Household coffee grinder


A47J42/06 - mechanically driven

 

(57) Abstract:

The invention relates to a device for grinding foodstuffs, such as coffee, pepper, and can be used in everyday life, food, medical industry and in agriculture. In a coffee grinder drive motor is made in the form of the mechanical stator winding. As the rotor used a scratch disk with a developed inner surface for the reception of the grains and their subsequent grinding. The rotor works in conjunction with another, a fixed disk having a developed surface, a stator. The invention allows to simplify the design, reduce the cost of manufacturing the device, to increase the service life and reliability of the grinder. 1 Il.

The invention relates to the field of devices designed for grinding food, such as coffee, pepper, cinnamon, and can be used in everyday life, food, medical industry and in agriculture.

It is known device used for grinding food products, comprising a housing with a lid, inside which is placed a working camera, high speed commutator motor, the shaft of which has a horizontal knife.

Grinding in loemogho product, for example coffee grains separately.

However, the practical use of such a machine revealed a number of drawbacks:

low, the effect of the working surface of the knife due to the action of centrifugal force and concentration at the expense of the grains at the periphery;

the impossibility of achieving uniformity of grind (same size) crushed product, because it is "sticking" of the grains to the walls of the working chamber due to the "dead zone" formed due to the gap between the periphery of the knife and the inner surface of the working chamber;

high cost and however small the reliability of high-speed commutator motor;

low efficiency impact grinding action of the tool - knife similar between the angular velocities of rotation of the knife and beans grinded product, because the grains rotate the knife.

There is also known a method of grinding food in manual mills, containing two gear grinders located coaxially and rotatable manually (ed. St. N 1329799 class. A 47 42/04, 1987). Grinding in these mills is due to the tedding these grains between the gear millstones. The disadvantage of this method of grinding is nasawiya options grinders authors came to the conclusion, what is the closest technical solution to declared and adopted for the prototype is a device for milling of leguminous material (ABT. St. N 1329766 class. A 47 42/04, 1987).

Grinding in this unit occurs in the grinding bowl fixed to it a pair of millstones, one of which is fixed and the other mounted on the motor shaft and has a possibility of rotation.

However, the known device has several disadvantages: complex structure, which leads to lower reliability of the entire machine, as well as low-intensity, low quality crushing food, as well as the low efficiency of the working surface grinders due to the action of centrifugal force and concentration at the expense of the grains at the periphery.

The main problem to be solved by the invention is to improve the quality and intensity of crushing foodstuffs, such as coffee, while increasing the reliability of the grinder.

This is achieved in that the drive motor is made in the end of the stator winding fed from the AC sinusoidal current, and the mechanical rotor without windings, which serves as one of the working disks, ptx2">

The drawing shows the proposed device.

The device includes a housing 1 within which is located the disk 2 with a developed surface, which is also the rotor of the mechanical motor 3. The housing 1 has a rubber bearing 11. On top of the housing 1 is closed by a cover 4, which is mounted on the guides 5 fixed disk 6 with a developed inner surface. The extended surface of disk 2 and 6 are made by analogy with the working disks known disintegrator. Between discs 2 and a movable fixed 6 there is a gap 7, which is directly and grinding grains. The cover 4 has a feed hopper 8 with the aperture closed by a hatch 9. Mechanical motor consists of a stator 3 with the winding 10, fixedly mounted in the housing 1 and the rotor 2. The necessary gap 15 between the stator is provided by the shaft 13, mounted in the bearing 12. To avoid getting crushed product on the surface of the stator and the bearing is closed by a strip of copper foil 14.

Coffee beans for grinding are emptied into the working chamber (hopper) 8 through the hole 9 and through the opening in the stationary disk into the surface grinding.

The grinder of rabote which begins to flow of alternating current, frequency of 50 Hz. Occurs rotating magnetic field and the rotor 2 appear eddy currents induced by the magnetic field of the stator 3. These currents determine the occurrence of a magnetic field of the rotor 2. In the interaction field of the stator 3 and rotor 2 (the law of ampere) of the rotor 2 starts to rotate. Coffee beans under the action of gravity and centrifugal forces fall into the hopper 8 into the gap 6 between the fixed and movable 2 drives the grinder is grinding. The finished product under the action of centrifugal force is poured into the casing 1, where after the termination of the grinding is removed when the cover 4.

Ultimately, it is very important for the grinding of the product has a linear speed. In the proposed device is proposed to increase the linear speed of the working body by increasing the radius of the disks coaxially located with the developed work surfaces, in accordance with addiction

V = R,

where

V - linear angular velocity, m/s;

- angular velocity of rotation of the discs (engine), rad/s;

R is the radius (external) working disks, m

Thus, reducing the angular velocity, for example, i once, while increasing their radius in the first time, you can save the line with the ECCA grinding grain according to:

< / BR>
where

m - grain weight, kg;

V is the linear velocity of the grain in m/s

This, in turn, allows the drive motor to the working chamber to use conventional mechanical induction motor when the power supply frequency of 50 Hz, and the rotation speed of 3000 rpm, respectively, but increased the radius of the disks, allowing you to maintain constant linear speed, and therefore, increase the efficiency of grinding grain.

The proposed grinding device has the following advantages: improve the quality of the milled product; increases the reliability of the device (through the use of brushless asynchronous motor); decrease the cost of the mill; increases service life by eliminating complex elements).

Household coffee grinder for grinding food products, comprising a housing with a lid, a working chamber, the working body, made in the form of two coaxial disks located adjacent to each other on the ends of the work developed surfaces, one of which is rotating and the other stationary, and the drive motor, wherein the drive motor is made in video which is one of the working disks, with the possibility of rotation, and located relative to the face of a stator coaxial with the working gap.

 

Same patents:

Coffee grinder // 2110943
The invention relates to household appliances, designed for grinding food, in particular to the mills

Coffee grinder // 2035178
The invention relates to household appliances, namely mills
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