JP2011169678A - Hopper and weighing instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hopper holding articles by closing a gate member and dropping and discharging the held articles by opening and operating the gate member, which discharges the held articles while restraining them from dispersing in upper and lower directions. <P>SOLUTION: The instrument includes a fall acceleration means working along with the opening and operating of the gate member 18 and providing downward acceleration to the articles w falling. The fall acceleration means is set so that the falling articles w are press accelerated at a speed higher than the velocity of free fall by the gate member 18 moving downward. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hopper that receives and holds an article, and then operates to release and drops the held article, and a weighing device including the hopper.

  As an example of a weighing device, for example, as shown in Patent Document 1, a combination weigher is known that performs combination weighing so that an article that is an object to be weighed such as confectionery is within a predetermined weight range.

JP 2009-92399 A

  In the combination weigher, the articles weighed in combination so as to be within a predetermined weight range are generally put into a packaging machine and packaged. In the combination weigher, the weighed articles are once collected into a collecting hopper. Then, based on the instruction from the packaging machine, the collecting hopper is opened, the articles are discharged downward, the discharged articles are charged into the packaging bag of the packaging machine, and the packaging bag is sealed by heat sealing or the like. The packaging is completed with the stop treatment.

  In this case, the processing cycle of the entire weighing and packaging machine requires the weighing processing time required to weigh the articles and temporarily hold them in the collecting hopper, and the filling and holding of the articles held with the collecting hopper opened. The filling process time and the sealing process time of the packaging bag are added, and the weighing process and the sealing process are speeded up by various developments.

  However, the filling process into the packaging bag allows the articles to freely fall from the collecting hopper, and therefore, when an article that is somewhat bulky and has a low density, for example, an article such as a marshmallow, is to be treated. As shown in FIG. 4, when a large number of articles w held in the collecting hopper 40 are dropped and discharged, the articles w are scattered long and fall under the influence of air resistance or the like even if the collecting hopper 40 is opened at high speed. Therefore, it takes time for all articles w from the head to the tail to be filled in the packaging bag, so that the filling processing time becomes longer, and the processing cycle of the entire weighing and packaging machine becomes longer. It was.

  In addition, the conventional hopper is driven in a synchronized manner by a complicated opening / closing drive mechanism using a link mechanism, a return spring, etc., as opposed to a pair of opposed gate members. It also took time to clean.

  The present invention has been made by paying attention to such a situation, and provides a hopper that can discharge an article once held with less fluctuation up and down, and a weighing device using the hopper. Is the main purpose. Another object of the present invention is to simplify the drive mechanism that controls opening and closing of the hopper to facilitate operation adjustment and cleaning.

  In order to achieve the above object, the present invention is configured as follows.

 (1) The hopper of the present invention is a hopper that closes the gate member and holds the article so as not to fall downward, opens the gate member, drops the held article downward, and discharges the article. When the article is dropped downward by opening the gate member, a drop accelerating means for accelerating the dropping speed is provided.

  According to the hopper of the present invention, the article that falls due to the opening of the gate member is forcibly accelerated by the fall accelerating means so as to be higher than the free fall speed. Even if it is an easy-to-receive article, it is less likely to be scattered up and down for a long time so that it can be dropped and discharged together.

 (2) In a preferred embodiment of the hopper according to the present invention, the drop acceleration means is a member that moves the falling article downward and presses and accelerates downward from above at a higher speed than its free fall speed.

  The downward moving member only needs to be able to press and accelerate the falling article, and may be one that moves directly downward or obliquely downward, or one that rotates downward.

  According to this embodiment, an article that falls by opening the gate member can be forcibly and accurately accelerated by a member that moves downward at high speed, and even an article that is susceptible to air resistance at the time of dropping can be vertically moved up and down. There are fewer things that can be scattered for a long time and they can be discharged together.

 (3) In the embodiment of the above (2), a rotary gate that is intermittently rotated around a horizontal axis is provided, and the rotary gate is a plurality of gates arranged at different angles in the rotation direction. The gate member is received and held by the gate member in the rotation stopped state, and the gate member receiving and holding the article is released with the rotation of the rotary gate, and the gate member positioned at the top of the rotation is dropped. The article may be pressed and accelerated.

  The rotation gate may be singular or plural. When there is a single rotating gate, it is preferable to provide a member having a holding surface that can receive and hold an article between the rotating gate and the gate member.

  According to this embodiment, since the gate member is opened and closed and the acceleration discharge operation is performed simply by intermittently driving the rotary gate, the hopper opening and closing drive mechanism is relatively simple and simply transmits the rotation. In addition, the operation adjustment can be as simple as adjusting the rotational phase, and it is easy to remove and clean the rotary gate.

  Further, since the gate member is used as both a member for receiving and holding the article and a member for pressing and accelerating the article, for example, a gate member for receiving and holding the article and a member for pressing and accelerating the article are separately provided. Therefore, the structure can be simplified compared with the case of interlocking.

 (4) In the embodiment of the above (3), the pair of rotating gates are arranged opposite to each other, and the rotating gates are intermittently rotated inwardly in synchronization with each other so that the rotating gates in the stopped state are opposed to each other. The gate member may receive and hold the article.

  According to this embodiment, since a space for receiving and holding the article is formed between the pair of rotary gates, for example, the article is used as compared with the case where a single rotary gate is used to perform the same function. Each rotating gate can be made small while ensuring a sufficient volume of the holding space, and it becomes easy to drive the rotating gate at high speed with less air resistance.

 (5) In the above embodiment (3) or (4), the rotary gate may be rotationally driven via a Geneva mechanism so that the initial stage and the final stage are low speed and the middle stage is high speed.

  According to this embodiment, desired acceleration can be imparted to the article in a high speed range, and it is easy to stop the article at the reference standby position with high accuracy. In addition, since the Geneva mechanism is used, the rotary gate can be easily rotated intermittently at an unequal speed without speed control of a drive source such as a motor.

 (6) The weighing device of the present invention includes the hopper according to the present invention.

  The hopper may be capable of weighing the object to be weighed in addition to temporarily holding and discharging the object to be weighed.

  According to the weighing device of the present invention, even a group of articles that are easily subjected to air resistance at the time of dropping can be discharged from the hopper together with little dispersion up and down.

 (7) In a preferred embodiment of the weighing device according to the present invention, the hopper is a collecting hopper that once holds the weighed articles and then drops and discharges them to the packaging machine.

  According to this embodiment, even a group of articles that are susceptible to air resistance at the time of dropping can be discharged together with little dispersion up and down, and accordingly, the filling processing time of the articles discharged from the collecting hopper to the packaging machine As a result, the processing cycle from weighing to completion of packaging in the weighing device can be shortened, and this is effective in improving the efficiency of weighing and packaging.

  As described above, according to the present invention, there is provided a hopper that can discharge a held article in a short time without being scattered up and down, and a weighing device that includes such a hopper and can process with high efficiency. can do.

FIG. 1 is a front view of the weighing and packaging machine. FIG. 2 is a perspective view of the combination weigher. FIG. 3 is a cross-sectional plan view of the hopper. FIG. 4 is a longitudinal front view of the hopper. FIG. 5 is a perspective view of the hopper. FIG. 6 is an explanatory diagram of the operation of the hopper. FIG. 7 is a diagram showing another hopper driving mechanism. FIG. 8 is a cross-sectional plan view showing a hopper according to another embodiment of the present invention. FIG. 9 is a front view showing a drive mechanism of the hopper of FIG. FIG. 10 is an operational characteristic diagram of the hopper of FIG. FIG. 11 is an operation explanatory diagram of a conventional hopper.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 shows an overall front view of a weighing and packaging machine to which the present invention is applied, and FIG.

  This weighing and packaging machine, for example, wraps an article as an object to be weighed such as confectionery by performing combination weighing so as to be within a predetermined weight range, and is assembled in a bowl shape that allows an operator to go up and down. A combination weigher 2 is installed at the upper part of the standing frame 1, and a weighed object is put into a supply chute 4 of a packaging machine 3 installed at the lower part and packed into a bag. Articles conveyed from a production line or the like are lifted from the downstairs by a bucket lifter 5 and supplied to the combination weigher 2 from above.

  On the floor of the frame 1, a floor portion 6 having an opening at the center is provided, and the combination scale 2 is installed on the floor so as to face the opening.

  As shown in FIG. 2, the combination weigher 2 has a substantially cylindrical center base body 7 supported at the center by four legs 9 attached to a base 8, and a bucket lifter 5 on the upper part thereof. A conical dispersion feeder 10 is provided that disperses the articles dropped and supplied from the terminal end of the article radially by vibration. Around the dispersion feeder 10, there are provided a plurality of linear feeders 12 for feeding the objects to be weighed and transferred to the supply hoppers 11 by vibration. Below each linear feeder 12, a supply hopper 11 and a weighing hopper 13 are provided correspondingly, and the plurality of supply hoppers 11 and the weighing hoppers 13 are arranged in a circle around the center base body 7.

  The dispersion feeder 10, the linear feeder 12, the supply hopper 11, and the weighing hopper 13 are attached to the center base 7, and the vibration device for the dispersion feeder 10 and the linear feeder 12, the gate opening / closing device for the supply hopper 11 and the weighing hopper 13, etc. The drive unit is housed in the center base body 7. Each weighing hopper 13 is provided with a weight sensor (not shown) such as a load cell for measuring the weight of an object to be weighed in the weighing hopper 13, and this weight sensor is also housed in the center base body 7 together with the drive unit. Has been.

  Below the weighing hoppers 13 arranged in a circle, a collecting chute 14 for collecting articles discharged from a plurality of weighing hoppers 13 combined in a predetermined weight range is arranged. Below 14, a collecting hopper 15 is disposed for receiving and storing articles that have slipped from the collecting chute 14 and then dropping and discharging them toward the chute 4 of the packaging machine 3.

  In the hopper according to the present invention, the collective hopper 15 is configured as follows.

  3 is a transverse plan view of the collective hopper 15, FIG. 4 is a longitudinal front view of the collective hopper 15, and FIG. 5 is a perspective view of the collective hopper 15.

  The collective hopper 15 includes a pair of left and right rotary gates 16 arranged to face each other so as to be rotatable around a horizontal axis, and a drive device 17 that rotationally drives them.

  Each rotary gate 16 has a plurality of (three in this embodiment) gate members 18 formed in a plate blade shape and is radially arranged at an equal pitch (120 ° pitch in this example) in the rotation direction. A side plate 19 is provided in front of and behind the gate member 18 to prevent the supplied article w, which is an object to be weighed, from spilling back and forth. It is connected with the rotation spindle 20 projected from the right and left so that attachment or detachment is possible.

  The driving device 17 transmits the rotational power of the stepping motor 21 that is rotationally controlled in a fixed direction by a control device (not shown) to the rotational support shaft 20 of each rotational gate 16 and synchronizes both rotational gates 16. It is configured to be rotationally driven inward from each other. More specifically, the power extracted from the output shaft 22 of the stepping motor 21 is transmitted to one rotary support shaft 20 via gears 23 and 24 having the same diameter, and the power extracted by branching from the output shaft 22 is the same. The gears 25 and 26 having a diameter and a reverse gear 27 are transmitted to the other rotary support shaft 20 in the opposite direction.

  In a state in which the rotary gate 16 is stopped, as shown in FIG. 4, the gate members 18 in both rotary gates 16 are in an article receiving posture in which they face each other inward and face each other, and the gate is positioned at the top of the rotation. Each of the members 18 is in a standing posture, and the remaining gate members 18 are in an outward standby posture, and an upper collective chute is disposed between the gate member 18 in an article receiving posture and the gate member 18 in a standing posture. The article w supplied from 14 is received and held so as not to fall downward.

  In addition, the slit 28 is formed in the free end of each gate member 18, and when the gate members 18 which face and face each other cross | intersect, interference is avoided. The opening width of the slit 28 is set narrow so that the article does not fall downward.

  When the articles weighed in combination and temporarily held in the collecting hopper 15 are discharged to the packaging machine 3, the stepping motor 21 is rotated and activated in a predetermined direction from the stop state shown in FIG. As the stepping motor 21 is actuated, the two rotary gates 16 are rotated inward from each other, and the pair of gate members 18 that receive and hold the article w so as not to fall downwardly open and move the article w downward. While being dropped and discharged downward, the gate members 18 in the standing posture each move inward and downward.

  The stepping motor 21 is configured to detect the rotation angle of the output shaft 22 using a rotary encoder (not shown) and the rotation stops when it is detected that the output shaft 22 has rotated 120 ° from the stop phase. And the gate member 18 in the article receiving posture is switched to the outward standby posture, and the gate member 18 in the standing posture is switched to the article receiving posture inclined downward inwardly. The gate member 19 that has been in the outward standby posture is in a standing posture, and the position of the gate member 18 is sequentially switched with the intermittent rotation of the stepping motor 21 by a predetermined angle (120 °). The stepping motor 21 is pulse-controlled, and the speed is controlled so as to rotate at a low speed in the initial stage and the final stage of rotation and to rotate at a high speed in the meantime.

  Here, the rotation speed of the stepping motor 21 is set so that the free end portion moving speed in the rotation region excluding the initial rotation and the final rotation of the gate member 18 is larger than the free fall speed of the article w. As shown in FIG. 6 (b), the article w group that falls by opening the gate is forcibly pressed downward at a speed higher than the free fall speed by the gate member 18 that rotates downward from the standing posture. Are discharged in a downward direction at a time. The gate member 18 that presses and accelerates the falling articles w group in this way constitutes fall acceleration means.

When the length of the gate member 18 from the rotation axis is r [m] and the angular velocity of the gate member 18 is ω [rad / s], the acceleration a [m / s ² ] at the tip of the gate member 18 is a = r · ω ² If the value of the acceleration a exceeds the gravitational acceleration g = 9.8 [m / s ² ], the article w can be pressed and accelerated by the downward rotation of the gate member 18.

  Here, for example, if the length of the gate member 18 is r = 0.09 [m], the angular velocity ω at which a> g becomes ω> 10.4 [rad / s]. If the gate member 18 is rotated 120 ° (= 2π / 3 [rad]) at 0.2 [s], ω = 10.5 [rad / s] and the above condition a> g is satisfied. be able to.

  If actually operated under the above conditions, ω <10.5 [rad / s] in the rotation start region and rotation stop region, and ω ≧ 10.5 [rad / s] in the other rotation regions, the article w The gate member 18 can be pressed and accelerated.

  In this way, by pressing and accelerating the article w so that the article w is not scattered vertically and dropped and discharged, the time from the start of discharging until the packaging machine 2 is filled is long in the vertical direction of the article w. Compared to the conventional case (see FIG. 11) where the free fall is discharged, the processing cycle of the entire weighing and packaging machine is shortened accordingly.

  In the above-described embodiment, the rotational power of the stepping motor 21 is transmitted to the rotary support shaft 20 of each rotary gate 16 via a gear mechanism. However, as another embodiment of the present invention, for example, as shown in FIG. Further, a toothed motor pulley 50 is fixed to the output shaft 22 of the stepping motor 21, and a toothed belt 53, between the motor pulley 50 and the driven pulleys 51, 52 of the rotation support shaft 20 of each rotation gate 16 is provided. 54 may be suspended, and the rotational power of the stepping motor 21 may be transmitted to the rotary spindle 20 of each rotary gate 16 via the toothed belts 53 and 54, respectively. In this case, the toothed belt 54 is crossed between the motor pulley 50 and the driven pulley 52 of the rotation support shaft 20 of one of the rotation gates 16, that is, the toothed belt is twisted so as to intersect at the center. They are connected in a cross shape and rotated in the opposite direction.

(Embodiment 2)
8 to 10 show another embodiment in which the driving device 17 of the collective hopper 15 is modified.

  In this embodiment, the rotational power of the stepping motor 21 is first transmitted to the Geneva mechanism 30 that is an inconstant speed transmission mechanism, and the speed changing power is transmitted to the rotary shafts 20 through the gears 23, 24, It is transmitted via the gears 25 and 26 and the reverse gear 27.

  The Geneva mechanism 30 includes a driving wheel 31 connected and fixed to the output shaft (drive shaft) 22 of the stepping motor 21 and a Geneva wheel 33 connected and fixed to a driven shaft 32 provided separately. In the Geneva wheel 33, four drive grooves 34 are formed radially, and a partial arc-shaped recess 35 is formed between the drive grooves 34. On the other hand, the driving wheel 31 is accompanied by the rotation of the wheel. A drive pin 36 that engages and disengages with the drive groove 34 and an arc portion 37 that engages with the recess 35 are provided. When the stepping motor 21 is stopped and the drive pin 36 is in the reference standby position, the arc portion 37 is engaged with the recess 35 and the drive pin 36 is detached from the drive groove 34.

  When the stepping motor 21 is started to rotate in a predetermined direction from the reference standby state and the driving wheel 31 is rotated at a constant speed, a predetermined angle phase (45 °) until the drive pin 36 is engaged with the drive groove 34 is obtained. The Geneva wheel 33 is maintained in a fixed posture. When a predetermined angle phase (45 °) is passed, the drive pin 36 engages with the drive groove 34 and the Geneva wheel 33 is driven to start rotating. As the rotation of the driving wheel 31 proceeds, the drive pin 36 moves inward of the driving groove 34, the transmission ratio between the driving wheel 31 and the Geneva wheel 33 changes, and the driving wheel 31 rotates at a constant speed. On the other hand, the Geneva wheel 33 is rotated at unequal speed. When the driving wheel 31 reaches a predetermined angle phase (135 °), the Geneva wheel 33 is rotated by 90 ° to disengage the drive pin 36 from the drive groove 34 and the arc portion 37 is engaged with the next recess 35. First, the Geneva wheel 33 is maintained in the stopped state again with respect to the subsequent rotation of the driving wheel 31. Even after the Geneva wheel 33 stops, the rotation of the driving wheel 31 continues, and when the drive pin 36 reaches the original reference position, the stepping motor 21 stops and returns to the reference standby state to prepare for the next operation. .

  Here, while the Geneva wheel 33 is rotated, the drive pin 36 moves from the outer end to the inner end of the drive groove 34 and then moves to the outer end again. Therefore, the driven shaft 32 provided with the Geneva wheel 33. 10 changes with the characteristics shown in FIG. 10, and the Geneva wheel 33 rotates at a low speed in the initial stage, rotates at a high speed in the middle period, and rotates again at a low speed in the final period. Thus, the gate member 19 can be rotated faster than the free fall speed of the article w without the stepping motor 21 being rotated at a particularly high speed. Moreover, compared with the said embodiment, the state which has stopped the rotation gate 16 and hold | maintained goods can be maintained reliably.

  In this example, since the driven shaft 32 of the Geneva wheel 33 is rotated 90 ° by one operation, the rotary support shaft 20 is rotated 120 °, so that the driven shaft 32 is rotated. It is necessary to increase the speed and transmit the gears to the respective rotation support shafts 20.

(Other embodiments)
The present invention can also be implemented in the following forms.

  (1) In the above embodiment, the pair of rotary gates 16 provided with the three gate members 18 are intermittently rotated inwardly by 120 ° each other, but the two gate members 18 are placed at diagonal positions. It is also possible to implement in a form in which the deployed rotary gate 16 is intermittently rotated by 180 °.

  (2) In the above embodiment, the slit 28 is formed at the free end of each gate member 18 so as not to interfere when the opposing gate members 18 cross each other. The opposing gate members 18 may be arranged close to each other so as not to cross each other, and the slit 28 may be omitted. In this case, as in the above-described embodiment, the gate members 18 of the two rotating gates 16 do not receive and hold the article in a posture in which the gate members 18 of the two rotating gates 16 are inclined downward inward. What is necessary is just to make it hold | maintain and hold | maintain articles | goods in the attitude | position facing each other and facing, ie, a horizontal state.

  (3) In the above embodiment, the pair of rotary gates 16 are intermittently rotated inward from each other. However, the gate member is opposed to the single rotary gate 16 and the gate member 18 of the rotary gate 16. It is also possible to use a fixed guide plate or the like having a holding surface that can receive and hold the article.

  (4) In the above embodiment, the gate member 18 that receives the article w is also used as a member that accelerates and presses the article w. However, a gate member that simply swings and opens and a dedicated member that presses and accelerates the article are separated. It is also possible to deploy to.

  The present invention is useful for hoppers of various apparatuses.

15 Collecting hopper 16 Rotating gate 18 Gate member 30 Geneva mechanism w Article

Claims (7)

A hopper that closes the gate member and holds the article so as not to fall downward, opens the gate member, drops the held article downward, and discharges the article,
A hopper comprising drop accelerating means for accelerating a dropping speed when the held article is dropped downward by opening the gate member.   2. The hopper according to claim 1, wherein the drop accelerating means is a member that moves the falling article downward and presses and accelerates downward from above at a higher speed than its free fall speed. Comprising a rotary gate that is intermittently driven to rotate around a horizontal axis;
The rotating gate has a plurality of gate members arranged at different angles in the rotating direction,
When the rotation is stopped, the gate member receives and holds the article, and the gate member receiving and holding the article is released along with the rotation of the rotary gate, and the fallen article is pressed and accelerated by the gate member positioned at the top of the rotation. The hopper according to claim 2.   4. The pair of rotary gates are arranged opposite to each other, and the rotary gates are synchronously intermittently rotated inward from each other, and the articles are received and held by the gate members facing and opposed to each other in both rotary gates in a stopped state. The hopper described in 1.   The hopper according to claim 3 or 4, wherein the rotary gate is rotationally driven through a Geneva mechanism so that the initial stage and the final stage are low speed and the middle stage is high speed.   A weighing apparatus comprising the hopper according to any one of claims 1 to 5.   The weighing device according to claim 6, wherein the hopper is a collecting hopper that once holds a weighed article and then drops and discharges it to a packaging machine.

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