JPS643673Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a meat cutter, and more particularly to a meat cutter equipped with a braking circuit that stops a meat box at a front stop position.

In the conventional meat cutter with a meat box front stop device,
If the cutting resistance of the meat loaf applied to the cutter becomes excessive during the cutting operation of the frozen meat loaf, the electric motor for rotating the knife and driving the meat box becomes locked, and the cutting operation of the meat loaf is interrupted. It was hot. In this case, in order to resume cutting work, the worker operates the power switch or operation switch to cut off the power supply to the motor, and then manually operates the reversing switch intermittently to turn off the power to the motor. Since the power supply was phase-switched and the power was turned on intermittently to reverse the motor and return the meat box to the front stop position, it was difficult to stop the meat box accurately at the front stop position.
Accurately stopping the meat box at the front stopping position requires skill and is a troublesome task. In addition, if the meat box deviates from the front stop position, there will be problems such as impact being applied to the machine body and the meat loaf being cut unnecessarily when the cutting operation is resumed.
It was necessary to accurately return the meat box to the front stopping position.

The present invention was developed in view of the above, and its purpose is to facilitate the reversing operation, to accurately stop the meat box at the front stop position, and to prevent the meat box from cutting during the cutting process. The purpose of the present invention is to provide a meat cutting machine that can enhance safety.

The feature of the present invention is that the electric motor that reciprocates the meat box through a speed reducer and a crank mechanism is a reversible electric motor that can rotate forward and reverse. a load detector for detecting an overload on the electric motor during the cutting operation of a meat loaf stored in the meat box in which the forward rotation drive circuit is operating; A comparator circuit that receives a signal and compares the magnitude of whether the load condition is above a preset load condition and sends out an output signal when the load condition is above the preset load condition, and when the output signal of this comparator circuit continues for a predetermined period of time. an overload control circuit that stops the operation of the forward rotation drive circuit; a position detector that detects that the meat box has reached the morning stop position when the electric motor rotates forward and reverse; a motor reversing drive means for operating the reversing drive circuit to reverse the electric motor when the operation is stopped by the overload control circuit; Meat box stop control that stops the operation of the reverse drive circuit and operates a braking circuit that brakes the electric motor in response to a detection signal detected by the position detector to stop the meat box at the front stop position. The point is that the configuration is equipped with means.

The present invention will be explained in detail below with reference to the embodiments shown in FIGS. 1 to 3 and FIG. 4.

FIG. 1 is a schematic front view showing an embodiment of the meat cutting machine of the present invention. In FIG. 1, supporting member 1
Two parallel sliding members 2 are arranged on the upper surface of the meat box 3, and a meat box 3 is supported and fitted onto the sliding members 2 so as to be able to reciprocate (in the front and rear directions in the figure). meat box 3
One end of an arm 4 is rotatably supported at the bottom of the arm 4, and the other end of the arm 4 is rotatably supported by a crank 5. 6 is the electric motor for driving the meat box (hereinafter referred to as IM
) is connected to a speed reducer 7 via a power transmission mechanism such as a belt, and a crank 5 is fitted onto the output shaft of the speed reducer 7. Therefore, I.M.
6 rotates the crank 5 via the reducer 7, which causes the meat box 3 to reciprocate back and forth via the arm 4.

The cutter 8 is rotated by a cutter rotating electric motor and a power transmission mechanism (not shown). That is, when the operation switch 9 is operated, the cutter 8 rotates and the meat box 3 reciprocates, cutting the meat loaf stored in the meat box 3 continuously or intermittently.

Reference numeral 11 denotes a position detection unit of the meat box 3, which detects the presence or absence of the protrusion 12 fixed at the proper position on the output shaft 7a of the reducer 7 and the protrusion 12 fixed at the proper position on the support member 1, as shown in FIG. The detector 13 detects the meat box 3 during forward rotation, and the detector 14 detects the meat box 3 during reverse rotation.
Detects that the has reached the near stop position.

FIG. 3 is a block diagram showing one embodiment of the control circuit for the meat cutter of the present invention. In FIG. 3, normally open relay contacts 36a, 37a are connected in series between two lines _l2 , _l3 of the power lines _l1 , _l2 , _l3 and IM6, and normally open relay contacts 36a When it closes, the knife 8
A blade rotating electric motor (not shown) that rotates the blade and IM6 rotate in the normal direction, and when the normally open relay contact 37a closes, the IM6 rotates in the reverse direction. moreover,
A normally open relay contact 38a is provided, one of which is connected to the V and W terminals of IM6, and the other both connected to the anode side of thyristor 34. The cathode side of the thyristor 34 is connected to the power supply line _l3 . 35 is a trigger circuit, which outputs a trigger signal synchronized with the power supply while the normally open relay contact 38a is closed, and the thyristor 34
ignite. When thyristor 34 fires, IM
A braking current flows through IM6, and IM6 stops. These normally open relay contacts 36a, 37a, and 38a are respectively closed when relay coils 36, 37, and 38, which will be described later, are excited.

FIG. 4 is a time chart of signals of each part in FIG. 3 to explain the operation of FIG. 3.
correspond to a to r in FIG. The operation shown in FIG. 3 will be explained below with reference to FIG.

(1) When performing normal meat cutting work When the operation switch 9 is operated to turn on, the output signal a is inverted from logic "L" to logic "H" as shown in Figure 4 a. . At this time, OR circuit 18
The output signal m is a logic "L" as shown in FIG.
Therefore, when the output signal a of the operating switch 9 rises, the Q output signal O of the D flip-flop 15 is inverted from logic "L" to logic "H" as shown in FIG. 4o. This output signal O excites the relay coil 36 via the amplifier circuit 31, the normally open relay contact 36a closes, and the blade rotation motor and IM6 rotate normally. Therefore, the cutter 8 rotates, the meat box 3 moves back and forth, and the meat loaf stored in the meat box 3 is cut. When finishing the cutting operation, the operating switch 9 is turned off and the output signal a is inverted from logic "H" to "L". The logic "H" signal obtained by inverting the logic "L" output signal a by the inverter circuit 24 and the logic "H" Q output signal O of the D flip-flop 15 are input to the AND circuit 23, and the AND circuit 23 is also input with the detection signal C of the detector 13, and after turning off the operation switch 9, when the detector 13 senses that the meat box 3 has reached the front stop position and outputs the detection signal C, Under the above conditions, the AND circuit 23 allows the detection signal C to pass through. On the other hand, during normal cutting work, the Q output signal q of the D flip-flop 16 is at logic "L" as shown in FIG.
The detection signal d (fourth
d)), the output signal e of the OR circuit 19 becomes one logic "H" pulse corresponding to the detection signal C, as shown in FIG. 4e.

The output signal e of logic "H" is inputted to the D flip-flop 15 as an output signal m (see FIG. 4 m) via the OR circuit 18, thereby clearing the D flip-flop 15, and outputting the Q output of the D flip-flop 15. Signal O is inverted from logic "H" to logic "L". Therefore, the relay coil 36
excitation is stopped, the normally open relay contact 36a is opened, and the power supply to the blade rotation motor and IM6 is cut off. In addition, the output signal e of the OR circuit 19
The timer 25 starts operating at the falling edge of the signal when the logic is reversed from logic "H" to logic "L", and for a preset time _T2 , the output signal p of the timer 25 is as shown in Figure 4 p. becomes logic “H”. The relay coil 38 is excited via the amplifier circuit 33 by this logic "H" output signal p, the normally open relay contact 38a is closed, the trigger circuit 35 is operated, and the thyristor 34 is ignited for a set time _T2. do. Therefore, a braking current flows through the IM 6, and the meat box 3 stops at the front stop position. The setting time T ₂ is
The time is set in advance to be sufficient to stop the meat box 3.

(2) During the cutting operation of the meat loaf, the cutting load resistance of the meat loaf applied to the knife 8 increases, the rotation of the knife 8 is about to stop or stops, the movement of the meat box 3 also stops, and IM6
In this case, the power detector 28 detects the load current of IM6 and outputs an AC signal proportional to the load current.
Since the output signal f of increases as shown in FIG.
9, the output voltage signal g increases as shown in FIG. 4g. This output voltage signal g (voltage V) is input to the comparator 30, and the preset IM6
The magnitude is compared with the reference voltage Vref corresponding to the overload current of 6, and when V<Vref, the comparator 3
The output signal h of 0 is logic "L" as shown in FIG. 4h, but when V>Vref, it is inverted from logic "L" to logic "H". Therefore, since the Q output signal O of the D flip-flop 15 is logic "H", the output signal i of the AND circuit 21 is also inverted from logic "L" to logic "H" as shown in FIG. 4i. At the rising edge of this output signal i, the timer 26 starts operating, and for a preset time _T1 ,
The output signal j of the timer 26 becomes logic "L" as shown in FIG. 4j. Setting time T ₁ or more AND circuit 2
When the output signal i of 1 is at logic "H",
That is, when the IM6 is overloaded for more than the set time _T1 , the rising edge of the output signal j of the timer 26 causes the Q output signal k of the D flip-flop 17 to change from logic "L" to logic "L" as shown in FIG. It becomes "H" and clears the D flip-flop 15 via the OR circuit 18. Therefore, the Q output signal O of the D flip-flop 15 changes from logic "H" to logic "L" as shown in FIG.
6a opens, cutting off the power supply to the electric motor for rotating the cutter and IM6, and preventing the rotation of the cutter 8 and the meat box 3.
Stops driving. Here, the set time T ₁ is
At the start of cutting the meat, the D flip-flop 17 is prevented from operating due to the starting current of the IM6.
The time range is longer than the time during which the starting current flows and does not burn out the IM6, and is generally set to about 1 to 3 seconds. Also, if IM6 is overloaded, timer 2
6, the voltage V of the output voltage signal g of the voltage conversion circuit ₂₉ becomes lower than the reference voltage Vref, so the output signal h of the comparator 30 changes from logic "H" to logic As a result, the Q output signal k of the D flip-flop 17 remains at logic "L" and the output signal l remains at logic "H" as shown in FIG. Ru.

(3) When the cutter 8 and the meat box 3 are stopped while the cutter 8 is biting into a lump of meat, when this state is to be released, the output signal n of the OR circuit 20 is determined by the logic " Therefore, when the operation switch 10 is operated once and turned on, the output signal b is inverted from logic "L" to logic "H" as shown in FIG. 4b, and the rising edge of the signal at that time Then, the Q output signal q of the D flip-flop 16 is inverted from logic "L" to logic "H" as shown in FIG. 4(q). This output signal q excites the relay coil 37 via the amplifier circuit 32, the normally open relay contact 37a is closed, and the IM6 is reversed. Therefore, meat box 3
moves in the opposite direction, that is, in the direction of returning to the front position. Furthermore, since the Q output signal q of the D flip-flop 16 is at logic "H", the AND circuit 22 accepts the detection signal d from the detector 14. Therefore, when the operating switch 10 is turned on once and the detector 14 detects that the meat box 3 moves in the opposite direction and reaches the front stop position, the detection signal d passes through the AND circuit 22 and is output to the OR circuit. The signal is input to the circuit 19. In this case, an overload condition of IM6 is detected,
Since the power supply to the motor has been cut off, the Q output signal O of the D flip-flop 15 is at logic "L".
, and the AND circuit 23 causes the detector 13 to
Since the detection signal c of is blocked, OR circuit 1
At 9, the detection signal d of the detector 14 is selected. Therefore, the OR circuit 19 outputs one logic "H" pulse output signal e as shown in FIG. 4e. This logic "H" output signal e is input to the D flip-flop 16 via the OR circuit 20,
The D flip-flop 16 is cleared, and the Q output signal q is inverted from logic "H" to logic "L" as shown in FIG. 4q. Therefore, relay coil 3
The excitation of IM 7 is stopped, the normally open relay contact 37a is closed, and the power supply to IM 6 is cut off. Below is (1)
As in the case of item 1, the output signal p of the timer ₂₅ is set to logic "H" for a time T2 at the falling edge of the signal that inverts the output signal e of the OR circuit 19 from logic "H" to logic "L", and this Amplifying circuit 3 by output signal p
3, the relay coil 38 is energized, the normally open relay contact 38a is closed, and the trigger circuit 35 is activated, firing the thyristor 34 for a time T ₂ . Therefore, a braking current flows through the IM 6, and the meat box 3 stops at the front stop position. Further, the clear circuit 27 is activated at the fall of the output signal p of the timer 25,
The clear circuit 27 outputs a logic "H" pulse output signal r for a short time as shown in FIG. .

In short, in the above explanation, the D flip-flop 15, the amplifier circuit 31, the relay coil 36, and the normally open relay contact 36 constitute a normal rotation drive circuit, and the D flip-flop 16, the amplifier circuit 32
The relu coil 37 and the normally open relay contact 37a constitute a reverse drive circuit, and the current detector 28 and voltage conversion circuit 29 constitute a load detector.
Comparator 30, AND circuit 21, timer 26
and D flip-flop 17 constitute a comparison circuit, detectors 13 and 14 constitute a position detector, timer 25, amplifier 33, and relay coil 3.
8. The normally open relay contact 38a, the thyristor 34, and the trigger circuit constitute a braking circuit.

According to the embodiment of the present invention described above, when the IM 6 is driven in the forward direction, the detector 13 detects that the meat box 3 has reached the near stop position, and when the IM 6 is driven in the reverse direction, the meat box 3 has reached the near stop position. Since this is detected by the detector 14 and the braking circuit is driven, the meat box 3 can be accurately stopped at the front stop position both during forward rotation and reverse rotation.

In addition, the load current of the electric motor during meat cutting work is detected, and if the overload condition continues for a predetermined time T ₂ or more, the power supply to the electric motor is automatically cut off. Even if the electric motor is in a restrained state, burnout of the electric motor can be prevented, and the safety of the meat cutting operation can be improved.

In addition, by operating the operation switch 10,
When the IM6 is reversed to move the meat box 3 back to the front position and the front stop position is reached,
Since the IM 6 can be braked to accurately stop the meat box 3 at the front stop position, the meat cutting operation can be resumed promptly.

In the above embodiment, the load current of the IM6 is detected, but the load current of the electric motor for rotating the cutter may also be detected.Furthermore, two current detectors are provided to detect the load current of the IM6 and the cutter. The load current of the rotating electric motor may be detected, and if either current detector detects an overload condition, the normally open relay contact 36a may be opened via a comparison circuit to stop the electric motor.

In addition, the current detector 28 is used to detect the overload state, but the rotation speed of the cutter 8, the moving speed of the meat box 3, the rotation speed of the cutter rotating electric motor or IM 6, or the rotation speed of the belt or reducer 7 can be detected. The load state may be detected by detecting a change.

In addition, in order to detect the front stop position of the meat box 3,
Although the detectors 13 and 14 are provided separately, they may be integrated into one detector.

Furthermore, after the forward rotation drive circuit becomes inoperable, the operation switch 10 is operated to operate the reverse rotation drive circuit. The operation starts with a signal that inverts the logic from logic "L◎" to logic "H", and after a certain period of time, the logic changes to "L".
It is also possible to connect a timer that changes to logic "H" from the D flip-flop 16 to the T terminal of the D flip-flop 16 to automatically operate the reverse drive circuit.

As explained above, according to the present invention, the reverse operation is easy and the meat box can be accurately stopped at the front stop position, thereby increasing safety during cutting of meat loaves. There is an effect.

[Brief explanation of the drawing]

Fig. 1 is a schematic front view showing an embodiment of the meat cutting machine of the present invention, Fig. 2 is an explanatory view showing the arrangement of an embodiment of the meat box position detection section of Fig. 1, and a is a plan view. ,b
1 is a front view, FIG. 3 is a block diagram showing an embodiment of the control circuit of the meat cutter of the present invention, and FIG. 4 is a time chart of signals of various parts in FIG. 3...meat box, 6...meat box driving electric motor, 7...
Reducer, 8...Cutter, 9, 10...Operation switch, 11...Meat box position detector, 12...Protrusion piece,
13, 14...Detector, 15-17...D flip-flop, 18-20...OR circuit, 21-2
3...AND circuit, 24...Inverter circuit, 2
5, 26...Timer, 27...Clear circuit, 28
...Current detector, 29...Voltage conversion circuit, 30...
...Comparator, 31-33...Amplification circuit, 34
...Thyristor, 35...Trigger circuit, 36-3
8... Relay coil, 36a to 38a... Normally open relay contact.

Claims (1)

[Claims for Utility Model Registration] 1. A meat box is reciprocated by the rotation of an electric motor via a speed reducer and a crank mechanism, and the meat loaf stored in the meat box is cut by a rotary knife. , a meat cutter equipped with a braking circuit that stops the meat box at the operator's side position when the cutting operation is finished, wherein the electric motor is a reversible motor capable of forward and reverse rotation; a drive circuit, a reversing drive circuit for reversing the electric motor, a load detector for detecting an overload on the electric motor during cutting of the meat when the forward rotation drive circuit is operating; and the load detector. a comparison circuit that receives a detection signal from the controller and compares the magnitude of whether or not the load condition is equal to or higher than a preset load condition, and sends out an output signal when the load condition is equal to or higher than the preset load condition; an overload control circuit that sometimes stops the operation of the forward rotation drive circuit; a position detector that detects when the meat box has reached a front stop position when the electric motor rotates forward and reverse; and the forward rotation drive circuit. motor reversing drive means for operating the reversing drive circuit to reverse the motor when the motor is stopped by the overload control circuit; and the meat box reaches the front stop position by reversing the motor. A detection signal when the position detector detects that the meat box is stopped at the forward stop position is used to stop the operation of the reverse drive circuit and operate the braking circuit that brakes the electric motor. A meat cutting machine characterized by comprising a meat box stop control means. 2. The meat cutter according to claim 1, wherein the electric motor reverse drive means is configured to operate when an operation switch is operated. 3. The meat cutter according to claim 1, wherein the electric motor reverse drive means is configured to automatically operate after a predetermined time when the overload control circuit causes the forward rotation drive circuit to operate. Machine.