,<NUM> eggs per hour, including supply followed by detection and characterization (weight, breakage), to a packaging unit. Of relevance here is not only the speed of the above-mentioned operations, and in particular that of the conveyor itself, but also, and especially so, the manner in which the eggs are discharged from such a conveyor and end up in the nests mentioned.

To those skilled in the art, it will be clear that given the high processing capacities mentioned, damage can occur especially upon takeover of the products by successive machine parts, and certainly so upon discharge, more particularly ejection and release of the products, directly at the nests. With eggs, this is about unacceptable fracture percentages; with many kinds of fruit and vegetables, this is about bruised spots or worse.

To provide for the above-mentioned deficiencies, the present invention provides an apparatus as described in the introduction, where the shaft of the pivotable arm is driven by a motor with independently controllable speed.

In the art of the sorting machines discussed here, the technical measure according to the present invention is a drastic technical change.

It has been found that this measure yields a series of advantages, namely,.

In particular, such an independent control (of the shaft motor, or more specifically of the respective motor speed) makes it possible, depending on the type of machine, and certainly also depending on the type of products being presented, for example eggs, to have this transfer proceed not only faster but also slower, and thus to transfer or pack also special types of products (for example a batch of weak-shell eggs) without possible damage.

Further, an aspect of the invention is characterized by the measures of claim <NUM>.

Advantageously, there is provided a method for transferring products, for example eggs, from an endless conveyor to carrier units, the endless conveyor comprising transport carriers for carrying along the products. The method may for instance utilize an apparatus according to the invention. In particular, the method comprises:.

Further, extra advantageous elaborations of the invention are set forth in the dependent claims.

Further variants, exemplary embodiments, and associated possibilities and advantages of the present invention will hereinafter be elucidated in detail with reference to a drawing, in which,.

In these FIGURES, for the same parts or designations, the same signs, symbols, or numerals will be used.

In <FIG> a schematic view is shown of a part of an endless conveyor <NUM> of a sorting machine where eggs E are transferred, namely discharged, with therein a first exemplary embodiment of a transfer unit <NUM> according to the present invention.

<FIG> shows an apparatus <NUM> (for example a sorting machine <NUM>) for transferring products, for example eggs, from an endless conveyor <NUM> to carrier units. In the present exemplary embodiment, the endless conveyor comprises one or more lines or rows of grippers <NUM> (also referred to as transport carriers).

Further, the apparatus <NUM> includes a transfer unit <NUM> positioned near the conveyor <NUM>. This unit <NUM> comprises an arm <NUM> pivotable around a shaft <NUM> and having at the end thereof a transfer carrier <NUM>. Thus, the unit <NUM> is configured to have the transfer carrier <NUM> traverse a curve path, in particular a circular path (in particular a part of a circular path, namely from a starting point S to an end point D located at a lower level, see <FIG>). The relative velocities upon takeover from the conveyor and upon transfer to such a carrier unit are virtually <NUM>/s.

With great advantage, the shaft <NUM> of the transfer unit is driven by a motor <NUM> with independently controllable speed (so that a rotation speed of the shaft <NUM>, i.e., shaft speed, is independently controllable). Thus, according to a further elaboration, the apparatus <NUM> may be so configured that the velocity during use, in particular during transfer of a product from the conveyor <NUM>, is readjusted (see e.g. the trajectory in <FIG>). In particular, the above-mentioned motor speed (or more specifically shaft speed) is not constant as a result of control or readjustment of that speed, during product transfer.

The sorting machine <NUM> is represented here, in particular, as a single line or row of grippers <NUM> with gripper halves <NUM> a,b, with movement in a transport direction T. During use, the conveyor can for instance impart a predetermined transport velocity (vtr) to the grippers. These grippers are connected in a known manner with endless chains known per se (not shown) driven by a motor, and, in a manner likewise known, can be opened and closed to clamp eggs E and thus transport them, and later discharge them at a suitable location.

To those skilled in the art it will be clear that also other types of grippers or holders can be used, for example, but not exclusively, small boxes that can be opened, or also suction cups.

The present invention further provides a transfer unit <NUM> as mentioned, which in turn comprises a motor <NUM> as mentioned, with a shaft <NUM> as mentioned, which is driven by the motor <NUM> and which is connected with a pivotable arm <NUM> as mentioned. This arm <NUM> carries at its end a transfer carrier <NUM> (not represented in this <FIG>) for taking over the eggs E from the grippers <NUM>, for bringing the eggs E over to, and transferring the eggs E to a carrier unit <NUM>. In <FIG>, this carrier unit <NUM> is a tray with nests <NUM>. Control of the motor <NUM> may be carried out, for example, by a suitable motor control, for example a controller, computer, control electronics or the like which will be clear to one skilled in the art. Depending on the type of motor, the control may be configured, for example, to regulate electrical voltage or current to be supplied to the motor, for the purpose of regulating or changing a shaft speed as mentioned. Alternatively, the control may be configured to supply to the motor a control signal which comprises a shaft speed to be furnished by the motor, such that the motor <NUM> furnishes this shaft speed under the influence of reception of this control signal. The motor <NUM> may be configured to rotate the shaft in two mutually opposite rotation directions, for example a forward rotation direction and a return shaft direction (as in <FIG>).

As motors <NUM>, for example servo motors or stepping motors can be used, which will be clear to one skilled in the art.

With reference to <FIG>, below, the movements and functions of the various parts will be further elucidated.

In <FIG>, movement and trajectory of the transfer unit are schematically pictured in a graph. Reflected in an X-Y diagram (with X, for example, a horizontal direction and Y a vertical direction) are curves of traversed paths or movements, given a well-defined velocity of the conveyor <NUM> moving in the transport direction T.

These curves match with symbols (dots, circles, etc.) which represent positions in this X-Y diagram. To those skilled in the art, it will be clear that these positions depend on the settings of the sorting machine and of the correspondingly chosen dimensions and settings of the transfer carrier <NUM>.

The graph shown in this <FIG> is a calculation example based on experiments with such a transfer carrier.

Such a succession of symbols forms a sequential order in time, with equal time intervals between these symbols. More particularly indicated between these symbols are greater, equal, or smaller intermediate distances, which, given the equal time intervals just mentioned, accordingly reflect correspondingly greater, equal, or lower velocities.

The meaning of the symbols, signs, and letters used in this <FIG> is explained below.

It can also be seen in <FIG> that prior to R, namely between S and R, the carrier <NUM> accelerates to gain the proper velocity for takeover (in particular a takeover velocity that is equal to or virtually equal to an earlier-mentioned transport velocity vtr of the conveyor <NUM>).

For clarity of the drawings, the forward path +,* and the return path Δ, ◇ are drawn next to each other in <FIG>; in practice, the paths can overlap, at least if the shaft <NUM> is held in a spatially fixed position.

In the drawing, the successive points/positions (of +, *, Δ and <NUM>, respectively) drawn in the circular path can, in particular, reflect mutually the same intermediate periods/measuring moments of the associated parts of the apparatus (in particular the transfer carrier <NUM>). If the points/positions are close to each other, the velocity is low, and if the points/positions are further removed from each other, the velocity is higher (the distance between two neighboring points is therefore a measure of the local rotation speed).

From this, it follows that transfer carrier <NUM> can accelerate from a starting velocity (or angular velocity) zero to a defined transfer velocity, when the carrier pivots from the starting point S to the transfer point R.

Thereafter, upon the movement indicated with * from the transfer point R to the end point D, the carrier <NUM> will slow down to a velocity zero. Thereafter, the carrier can be moved in reverse direction (along the circular path) which entails an acceleration and deceleration again.

The accelerations and decelerations of the transfer carrier <NUM>, in this example, are in particular effected by, at any rate under the influence of, the earlier-mentioned independent control of the motor <NUM>, or shaft <NUM>.

In <FIG> there is shown in isometric view a second exemplary embodiment of a transfer unit <NUM> of the present invention, at a time td, approximately at the moment of start of transfer, viz. , in <FIG> the point R. In this second exemplary embodiment, the transfer unit <NUM> comprises two shafts 20a, 20b which are each independently controllable (by respective, independently controllable motors 23a, 23b).

As the drawing shows, the transfer unit <NUM> catches an egg E in two hand-shaped receiving halves 22a, 22b which are each connected with respective motors 23a, 23b via a respective shaft 20a, 20b through respective arms 21a, 21b. The two receiving halves 22a, 22b are connected through shafts 22aa, 22bb with the arms 21a, 21b and are connected mutually through a cross-bar 22c, itself freely pivoting on shaft ends 22aa, 22bb.

To those skilled in the art it will be clear that the movements and the positions of the receiving halves 22a, 22b are both partly defined by arms 21a, 21b and partly by the cross-bar 21c, while for the position of these halves 22a, 22b and the cross-bar 21c, for example gearwheels engaging into each other and then also functioning as locking mechanisms, or even separate motors for each of the shafts, may be used.

In the next <FIG> there is represented in each case a next position in the trajectory of transfer, namely,.

In <FIG> a same transfer unit <NUM> is represented (as shown in <FIG>), in this <FIG> with a broken line M through the center thereof. With this line, it is indicated that it may be at multiple angles, while the receiving halves by turning (in particular about the respective shaft 22aa, 22bb) can retain their angle to this line and thereby take up a skew position. A turning to such a position makes it possible to correct for a skew position upon receiving between these parts, or in the case of directed delivery to nests of the carrier unit.

It has been found that in this way off center positions of up to <NUM>° can be used, or, stated differently, positions between -<NUM>° and <NUM>°.

To those skilled in the art, it will be clear that for all above-mentioned holders, grippers, suction cups, etc., matching drives for closing and discharging can be used.

In the FIGURES associated with the exemplary embodiments mentioned here, when the product, here an egg E, is always discharged vertically, the transfer carrier <NUM> will always follow a path in a substantially vertical plane (see <FIG>). Furthermore, it will be clear that trajectories in such planes can also follow curves other than those of a circle.

More particularly, the present invention offers the possibility of regulating the velocity of the transfer unit <NUM> in a wide range of velocities, for example from zero to a defined transfer velocity (for example equal to or near the transport velocity vtr) and back again to zero (then to be accelerated and decelerated in reverse direction).

In order that the products, as mentioned earlier, at takeover from the sorting machine <NUM> which carries along the grippers <NUM> in the transport direction T at a transport velocity vtr, be taken over as safely as possible, a velocity vtr will also be set for the transfer carrier <NUM> in that area.

To those skilled in the art, it will be clear that with the drives presently applied, depending on the situation, the velocity can be chosen in a wide range, and may even be greater than the conveyor velocity vtr mentioned.

In summary, by the transfer unit <NUM> a trajectory can be followed from a starting point S at the conveyor <NUM> up to the discharge at a discharge point R at the carrier unit <NUM>, and back again for a next product, with a transfer unit velocity vtf which can be vmax at a maximum, where the velocity vtf of the transfer unit is controllable and is in a range with <NUM> < vtr < vmax. This vmax is for instance determined and/or limited by the type of motor that is used, or also by properties of the egg (or other product E), such as the shell strength or the internal tensile force of the chalazae.

Claim 1:
Apparatus for transferring products, for example eggs, from an endless conveyor (<NUM>) to carrier units (<NUM>), comprising,
- said conveyor (<NUM>) with at least a single row of transport carriers (<NUM>), and
- a transfer unit (<NUM>) positioned near the conveyor (<NUM>), which further comprises an arm pivotable around a shaft (<NUM>) and having at the end thereof a transfer carrier (<NUM>), wherein the conveyor (<NUM>), the transfer unit (<NUM>) and the carrier unit (<NUM>) are adapted to move such that the relative velocities upon takeover from the conveyor (<NUM>) and upon transfer to such a carrier unit (<NUM>) are virtually <NUM>/s, and characterized in that the shaft (<NUM>) is driven by a motor (<NUM>) with independently controllable speed, wherein the transfer unit (<NUM>) follows a trajectory in a substantially vertical plane.