State of the art Several types of meat grinders are equipped with mixing rotors and feeding helix. In these machines when the grinder needs to be turned off, the action of the feeding helix and of the mixing rotors is also interrupted.

The problem to be solved is to keep the rotor's and the helix's counter rotation active even when the grinder is turned off. The present invention suggests an optimal, simple and reliable system that solves all the problems that still hinder the meat grinders that are currently used.

Description The invention is now disclosed with reference to the figures of the drawings attached as a unrestrictive example.

Figure 1 represents a cinematic model of working of a meat grinder provided with mixing rotor and feeding helix. It can be noticed the presence of the independent motor (3) provided with inverter (4) to perform the counter-rotation of the rotor (1) and of the helix (2) when the motor (5) of the meat-grinder (6) is turned off.

Figure 1 bis represents the cinematic model of the same equipment during the combined activity of the meat grinder, the feeding helix and the mixing rotor. It is observable the rotation direction of the meat grinder (6), performed by the motor (5) and the rotation directions of the helix (2) and of the rotor (1) both powered by the independent motor (3).

Figure 1 ter represents schematically the functional diagram of the equipment prepared for the rapid emptying of the hopper (10).

Figure 2 represents a side view of the equipment to highlight the presence of the motor (5) of the meat-grinder (6) and the presence of the independent motor (3) with the inverter (4) to maintain the counter-rotation of the helix and of the rotor when the motor (5) is turned off.

Figure 3 represents schematically a longitudinal section of the equipment to highlight the operational position of the meat-grinder (6), of the feeding helix (2) and of the rotor (1).

In said figure 3 small mixing rotors to be applied to the main rotor (1) can be observed and in particular the oblique outline of the small blade (1la) that comes close to the slanted border of the loading hopper (10). It should be noticed that such outlines allow the complete emptying of the hopper to avoid the unhealthy permanence of residuals inside of the machine.

Figure 4 is cross section by the hopper for feeding the product to be ground. By observing the geometry of the bottom of the hopper, it can be noticed that the border (13) of the opening at the bottom of the hopper (10) is placed underneath the external generatrix of the cylindrical helix (2) to obtain the optimization of the efficiency of the mixing blades (11) of the rotor (1) and to allow the complete emptying of the hopper.

Such geometry also allows to perform, after having removed the dredge part (14) of the grinder, the rapid removal of the residual material from the bottom of the hopper. It can be noticed that such rapid removal happens because of the expulsion effect of the feeding helix (2) whose rotation is activated by the independent motor (3) that activates simultaneously also the rotation of the mixing rotor (1).

Figure 5 represents the position of the equipment prepared for the complete rapid emptying operation of the hopper after having removed the dredge from the grinder.

Figure 6 shows the application of a bagging device (12) by the exit mouth of the grinder. It should be pointed out that, during the bagging operation, the ground material is pressed because of the ratio between the section of the feeding helix and the much smaller free section of the grinder and of the bagging device. Such an high compression ratio allows to obtain also the complete de-aeration of the mix, whole specific volume is thus considerably diminished.

The dimensioning and the proportions of the helix's geometry with respect to the geometry and the structural proportions of the grinding dredge and of the bagging funnel allow to obtain the de-aeration of the handled product. Several tests have confirmed that, with no considerable effect on the hourly quantity of the mass of product being handled, the final product presents a considerably decreased specific volume and with highly increased density, as a consequence of the removal of the air, which is present in the product as it enters the machine but not as it exits it. The specific weight of the product is of course constant, but the volumetric dimensions are highly reduced.

It is the evident than the removal of the oxygen in the handled product has positive effects on the conservation of the characteristics of the product, which is eventually bagged in perfectly aseptic conditions.

In the figures each single detail is marked as follows: 1 is a rotor provided with small mixing rotors 2 is a feeding helix 3 is the independent motor for the rotation and the counter-rotation of rotor and helix 4 is the device that inverts the rotation direction of the independent motor 5 is the meat-grinding motor 6 is the grinder 7 the transmission organ that connects the motor (5) with the grinder (6) 8 is the transmission organ the connects the motor (3) with the rotor and the helix.

9 indicates schematically the protective scaffolding of the equipment.

10 schematizes the hopper that loads the products to be mixed and ground. lOa indicates the slanted front wall of the hopper.

11 are the mixing blades on the rotor..

1 la is a oblique small blade that scrapes the slanted front wall lova.

12 indicates a sacking device applied to the mouth of the grinder.

13 Indicates the lower edge of the feeding hopper.

The clearness of the figures highlights the simplicity of the equipment object of the present invention. It is evident that, when the grinder is not active, the mass of product present in the hopper is made run to the hopper, by inverting the direction of rotation of the helix (2).

It is also clear that, by counter-rotating also the rotor (1), the product present in the hopper keeps being mixed by the mixing blades (11).

During the testing period it has been discovered that the combined effect of the counter- rotation of the helix and of the rotors causes a surprising effect of both mixing and kneading. A remarkable homogeneity of the mix and a very small increase of its final temperature have been also detected.

It should be pointed out that the inventive core of this application consists of a combination of factors, such as: - the continuation of the rotor's counter-rotation even when the grinder is off.

- The continuation of the simultaneous counter-rotation of the feeding helix to obtain the flow of the ground mass to the feeding hopper even when the grinder is off.

- The complete removal of the oxygen from the ground product and the consequent decrease of the specific volume of the finished product.

- The quick expulsion of the product from the feeding hopper.

- The scraping off the any residual product from the slanted front wall of the hopper.

- The small increase of the final mix temperature.

The invention of course allows for several variations of practical realization as far as the proportioning and the structural dimensioning are concerned and as well as the materials used in the realization.

Now that the inventive characteristics have been disclosed, any standard technician in this technological field will be able to create without inventive effort, but only through simple logical deductions by reproducing the original characteristics specific of the present invention, meat-grinding equipments with mixing rotor and feeding helix having the characteristics as illustrated in the attached figures and as disclosed in the above description.

It is therefore evident that all the meat-grinders provided with mixing rotor and feeding helix powered by an independent motor that activates their counter-rotation when the motor of the meat grinder is turned off, and that will be realized with the functional characteristics as basically described, illustrated and hereinafter claimed, will be considered as being part of the protection sphere of the present invention.