JPS5810093B2 - Magnetic safety devices for food processing machines, etc. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic safety device for use particularly, but not exclusively, in food processing equipment.

Conventional devices of the type described above have a base containing a motor, the base having a shaft on which various tools, such as knives or hacksaws, are attached.

The drive shaft projects into a container for accommodating the tool and the product to be processed.

In some cases, the container is removably mounted on a stand to facilitate cleaning.

The container is similarly closed with a removable lid, the primary purpose of which is to prevent material from flying out of the container.

This equipment must be equipped with safety measures.

The tool is dangerous in the container at high speeds as contact with the tool being driven and rotating can cause serious accidents.

This need is even more pressing for devices used by untrained personnel.

Safety measures must satisfy two conditions.

The motor must stop when a the container is not properly attached to the platform and b the container is properly attached to the platform but the lid is not secured to the container.

The first condition corresponds to the case where the tool is mounted directly on the drive shaft without a container.

The second condition corresponds to the case where the container is in place but the lid is not on it so that hands or fingers can be inserted during operation.

Simply put, any contact with rotating tools must be prevented.

This result depends on the presence of working contacts on the stand, which are connected in series with the supply circuit of the motor, and whether the container and lid are in the proper position, i.e. whether the lid is fixed to the container or not. , by making the contacts open or closed depending on whether the container is fixed to the stand or not.

One solution has already been proposed in US Patent No. 3,892,365 (Pi
erre Verdum).

In that patent, the container is secured to a stand by bayonet-like means to ensure precise positioning.

The cylindrical container has a duct extending along the generatrix, and the duct contains a pusher.

The lid is secured by a stop in the upper position, and a cam presses against the upper end of the pusher so that when the lid is secured, the pusher is pushed downward and its lower end presses the electrical switch through a hole formed in the base.

If the duct does not face the hole, i.e., the container is not in the proper position on the base, the pusher cannot enter the base, and unless the cam presses the upper end of the pusher, i.e., the lid cannot be fixed to the container. As long as the pusher does not enter the base, the above conditions are satisfied.

However, the device described above is completely unreliable since, for example, a child can insert a sharp object into a hole in the base to activate the working contact and thus rotate the drive shaft even when the container is not in place. I can't say it's expensive.

The motor can also be started by pressing the pusher end even when the container is in place.

Further, the pusher, which is pushed up by a spring, is difficult to clean and maintain.

SUMMARY OF THE INVENTION The object of the present invention is to eliminate the above-mentioned drawbacks and to assemble a more reliable safety device.

The present invention is a magnetic safety device for a food processing machine or other electrical appliance, comprising a base, a motor housed in the base, an electrical control circuit for the motor, a container, and a removable device for the container. means for fixing the container on the base in the operating position, a duct extending along the generatrix of the container, a magnetic conductor connected to said control circuit and provided in the base; a working contact controlled by a working contact such that a switch of the magnetically controlled working contact is located below the duct when the processing vessel is in the working position, and a working contact controlling the working contact; To provide a safety device characterized in that it includes at least one permanent magnet provided in a processing container for the purpose of protecting the processing vessel.

In the aforementioned patent, the pusher enters the base so that information that the lid is secured is mechanically transmitted, thus starting the motor.

In the present invention, such information is instead conveyed by the magnetic flux of the magnet, which is not applied to the working relay until all elements are fixed.

This is a direct advantage. Since the base is molded from non-magnetic plastic, it is no longer necessary to make holes in the base.

The position of the magnetically controlled contacts on the outer circumference of the base is
It is invisible as well as the pores should be.

Additionally, the safety device can only be activated by the person in possession of the magnet.

This greatly reduces the risk of starting the motor improperly.

The features and advantages of the invention will become apparent from the following preferred embodiments explained with reference to the drawings.

Like numerals indicate like elements in all figures.

In FIG. 1, a hollow base 1 is made of molded plastic, for example.

A motor 2 is housed in the base, and its axis is vertical and extends all the way through the ceiling 1a of the base.

Another method is to connect the vertical output shaft of the reduction gear to the ceiling 1a.
, the input shaft of which is connected to the output shaft of the motor 2, which may be placed parallel to the container.

A removable, e.g. cylindrical, container 3 has a bottom 3a provided with a hole through which the shaft of the motor 2 or the output shaft of the reduction gear passes when the container is placed on the base 1 as shown in FIG. .

The tool 4 has a radial knife 4a and cuts the base 1 in a suitable manner.
It is connected to the end of the shaft in the overlying container 3.

The above-mentioned known processing machines with rotating tools are equipped with mechanical safety devices known from the above-mentioned patents.

This safety device has a control button 5a, which is fixed in a hole 6 formed in the horizontal part 1b of the base, which is located under the cylindrical skirt 3b extending downward from the bottom 3a of the container 3. It mainly consists of working contacts 5.

The hole 6 is located precisely under the duct 7 formed along the generatrix of the container 3.

The duct 7 is adapted to receive the container 3 and the pusher 8, which is preferably made of a synthetic material such as polycarbonate and preferably made of an electrically insulating material.

A spring 9 is provided between the bottom of the duct 7 and the central portion of the pusher rod 8 and acts to push the pusher rod 8 upward.

As shown in FIG. 1, a collar is fixed to the upper end of the pusher 8, which is close to the upper end of the duct 7.

The pusher 8 also has at its lower end a cylindrical acting means 8a which passes through the hole 6 and acts on the pusher 5a of the switch 5.

The upper end of the pusher 8 extends to an actuating means 8b, which is substantially connected to a flange or external projection 10a which forms a cam and is molded integrally with the lid 10 or is secured to the lid by suitable means. It cooperates with the slope 10b located on the outer periphery.

The cam 10b pushes the pusher 8 downward when the lid 10 is in a predetermined position and the skirt 20 is fitted, compressing the spring 9 so that the lower acting means 8a passes through the hole 6 and acts on the contact 5. It's in a good position.

According to the invention, the second working contact 11 is located in the base 1, for example under the cylindrical scar (3b) of the container 3, below the plane part 1c which is diametrically opposite and substantially at the same level as 1b. It is placed under the .

A permanent magnet 12, made of ferrite, for example, is fixed to the skirt 3b in such a way that the magnetic control contact 11 is exactly at the bottom, the container 3 is placed on the base 1, and the pusher 8 is placed exactly in the hole 6.
The magnet 12 activates the contact 11 when it is above the .

According to another feature of the invention, the magnetic working contact 11 and the mechanical working contact 5 are connected in series to the supply circuit of the motor (
(not shown) In the case of the device shown in FIG. The tool 4 does not rotate unless the cam 10b acts on the pusher 8 and compresses the spring 9 in the closed position.

In such a position, the flange 10c of the lid also stops at the stop 1.
7 to prevent the lid from moving upward.

If the lid is not in place or improperly closed, mechanical contact 5 will open the circuit and the motor will not start.

A similar situation occurs if the container 3 is not placed on the base, since the supply circuit of the motor 2 is also cut by the magnetic contacts 11.

In the latter case, for example, a child can actuate the pusher 5a of the contact 5 by placing the tool 4 on the tip of the shaft protruding from the ceiling 1a of the base and inserting a sharp object into the hole 6.

However, even if such an operation is performed, the supply circuit of the motor 2 is interrupted by the contact 11, so that dangerous rotation of the tool 4 does not occur.

2 and 3 show the upper fabric portion of the device of FIG. 1 with a single magnetically controlled safety device.

The only difference between this device and the device of FIG. 1 is that the magnetic control contacts 11 are provided in the base 1 below the plane 1b without any holes.

A cylindrical permanent magnet 12 is fixed to the lower end of the pusher 8.

In this case a single working contact 11 is inserted into the supply circuit of the motor 2.

Of course, when the container 3 is not placed on the base 1, the contact 11 will not be actuated by the magnet 12 fixed to the container 3, and no mechanical action on the base 1 will start the motor. Can not.

The same is true when the container 3 is properly placed on the base but the lid 10 is not closed or is improperly closed.

Only when the lid 10 rotates to an appropriate position, the cam 10b pushes the pusher 8 downward through the upper end effector 8b and compresses the spring 9, and the permanent magnet 12 approaches the contact 11 (FIG. 3), the contact 11 Close to start the motor and operate the tool.

A slightly different embodiment is shown in FIG. 4, but the vertical cross-section of the food processing machine is the same.

In FIG. 4, the device is shown with a magnet 12 fixed to the lid 10 by suitable means, in particular a magnet 1 provided on the flange 10a of the lid.
It has 2.

Magnetic flux must be applied to contact 11 as before.

According to another feature, the magnetic flux is transmitted to the contact 11 by a rod 12a of ferromagnetic material, such as soft iron or ferrite, which rod is fixed in the duct 7.

In FIG. 4 the device is in the operating position.

That is, the lid 10 rotates on the container 3, so that the a flange 10
c engages the stop 17 (although not shown in cross-section, the same device is also present on the flange 10a), b permanent magnet 12
is brought onto the rod 1 and thus the rod 7 is magnetically polarized and transmits the polarity to the contact 11, which closes the supply circuit of the motor 2.

As the lid rotates, guided by the internal skirt 20 that ensures a tight seal, the flange moves away from the stop and the lid 1
0 is released and the magnet 12 separates from the rod 12a,
The magnetic field disappears and the working contacts 11 open and the motor stops.

A rod 12a made of ferromagnetic material is used to reduce the air gap.
H is placed in the plastic of the duct 7, for example, and abuts a very thin bottom wall 29 and top wall 30 to prevent loss of magnetic flux.

A different type of tool from those described above is shown in dotted lines in FIG.

That is, a shredder plate 15 is provided on the shaft of the motor 2 through the bub 14.

To use this breaking tool, the product must be fed to the rotating plate 15.

This is done in a known manner by means of the chute 13 into which the pusher 16 is inserted.

In all embodiments, magnetic contacts H1, L, S type contacts are preferred, and R, T, C, LARAD-IOTECHN
RI223A, known as a reed relay manufactured by IQUE-COMPELEC.

RI22A or RI42 are preferred.

The above-described embodiment has the advantage that the switch 11 has parts that move when it is opened or closed.

It should be noted that the safety device is placed on a device consisting of a base with a first element (container 3).

The second element (lid 10) can be fixed in position such that the magnet 12, the axis of the duct 1 and the magnetic contact 11 are in line.

In the latter case the magnet is fixed to the lid.

Figures 5 to 8 show another embodiment, but as before the information that the lid is fixed is conveyed by a lot of ferromagnetic material.

In FIGS. 5 and 8, the magnet 12 is fixed to a pusher that passes through the chute 13 instead of the lid.

5 is a sectional view along a vertical plane of a food processing machine or kitchen robot of the type previously described in FIG. 5; FIG.

FIG. 7 is a plan view of a cross section taken along the line ■-■ in FIG. 5.

FIG. 5 shows the base 1, the container 3 and the lid 10, the lid 10 having a chute 13 with a pusher for inserting the product upwards and pushing the product down, and a hand and a rotary tool 15. No contact is to occur between them.

As before, the container is fixed in place on the base by bayonet-like fittings or screws, such that the duct 7 is in line with the working contact 11 mounted on the base.

A lid 10 is molded integrally with the container 3 at its upper end and is secured by a stop 17 located on flanges 10a, 10c formed on the lid.

Stop 17 is shown in FIG.

The stop cooperates with a diametrically opposite stop (not shown) to secure the lid in position on the container, so that the lid is also secured in position with respect to the base.

According to the invention, the container 3 has a duct 7 along one of its generatrices, the duct having a lot 12a of ferromagnetic material, such as soft iron.

When the container is placed on the table as shown in FIG. 5, the lower end of the rod 12a faces the magnetic switch 11 located just below the plane 1b of the table 1.

In the example of FIG. 5, the duct 7 extends above the container 3. It is substantially equal to the total height of the lid 10 and the chute 13.

The pusher 16 has a permanent magnet 12 along one of its side walls with a strong magnetic field (eg 40,000 Gauss).

The operating dimensions of this device are self-explanatory.

When the pusher 16 is inserted into the chute 13, the magnet 12
opposes rod 12a and magnetically polarizes it.

The polarity is transmitted to the lower end of rod 12a and actuates contact 11, thus closing the contact and starting the motor since it is connected to the motor's supply circuit.

As shown in FIG. 7, the contact 11 will not operate unless the magnet 12 is accurately opposed to the lot, that is, the lid is not fixed to the container.

Such features offer many advantages.

For safety reasons, the chute of known devices must be dimensioned such that the height of the chute is greater than the length of a finger, so that a hand or fingers cannot be inserted into it.

The resulting fruit shoots have a high height and a small cross-sectional area, making it difficult to break up some types of vegetables.

This is because the vegetables must be cut into small pieces in advance.

As a result of the invention, the cross-sectional area of the chute is enlarged to a size sufficient for cooking needs.

This is because the pusher itself starts the motor when it is inserted into the chute.

As a result, no part of the child or hand comes into contact with the rotating tool.

As shown in FIG. 7, the cross-sectional area of the chute 13 is considerably enlarged.

The rod 12a is also coated with, for example, micron metal (μmmetal) on the entire circumference of the duct 1 except for the area facing the magnet 12.
l) By providing a magnetic film as described above, protection from external magnetic influences can be achieved.

In order to simplify certain manufacturing issues, FIG.
An example is shown in which the container is divided into a portion a1 and a portion 12a2 which is fixed to the container 3.

The two parts may be molded together with the container or lid, or may be molded and then bonded together.

When the container 3 and lid 10 are properly placed, the rods 12a1 and 12a2 are in line, and 12al is aligned with the magnet 12.
This polarizes 12a2, resulting in a change in the state of contact 11.

If a knife is used, all ingredients are inserted into the container before it is capped, and the motor is started by inserting the pusher 16 into the chute 13.

In such cases the pusher merely provides a safe closure.

However, it may be necessary to insert the product while the device is running without stopping.

In such a case, a pusher 16 that includes a magnet 12 and has a funnel-shaped inner wall, such as the wall 18 of the pusher 16 shown in FIG. 8, may be used.

The wall 18 allows the insertion of liquid or powdered products, but is shaped to prevent finger jamming.

However, in some cases the reluctance of the magnetic circuit may be too high for completely reliable operation.

In such a case, the safety device will be inactive even when the above-mentioned conditions are met.

Means for avoiding such disadvantages will be explained below.

FIGS. 9 and 10 again show two states of a single safety device of the invention applied to a food processing machine, only a portion of which is shown in the figures.

As before, FIGS. 9 and 10 show a lid 10 with a base 1, a container 3 and a chute 13. FIG.

The figure is a sectional view along a vertical plane passing through the axis of the container and the axis of the duct 7.

As a result, permanent magnet 12 is only shown in FIG.

As in the previous example, the magnet 12 is fixed to the flange 10a of the lid 10.

However, as before, the ferromagnetic rod in the duct 7 above the magnetic actuating contact 11 is replaced by a movable assembly consisting of a rod 23 with permanent magnets at both ends (i.e. magnet 19 at the lower end and magnet 22 at the upper end). Thin covers 29 and 30 are fixed to the three-dimensionally replaced duct 7 at its lower and upper ends, respectively.

The rod 23 is slidable between walls 29 and 30 in the duct 7 by suitable means.

In the center of the rod 23 there is a collar 24 which contacts the = end of the spring 9, and the other end of the spring 9 contacts a ring 25 formed in the duct 7.

A feature of this example is that the facing poles of magnets 12 and 22 have the same polarity, that is, if the bottom end of magnet 12 is a north pole, the top end of magnet 22 is also a north pole, or vice versa.

The operation of this device is simple.

That is, in FIG. 9, the container is fixed to the stand, but the lid is not fixed to the container.

Magnet 12 has no effect on magnet 22 and spring 9 presses the top surface of magnet 22 against wall 30.

When the lid 10 is rotated over the container 3 guided by the inner skirt 20, the lid is fixed and the magnet 12 is brought over the duct 7.

The magnets 12 and 22 are repulsed by each other, thus causing the rod assembly to move downward.

As a result, the spring 9 is compressed and the magnet 19 comes into contact with the wall 29, as shown in FIG.

The air gap between the magnet 19 and the magnetic material of the contact is small;
Contact 11 changes state to close the motor supply circuit.

As soon as the lid is unfastened, the spring 9, which was compressed during the lowering of the rod 23, stretches and the magnet 22 returns to its upper position, so that the magnet 19 moves away from the contact 11 and the motor supply circuit opens.

The ring 25 guides the movement described above and the magnet may touch the inner wall of the duct 7 only slightly.

Other embodiments are shown in FIGS. 11 to 13.

FIG. 11 is an overhead view of the lid 10 of the device equipped with the means according to the invention.

There are two diametrically opposite ears or flanges 10a and 10c around its periphery.

The flange 10c is bent into a U-shape so as to surround a stop provided on the container 3 when the lid is rotated.

The same thing is done for ear 10a, but ear 10a
A lid (not shown) also abuts the edge of the container to limit angular movement over the container.

The lid also has two vertical magnets 12 and 31 fixed to the flange 10a, with the polarities of these magnets being opposite, i.e., if the bottom end of magnet 12 is the south pole, the top end of magnet 31 is the south pole. or vice versa.

FIG. 12 is a partial sectional view taken along a vertical plane passing through the axis of the container 3 and the axis of the duct 7.

As before, the safety device has a magnetic contact 11 located below the duct 7.

However, in FIG. 12 the movable assembly consists of a tube 27 filled with gas (for example air) and closed at both ends with magnets 19 (lower end) and 32 (upper end).

In the duct 7 the assembly is immersed in a liquid such as oil having a density such that the Archimedean buoyancy force is comparable to the weight of the tube and the tube 27 is substantially balanced.

As shown in FIG. 11, there are two positions of the lid that correspond to when the magnet 12 or 31 is brought onto the duct γ.

In the case shown in FIG. 12, the lid is in a fixed position and the magnet 12 is above the duct 7.

Magnet 12, 32. are of the same polarity, so that as a result of the magnetic repulsion tube 7 is pushed downwards and magnet 19 approaches contact 11, which changes state and closes the supply circuit of the motor.

After using the device, when the lid is rotated to unfasten and the product is removed from the container, the magnet 12 is replaced by the magnet 31 at the top of the duct 7.

Magnet 31 has an opposite polarity to magnet 12 and therefore also to magnet 32, so that magnetic repulsion is replaced by magnetic attraction.

The tube 27 rises and the magnet 19 moves away from the contact point 11.
The contacts open and the motor stops.

It should be noted that the rotation that replaces magnet 12 with magnet 31 also releases flanges i0a and 10c from stop 17.

In other embodiments, the lid may only have one magnet of the same polarity as magnet 32.

In this case, however, the density of the liquid 28 and/or the weight of the tube must be such that the tube 27 rises with a simple force without any magnetic force.

The contact between magnets 19 and 11 is thus automatically broken.

Although the last example relates to the case where the actuating magnet 12 is fixed to the lid, it can of course be effectively used to start the motor by inserting a pusher into the chute.

In the example explained so far, the only magnetic relay,
It used contacts or switches.

Of course, more than one contact can be connected in series with the supply circuit of the motor according to the invention.

For example, a lid safety switch and a chute safety device can be provided.

It is also possible to connect the safety switches in the container position in series.

Finally, the invention can also be advantageously applied if the motor is located parallel to the container in the casing, rather than underneath the container, by providing one or more contact points in the vicinity of the container, lid and chute. .

Of course, the present invention is not limited to the embodiments described so far.

[Brief explanation of drawings]

Figure 1 shows a food processing machine equipped with the safety device of the present invention.
FIG.
The figure is a front sectional view showing an example of the safety device of the present invention, FIG. 4 is a front sectional view showing still another example of the safety device of the invention, and FIG. 6 is a front sectional view showing still another example of the device; FIG. 6 is a front sectional view showing an example of the safety device of the present invention similar to that in FIG. 5; and FIG. It is a plan cross-sectional view along the line 2, and the 8th
Fig. i is a front sectional view showing one example of the pusher of the food processing machine of the present invention; Figs. 9 and 10 are front sectional views showing still another example of the safety device of the invention; Fig. 11; 11 and 12 are overhead views of the lid portion of the safety device of the present invention, and FIGS. 12 and 13 are front sectional views showing still other examples of the safety device of the present invention. be. 1: Base, 2: Motor, 3: Container, 4: Tool 10: Lid, 11: Working contact, 12: Permanent magnet, 13: Chute,
16: pusher, 7: duct.

Claims (1)

[Claims] 1. A magnetic safety device for a food processing machine or other electrical appliance, comprising a base, a motor housed in the base, an electrical control circuit for the motor, a container, and a device for removing the container. a processing container with a lid that can be secured, means for securing the container on the base in the working position, a duct extending along the generatrix of the container, a magnetic field connected to said control circuit and provided in the base; a magnetically controlled working contact such that a switch of the magnetically controlled working contact is located below the duct when the processing vessel is in the working position; 1. A safety device, characterized in that it comprises at least one permanent magnet installed in the processing container for controlling it. 2. A pusher slidably mounted in the duct and having a permanent magnet fixed to its lower end, the permanent magnet moving toward or away from the working contact under the action of a cam held in the lid and in contact with the upper end of the pusher. 2. The safety device according to claim 1, wherein the safety device changes the state of the working contact at certain times. 3. A rond made of ferromagnetic material is provided along the entire length of the duct, and a permanent magnet is fixed to the lid. 2. A safety device according to claim 1, characterized in that the permanent magnet is above the duct when the lid is fixed to the container. 4. A movable assembly is slidably disposed within said duct, and when the container and lid are secured, permanent magnets affixed to the lid are brought above said assembly and at each end of said assembly. 2. A safety device as claimed in claim 1, characterized in that the permanent magnet has a magnet at the upper end of the assembly, the polarity of the permanent magnet being the same as the polarity of the magnet at the upper end of the assembly so as to be repulsive. 5. Safety device according to claim 4, characterized in that the movable assembly consists of a rond which returns to its uppermost position by means of a spring. 6 The movable assembly consists of a gas-filled tube. 5. Safety device according to claim 4, characterized in that said tube is immersed in liquid in said duct. 7. A safety device according to claim 6, characterized in that the tube is balanced midway within the duct. 8 Magnetic safety devices for food processing machines or other electrical appliances, including bases, motors housed in the bases, electrical control circuits for the motors, containers, and removably fixed to containers. means for fixing the container on a base in the operating position; a duct extending along the generatrix of the container; a cam slidably mounted in the duct and whose lower end is supported by the lid; a pusher whose lower end is adapted to be actuated to press a bush button on an electromechanical switch; a magnetically controlled actuating contact connected to said control circuit and provided in the base; 1. A safety device comprising a permanent magnet mounted on a container facing the contacts, the switch and the working contacts being connected in series to a control circuit of a motor. 9 A base containing an electric motor, a container closed by a lid that can be placed on the base and fixed, a lid with a chute for inserting the product, an electrical control circuit for the motor, a base in the operating position. means for fixing the container on the platform; a duct extending along the generatrix of the container; and magnetically controlled working contacts connected to the control circuit and provided in the base so that the container is in the actuated position. a magnetic safety device comprising a working contact such that a switch of the magnetically controlled working contact is located below the duct when the working contact is in the duct; and at least one permanent magnet for controlling the working contact. In the food processing machine with Food processing machine, characterized in that it is adapted to transmit to magnetically controlled working contacts. 10. Claim 9, characterized in that the magnetic circuit comprises a rond of magnetic material extending along the generatrix of the container and into a duct fixed to the container between the base and the upper end of the chute. food processing machine. 11 The magnetic circuit comprises two irons made of ferromagnetic material, one of which is fixed to the container and the other to the lid, and the container is fixed to the base and the lid is fixed to the container. 9. The food processing machine according to claim 9, wherein the two ronds form a line with the working contact, thus magnetically connecting the permanent magnet to the contact. . 12. The food processing machine according to claim 9, wherein the cross section of the pusher is such that the magnet faces and is located close to the ferromagnetic rond when the pusher is inserted into the chute. 13 Claims 9 to 12, characterized in that the pusher has a funnel-shaped inner wall for inserting the product.
The food processing machine described in any of paragraphs. 14. Food processing machine, characterized in that it has at least one safety device according to any of the preceding claims and magnetically controlled working contacts connected in series with the motor supply circuit. 15. A food processing machine comprising a magnetic safety device according to any one of the claims above and another safety device provided in series.