JP2013096738A - Hopper opening/closing mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hopper opening/closing mechanism capable of closing a gate of a hopper by a simple constitution without using a spring.SOLUTION: The hopper opening/closing mechanism includes: a drive control part 3 for applying force to a discharge gate 14A so as to open the discharge port in a scale hopper 14 including a scale hopper body part 14B formed with the discharge port for discharging an article on its bottom and the discharge gate 14A rotatably joined to the scale hopper body part 14B to open/close the discharge port; a toggle arm 25 allowed to be rotated by receiving force applied from the drive control part 3; and a link 26 of which one end is rotatably joined to the discharge gate 14A and the other end is rotatably joined to the toggle arm 25 to transmit the force applied from the toggle arm 25 to the discharge gate 14A. Force is applied to the discharge gate 14A to close the discharge port by torque generated around a rotational axis by tare weight of the toggle arm 25 and torque generated around the rotational axis by tare weight of the discharge gate 14A.

Description

  The present invention relates to a combination weigher that performs a combination calculation based on the weight of each of the articles supplied in a distributed manner and obtains a combination in which the total weight of the articles is a value within an allowable range with respect to a target weight. In particular, the present invention relates to a hopper opening / closing mechanism provided for each supply destination of the article in order to hold the supplied article.

  A combination weigher has been put into practical use in which objects to be weighed are distributedly supplied to a plurality of weighing hoppers, each weight value is weighed, and a combination in which the added value of the weight values is closest to the target weight is obtained. This combination weigher discharges and collects the objects to be weighed from the weighing hopper that is the combination closest to the target weight, and can pack them, for example.

  Such a combination weigher is configured such that the lower opening portion of the hopper body that is open at the top and bottom can be opened and closed by a gate that is rotatably attached to the hopper body. As an opening / closing mechanism for enabling the gate attached to the hopper body to be opened / closed, for example, a link mechanism 110 in which the gate G1 is connected to an L-shaped arm 115 via a link 114 as shown in FIG. Is used. FIG. 8 is a diagram showing a configuration of a gate opening / closing mechanism in the conventional weighing hopper 111.

  As shown in FIG. 8, a pair of connection frames 113 extending toward the base body (main body) side of the combination weigher are fixed to both side surfaces of the hopper main body 112 of the weighing hopper 111. The arm 115 is rotatably attached to one of the connection frames 113 by an arm coupling portion 116. A bar is horizontally placed between the pair of connecting frames 113 in the horizontal direction. The weighing hopper 111 can be detachably attached to the base of the combination weigher by hooking this bar on a hanger provided on the side of the base of the combination weigher.

  The link 114 is rotatably joined to the arm 115 by the second link fulcrum 117b at one end, and is joined to the gate G1 by the first link fulcrum 117a at the other end. A so-called toggle mechanism is formed by connecting the arm 115 and the gate G1 via the link 114. When the gate G1 is closed in the weighing hopper 111, the closed state of the gate G1 is maintained by the function of the toggle mechanism.

  Further, as shown in FIG. 9, a spring 119 is provided between the connecting frame 113 and the arm 115, and when the measuring hopper 111 is closed, the gate is closed by the restoring force of the spring 119, and this closed state is maintained. Weighed hoppers are also used. FIG. 9 is a diagram illustrating a configuration of a gate opening / closing mechanism of a weighing hopper according to the related art.

  More specifically, in the weighing hopper with a spring as shown in FIG. 9, the gate of the weighing hopper is opened and closed by a drive lever provided in an actuator unit (not shown). That is, the drive lever and the arm 115 are engaged, and the arm 115 rotates by a predetermined angle around the rotation axis of the arm coupling portion 116 according to the rotational movement of the drive lever.

  When the end of the arm 115 (the end on the side joined to the link) moves clockwise from the lower position to the upper position (clockwise) around the rotation axis of the arm coupling portion 116, the arm 115 is joined. The end portion of the link 114 on the side being moved is moved upward in accordance with this movement, and the link end portion on the side joined to the gate is also raised. As a result, the gate is pulled up counterclockwise around the rotation axis of the gate coupling portion 118, and the gate is opened. Further, when the gate is opened, a spring 119 provided between the connecting frame 113 and the arm 115 is deformed by applying a force by the movement of the arm 115.

  On the contrary, the arm 115 moves from the upper position to the lower position counterclockwise (counterclockwise) with its end (the end connected to the link) centered on the rotation axis of the arm coupling portion 116. Then, the end of the link 114 on the side joined to the arm 115 is moved from the upper position to the lower position in accordance with this movement. When the end of the link 114 on the side joined to the arm 115 moves in this way, the end of the link 114 on the side joined to the gate is also pulled down. As a result, the gate moves clockwise around the rotation axis of the gate coupling portion 118 downward. In this movement, in addition to the force exerted by the drive lever of the actuator unit, the restoring force of the spring 119 deformed when the gate is opened acts. Further, when the gate is closed, a force is applied so that the closed state is maintained by the restoring force, and the gate is held in a closed state by a toggle mechanism formed by the link 114 and the arm 115.

  Thus, the weighing hopper with a spring can use the restoring force of the spring 119 even when the closed state is maintained. For this reason, it is not necessary to apply a force from the drive lever of the actuator unit so that the gate does not open, and it is easy to cut the edge between the weighing system for weighing the weighing hopper and the driving system for opening and closing the gate. Can do. In addition, the gate can be quickly closed by the restoring force of the spring 119.

  However, in the weighing hopper with a spring, the operation pattern of the drive lever is restricted by the spring 119, so that the degree of freedom is low. Furthermore, since the gate closes at a high speed due to the restoring force of the spring 119, there is a problem that the impact sound when the gate is closed is loud. In addition, the measuring hopper with a spring has a problem such as damage due to metal fatigue of the spring 119. In particular, if the spring 119 is broken and mixed into an object to be weighed, it becomes a very big problem.

  Therefore, a combination weigher has been developed in which a spring 119 is not provided on a component attached to the weighing hopper (for example, Patent Document 1). The combination weigher disclosed in Patent Document 1 is provided between a supply hopper drive unit and a drive lever, and a biasing spring is provided in a weighing hopper drive unit side link mechanism that connects them. In this combination weigher, when the engaged portion provided in the weighing hopper drive unit side link mechanism and the engaging portion provided in the drive unit shift from the disengaged state to the engaged state, the engaging portion is engaged. The engaged portion is configured to be urged in a direction toward a predetermined position so that the engaged portion can be engaged. In addition, the combination weigher disclosed in Patent Document 1 is also configured so that the hopper gate can be maintained in a closed state using a toggle mechanism.

JP-A-5-162787

  However, the conventional technology as described above has a problem that the gate of the hopper cannot be closed with a simple configuration without using a spring.

  More specifically, in Patent Document 1, since a spring is not used for the structure attached to the hopper, for example, it is possible to prevent a problem that the spring is broken and mixed into an object to be measured. However, the structure of the link mechanism (weighing hopper drive unit side link mechanism) provided between the drive unit and the drive lever is complicated, and is difficult to apply to, for example, a small combination weigher.

  The present invention has been made in view of the above-described problems, and an object thereof is to realize a hopper opening / closing mechanism capable of closing a hopper gate with a simple configuration without using a spring. It is in.

  In order to solve the above-described problems, the hopper opening / closing mechanism according to the present invention performs a combination calculation based on the weight of each of the articles supplied in a distributed manner, and the total weight of the articles is within a tolerance range with respect to the target weight. In a combination weigher for obtaining a combination, a hopper opening / closing mechanism provided for each supply destination of the article to hold the supplied article, wherein the hopper has a discharge port for discharging the supplied article. It has a container main body formed on the bottom surface and a gate that is rotatably joined to the container main body for opening and closing the discharge port, and applies a force to the gate so as to open the discharge port. A driving unit, an arm unit that rotates by receiving a force acting on the driving unit, one end rotatably joined to the gate, and the other end rotatably joined to the arm unit, and a force acting from the arm unit The And a link portion that transmits to the gate, and closes the discharge port by torque generated around the rotation axis of the arm portion due to its own weight and torque generated around the rotation axis of the gate due to its own weight. A force is applied to the gate.

  Here, in the combination weigher, as a hopper provided for each supply destination of the article in order to hold the supplied article, for example, a distributed supply article is accommodated, and the weight of each article is measured. There is a weighing hopper used for this purpose. Further, a supply hopper that is provided corresponding to each weighing hopper, temporarily holds the supplied article, and puts the article into the weighing hopper at a desired timing.

  According to the configuration described above, the hopper can open and close the housing main body portion by rotating the gate that is rotatably joined to the housing main body portion.

  Here, since the opening / closing mechanism of the hopper according to the present invention includes the drive unit, the arm unit, and the link unit, when the gate is operated so as to open the discharge port, the force applied from the drive unit is applied to the arm unit. A force can be applied to the gate so as to open the discharge port of the receiving main body portion through the receiving portion and the link portion. That is, it can be controlled so that the gate is opened by the driving unit.

  In addition, when the gate is operated so as to close the discharge port, the gate is closed by the torque around the rotation axis generated by the weight of the arm portion and the torque around the rotation axis generated by the weight of the gate. Force can be applied to For this reason, without using the restoring force of the spring as in the conventional combination weigher, and without having a complicated structure such as providing a new member separately in the link mechanism for opening and closing the gate, The gate can be operated to close.

  Therefore, the opening / closing mechanism of the hopper according to the present invention has an effect that the gate of the hopper can be closed with a simple configuration without using a spring.

  In the hopper opening / closing mechanism according to the present invention, in the above-described configuration, the gate and the arm portion are shifted from the respective rotation axes so that the respective centers of gravity rotate in a direction in which the gate closes the discharge port. You may be comprised so that it may become.

  According to the configuration described above, the center of gravity of the gate and the rotation axis of the gate do not coincide with each other and are shifted. Further, the center of gravity of the arm portion and the rotation axis of the arm portion do not coincide with each other and are shifted. As described above, the rotation axis of the gate and the rotation axis of the arm part and the center of gravity of each of the gate and the arm part do not coincide with each other and deviate from each other. Resulting in.

  Further, the position of the center of gravity of each of the gate and the arm is determined so as to exert a force on the gate so that the gate rotates in the direction of closing the discharge port. For this reason, torque is generated around each rotation axis by rotating the gate and the arm part, and the generated torque can rotate the gate in the direction of closing the discharge port.

  In the hopper opening / closing mechanism according to the present invention, in the above-described configuration, the gate has a first center of gravity adjustment portion for adjusting the position of the center of gravity so as to rotate with respect to the housing portion main body in the closing direction of the gate. And a second center of gravity adjustment unit for adjusting the position of the center of gravity so that the arm unit rotates so as to apply a force to rotate the housing unit in the closing direction of the gate. It may be provided.

  According to the above configuration, since the first center of gravity adjustment unit is provided, the center of gravity of the gate can be set to a desired position so that the gate can rotate in an appropriate rotation direction at an appropriate rotation speed. In addition, according to the configuration described above, since the second center-of-gravity adjustment unit is provided, the center-of-gravity position of the arm unit can be set to a desired position so that the arm unit can rotate in an appropriate rotation direction at an appropriate rotation speed.

  In the hopper opening / closing mechanism according to the present invention, in the configuration described above, the hopper is a weighing hopper for holding the article in order to measure the weight of the article, and the discharge port is closed by the gate. In this case, the drive unit and the arm unit may not be in contact with each other.

  Here, the state where the hopper is the weighing hopper and the discharge port is closed by the gate is the timing when the weight of the article stored in the weighing hopper is weighed.

  According to the said structure, when it exists in the state by which the discharge port was closed by the gate, it is comprised so that a drive part and an arm part may not contact. For this reason, the vibration accompanying the operation of the drive unit can be prevented from being transmitted to the weighing hopper via the arm, and appropriate weighing can be performed.

  The present invention has the above-described configuration, and the hopper opening and closing mechanism according to the present invention has an effect that the hopper gate can be closed with a simple configuration without using a spring.

It is a schematic diagram which shows an example of the principal part structure of the combination scale which concerns on embodiment of this invention. It is a figure which shows an example of a structure of the actuator unit with which the combination weigher of FIG. 1 is provided. It is a side view which shows an example of a structure of the measurement hopper in the combination weigher shown in FIG. It is a top view which shows an example of a structure of the measurement hopper in the combination weigher shown in FIG. It is a side view which shows an example of a structure of the closed state of the combination weigher shown in FIG. It is a side view which shows an example of the structure of the open state of the combination weigher shown in FIG. It is a schematic diagram for demonstrating an example of the gravity center position of each structural member in the opening / closing mechanism which the combination weigher shown in FIG. 1 has. It is a figure which shows the structure of the opening / closing mechanism of the gate of the weighing hopper which concerns on a prior art. It is a figure which shows the structure of the opening / closing mechanism of the gate of the weighing hopper which concerns on a prior art.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference symbols throughout all the drawings, and redundant description thereof is omitted.

(Main components of combination weigher)
First, with reference to FIG. 1, the principal part structure of the combination scale 1 which concerns on embodiment of this invention is demonstrated. FIG. 1 is a schematic diagram illustrating an example of a main part configuration of a combination weigher 1 according to an embodiment of the present invention.

  As shown in FIG. 1, the combination balance 1 is provided with a center base body 17, which is supported by, for example, four legs (not shown) and corresponds to the main body of the combination balance 1. .

  Here, the center base body 17 has a substantially inverted polygonal frustum-shaped appearance formed by the lower wall 17A, the upper wall 17B, and the side wall 17C, but is not limited thereto. The center substrate 17 may have another shape, for example, a cylinder or a regular polygonal column. The dispersion feeder 11 and the straight traveling trough 12 are disposed on the upper wall 17B of the center base body 17, and the supply hopper 13, the weighing hopper 14, and the like are disposed outside the side wall 17C.

  Next, each part which the combination scale 1 which concerns on this Embodiment which has the external shape mentioned above has is demonstrated.

  The dispersion feeder 11 is disposed in the center of the upper wall 17B of the center base body 17, and disperses the objects to be weighed (articles) supplied from an external supply device (not shown) radially by vibrations, and linearly feeds the feeder 20. To supply. The dispersion feeder 11 has a conical shape so that the objects to be weighed can be dispersed radially. In addition, the dispersion feeder 11 determines the vibration width and the operation time so as to uniformly disperse the objects to be weighed according to the control instruction from the control device 18.

  The rectilinear trough 12 is disposed below and around the dispersion feeder 11, and the object to be weighed sent from the dispersion feeder 11 is sent to each supply hopper 13 by vibration given from the rectilinear feeder 20. It is a waste. The linear feeder 20 has its vibration width and operation time controlled by the control device 18. Below the straight trough 12, a supply hopper 13 and a weighing hopper 14 are respectively provided on the center base 17, and a set of the supply hopper 13 and the weighing hopper 14 is formed on the outer periphery (side wall 17C) of the center base 17. Along each other, they are arranged in a circle at a predetermined interval.

  The supply hopper 13 receives an object to be weighed sent from the straight traveling trough 12 arranged at a position higher than itself, and includes a discharge gate 13A and a supply hopper main body 13B. The supply hopper 13 temporarily holds the object to be weighed sent from the straight trough 12, and discharges the object to be weighed to the weighing hopper 14 arranged below the object. For this reason, supply hopper main-body part 13B is carrying out the cylindrical shape with which the upper surface and the bottom face opened. That is, the supply hopper main body 13 </ b> B has an open top surface for receiving an object to be weighed sent from the straight traveling trough 12 and an open bottom surface for sending the received object to be weighed to the weighing hopper 14. When holding the object to be weighed in the supply hopper 13, the opening in the bottom surface of the supply hopper main body 13B is closed by the discharge gate 13A. When discharging the object to be weighed to the weighing hopper 14, the discharge gate 13A is opened at a predetermined timing.

  The weighing hopper 14 temporarily holds the object to be weighed while reading the weight of the object to be weighed supplied from the supply hopper 13 by the load cell 32 which is a load detector. The weighing hopper 14 includes a discharge gate 14A and a weighing hopper main body 14B. The weighing hopper main body 14B has a shape in which an upper surface and a bottom surface are opened, similarly to the supply hopper main body 13B. During the weighing of the object to be weighed, the opening on the bottom surface is closed by the discharge gate 14A, and when the object to be weighed is discharged to the collecting chute 16, the discharge gate 14A is opened at a predetermined timing. .

  Below the weighing hoppers 14 arranged in a circle on the outer periphery of the center base body 17, a substantially inverted frustoconical collective chute 16 is disposed, and the object to be weighed discharged from the weighing hopper 14 selected as the discharge combination. The object slides down on the collecting chute 16 and is discharged from a lower discharge port 16a to, for example, a packaging machine (not shown).

  The control device 18 includes a CPU and a microcontroller having a ROM and RAM memory in which the CPU operation program, operation parameters, and the like are stored, and controls the overall operation of the combination weigher 1. is there. The control device 18 can control the overall operation of the combination weigher 1 when the CPU executes the operation program stored in the ROM. More specifically, the control device 18 instructs the dispersion feeder 11 and the rectilinear feeder 20 to control vibration, amplitude, and operation time thereof. Further, the control device 18 controls the stepping motors 30 and 31 so as to open and close the discharge gate 13A of the supply hopper 13 and the discharge gate 14A of the weighing hopper 14.

  Further, the control device 18 receives a load signal output from the load cell 32 to which the weighing hopper 14 is attached, and calculates the weight of the object to be weighed held by the weighing hopper 14 based on the load signal. It also functions as a means. Furthermore, the control device 18 also functions as a combination unit that performs combination calculation. In this combination calculation, the total weight of the objects to be weighed is within a predetermined weight range (allowable range with respect to the target weight) based on the weight of the object to be weighed calculated by the load cell 32 to which the weighing hopper 14 is attached. Find one combination that yields the value of. If there are a plurality of combinations within the predetermined weight range, one combination having the smallest absolute value of the difference between the total weight of the objects to be weighed and the target weight is obtained. The combination of the weighing hoppers 14 holding the objects to be weighed corresponding to the combinations obtained in this way is set as the discharge combination.

  Then, the control device 18 instructs the stepping motor 31 that performs the opening / closing operation to open / close the discharge gate 14A of the weighing hopper 14 selected as the discharge combination at a predetermined timing. Based on the control instruction from the control device 18, the stepping motor 31 rotates the drive lever 39 at a predetermined speed. As a result, the drive lever 39 engages the drive roller 41 provided at the tip of the drive lever 39 with the toggle arm 25 and rotates the toggle arm 25 around the rotation axis of the toggle arm coupling portion 27. In accordance with the rotational movement of the toggle arm 25, the end portion of the link 26 joined to the discharge gate 14A moves to open or close the discharge gate 14A. By opening and closing the discharge gate 14A in this way, it is possible to discharge the object to be weighed from the weighing hopper body 14B or to hold the object to be weighed in the weighing hopper body 14B.

  Further, the weighing hopper 14 that has been emptied by discharging the object to be weighed opens the discharge gate 13 </ b> A of the supply hopper 13 thereabove and supplies the object to be weighed from the supply hopper 13. In addition, the object to be weighed is supplied to the empty supply hopper 13 from the straight traveling trough 12 thereabove. That is, the opening and closing of the discharge gate 14A of the weighing hopper 14, the opening and closing of the discharge gate 13A of the supply hopper 13, and the vibration of the straight traveling trough 12 and the dispersion feeder 11 are interlocked. Is being executed according to.

  The control device 18 is not necessarily configured by a single control device, and a plurality of control devices are distributed and configured to control the operation of the combination weigher 1 in cooperation with each other. Also good.

  Further, in the combination weigher 1 according to the present embodiment, opening / closing control of the weighing unit 4 including the load cell 32 for weighing the object to be weighed temporarily held in the weighing hopper main body 14B, and the discharge gate 13A and the discharge gate 13B. Stepping motors 30 and 31 for performing the operation, driving levers 38 and 39 rotated by the stepping motors 30 and 31, and an opening / closing control unit (driving unit) including driving rollers 40 and 41 provided at the distal ends of the driving levers 38 and 39. 3) are integrally formed as the actuator unit 19. The actuator unit 19 can be detachably attached to the center base body 17.

(Configuration of actuator unit)
Next, the configuration of the actuator unit 19 will be described in detail. First, the configuration of the actuator unit 19 will be described with reference to FIG. FIG. 2 is a diagram showing an example of the configuration of the actuator unit 19 provided in the combination weigher 1 of FIG.

  The actuator unit 19 is detachable from the center base body 17. Further, the actuator unit 19 can be fixed to the center substrate 17 by the mounting bolt 51. Although the actuator unit 19 is covered by the front plate portion 15, for convenience of explanation, the portion where the measuring unit 4 (load cell 32 or the like) is disposed is illustrated with the front plate portion 15 removed. Yes.

  As described above, the combination weigher 1 includes the stepping motors 30 and 31 for performing the opening / closing control of the discharge gates 13A and 14A of the supply hopper 13 and the weighing hopper 14 as the opening / closing control unit 3, and the load cell 32 as the weighing unit 4, respectively. I have.

  Drive levers 38 and 39 are attached to the stepping motors 30 and 31, respectively, which rotate in accordance with the rotational movement of the rotation shafts of the stepping motors 30 and 31. Drive rollers 40 and 41 for engaging with the opening / closing mechanisms of the supply hopper 13 and the weighing hopper 14 are provided at the distal ends of the drive levers 38 and 39, respectively. Here, the opening / closing mechanism (hopper opening / closing mechanism) of the supply hopper 13 and the weighing hopper 14 is a link mechanism in which a discharge gate is connected to an L-shaped toggle arm via a link, the details of which will be described later.

  In this specification, as shown in FIG. 2, the driving rollers 40 and 41 are driven when they are in a direction directly above the circumference on which the driving rollers 40 and 41 move (that is, at 12 o'clock). The origin position of the levers 38 and 39 is set. The drive levers 38 and 39 are configured such that the drive rollers 40 and 41 are in contact with the opening / closing mechanism at a position rotated counterclockwise by 30 ° from the origin position.

  As shown in FIG. 2, the actuator unit 19 has a pair of hangers 23 and 24 for attaching the supply hopper 13 and the weighing hopper 14 to the side surface where the supply hopper 13 and the weighing hopper 14 are arranged. Is provided.

  As shown in FIG. 2, the pair of hangers 23, 24 has an elongated flat plate shape, and is inclined and extended upward from the lower end of the actuator unit 19 toward the side on which the weighing hopper 14 is attached.

  In FIG. 2, for convenience of explanation, the hangers 23 and 24 arranged on the depth side of the paper surface of the pair of hangers 23 and the pair of hangers 24 are omitted. Furthermore, the supply hopper 13 and the weighing hopper 14 are illustrated as being removed.

  The hanger 23 is fixed by a hanger fixing bolt 52 at the front plate portion 15.

  On the other hand, the hanger 24 is fixed together with the load side bracket 58 by hanger fixing bolts 53a and 53b. The load side bracket 58 is fixed to the side portion of the load cell 32 by bracket fixing bolts 54a and 54b. Accordingly, the hanger 24 and one side portion of the load cell 32 are joined via the load side bracket 58.

  A bracket 59 is attached to the other side portion of the load cell 32 by bracket fixing bolts 56a and 56b. Further, the bracket 59 is fixed to the front plate portion 15 by a bracket fixing bracket 60. Further, the load cell 32 is fixed on the bracket 59 side, and a weight load from the weighing hopper 24 is received via the hanger 24 on the side of the load cell 32 where the load side bracket 58 is attached.

  More specifically, the load cell 32 is configured to measure the weight load of the object to be weighed supplied to the weighing hopper 14 as follows. That is, the load cell 32 has a plurality of strain gauges (not shown). One side surface (the side on which the bracket 59 is attached) of the load cell 32 is fixed in the actuator unit 19. Further, the weight of the object to be weighed in the weighing hopper 14 is applied as a load via the hanger 24 to the load cell 32 on the side opposite to the fixed side (the side on which the load side bracket 58 is attached). Due to this load, the strain body of the load cell 32 is distorted, and this strain is detected by a strain gauge. In this way, the weight of the object to be weighed temporarily held in the weighing hopper 14 can be detected. The strain detected by the strain gauge is configured to be output as an electrical signal to the control device 18 from an output connector (not shown) fixed on the load cell by the connector fixing bracket 55.

  In addition, a plate 61 for sealing the inside of the actuator unit 19 is provided at the bottom of the actuator unit 19, and the plate 61 is fixed to the actuator unit 19 by plate fixing brackets 57a and 57b.

  As shown in FIG. 2, the opening / closing control unit 3 and the measuring unit 4 are arranged so as to be physically separated.

(Configuration of hopper)
Next, the structure of the hopper attached to the actuator unit 19 will be described with reference to FIGS. FIG. 3 is a side view showing an example of the configuration of the weighing hopper 14 in the combination weigher 1 shown in FIG. FIG. 4 is a plan view showing an example of the configuration of the weighing hopper 14 in the combination weigher 1 shown in FIG.

  The supply hopper 13 and the weighing hopper 14 have the same configuration except that the latter requires edge cutting with the opening / closing control unit 3. For this reason, in this specification, the weighing hopper 14 is taken as an example, and the configuration of the hopper will be described.

  As shown in FIGS. 3 and 4, the weighing hopper 14 includes a discharge gate 14 </ b> A, a weighing hopper main body 14 </ b> B, and a pair of connecting frames 14 </ b> C. The discharge gate 14A opens and closes an opening (discharge port) formed below the weighing hopper body 14B. In the weighing hopper 14, the discharge gate 14A is rotatably joined to the side surface of the weighing hopper main body 14B by the gate coupling portion 28.

  When the weighing hopper 14 is viewed from above (in the plan view of the weighing hopper 14), the surface on which the weighing hopper 14 is attached to the center base body 17 is the back surface, and the surface formed at a position facing the back surface is the front surface. To do. A pair of surfaces arranged adjacent to the back surface and the front surface so as to form a substantially rectangular parallelepiped cylinder together with the back surface and the front surface are referred to as side surfaces.

  Here, each of the pair of connection frames 14C is a thin plate whose main surface is a surface in parallel with each of the pair of side surfaces of the weighing hopper main body portion 14B, and is fixed to the side surface of the weighing hopper main body portion 14B. Projecting toward the center base body 17 so as to extend downward from above. A portion of the connecting frame 14C protruding from the weighing hopper main body 14B is provided with a pair of bars 29a and 29b extending in the horizontal direction so as to cross between the pair of connecting frames 14C. The weighing hopper 14 can be attached to the actuator unit 19 by hooking these bars 29a and 29b on the hanger 24 for the weighing hopper.

As shown in FIGS. 3 and 4, a thin-plate-like toggle arm 25 is rotatably attached to the main surface of the protruding portion of the connection frame 14 </ b> C by a toggle arm coupling portion 27.
A discharge gate 14A is rotatably attached to the weighing hopper main body 14B by a gate coupling portion 28 at a joint portion of the connecting frame 14C with the weighing hopper main body 14B.

  The toggle arm 25 and the discharge gate 14A are connected by a link 26. That is, one end of the rod-shaped link 26 whose both ends are circular is rotatably connected to the discharge gate 14A by the first link fulcrum 33, and the other end is rotatably connected to the toggle arm 25 by the second link fulcrum 34. Has been.

  Thus, the discharge gate 14A, the toggle arm 25, and the link 26 form an opening / closing mechanism for the discharge gate 14A. Here, the opening / closing mechanism will be described in more detail.

(Hopper opening and closing mechanism)
First, the discharge gate 14A is formed by bending both sides of a flat plate substantially at a right angle. As shown in FIG. 3, each side surface has a substantially tapered shape from one end serving as a joint portion with the weighing hopper main body 14 </ b> B toward the other end located at the bottom of the weighing hopper 14. ing. A part of the end surface that becomes a joint portion with the weighing hopper main body portion 14 </ b> B is circular, and this circular portion becomes a contact surface with the gate coupling portion 28. In addition, an opening for penetrating the bolt of the gate coupling portion 28 is formed in the circular portion. The gate coupling portion 28 attaches the discharge gate 14A to the weighing hopper main body portion 14B so that the discharge gate 14A rotates about a bolt as a rotation axis (rotation center A).

  Further, one end of the link 26 is attached to one side surface of the discharge gate 14 </ b> A by a first link fulcrum 33. In the first link fulcrum 33, the link 26 is rotatable with respect to the discharge gate 14A with the bolt of the first link fulcrum 33 as a rotation axis.

  A gate center-of-gravity adjusting portion 22 is provided in the main surface of the discharge gate 14A, that is, a surface along the back surface of the weighing hopper main body portion 14B and in the vicinity of the upper end portion when the weighing hopper 14 is closed. . The gate center-of-gravity adjustment unit 22 adjusts the position of the center of gravity of the discharge gate 14A when attached to the main body 14B. In the present embodiment, a thin plate-shaped metal weight is provided on the main surface of the discharge gate 14 </ b> A as the gate center-of-gravity adjustment unit 22.

  Each of the pair of connecting frames 14C is fixedly provided on both side surfaces of the weighing hopper main body 14B as shown in FIG. 4, and a part thereof protrudes from the weighing hopper main body 14B. The pair of connection frames 14 </ b> C are formed by bending a plate material, for example, and extend so as to be parallel to each other from the weighing hopper body 14 </ b> B toward the center base body 17. The protruding portions of the connecting frames 14C have a substantially L shape that protrudes in a substantially horizontal direction from the upper position of the side surface of the weighing hopper main body 14B and is bent so as to extend toward the lower portion (bottom portion).

  Bars 29a and 29b are provided in the middle of the projecting portions of the pair of connection frames 14C and at the front end portions thereof so as to horizontally cross between the pair of connection frames 14C.

  Further, a toggle arm coupling portion 27 is provided at a position that bends downward in the connection frame 14C. The toggle arm 25 is rotatably attached to the connecting frame 14C using the bolt of the toggle arm coupling portion 27 as a rotation axis. Further, a locking portion 35 having a substantially rectangular shape that protrudes toward the front side of the sheet of FIG. 3 is provided in the middle portion of the protruding portion of the connecting frame 14C on the side of the center base body 17 side. The locking portion 35 is in contact with the side portion of the toggle arm 25 and restricts the range of the rotational movement around the left of the toggle arm 25.

  When the toggle arm 25 rotates clockwise, the main surface of the discharge gate 14A moves toward the protruding portion of the connecting frame 14C as the toggle arm 25 rotates clockwise. For this reason, the range in which the toggle arm 25 can rotate clockwise is up to a position where the main surface of the discharge gate 14A and the connection frame 14C are in contact with each other at the maximum.

  The toggle arm 25 rotates about the rotation axis of the toggle arm coupling portion 27 by the force exerted from the drive lever 39, so that the toggle gate 25 and the discharge gate 14A are connected to each other via the link 26. Opening and closing can be controlled. The toggle arm 25 is a substantially L-shaped plate-like member, and a notch 36 is formed at an end thereof. The notch 36 is formed with a guide 37 that protrudes to the back side of the sheet of FIG. 3 so that the drive roller 41 at the end of the drive lever 39 rotated by the stepping motor 31 can be received. It has become.

  In the toggle arm 25, one end of the link 26 is rotatably joined by a second link fulcrum 34 to the end opposite to the end where the notch 36 is formed. Further, a toggle arm center-of-gravity adjusting portion 21 is provided at a bent portion of the toggle arm 25. The toggle arm center-of-gravity adjustment unit 21 adjusts the center of gravity so that the center of gravity of the toggle arm 25 is on the discharge gate 14A side. For example, a metal weight is attached to the surface of the toggle arm 25 near the bent portion. Can be realized.

  In the present embodiment, the toggle arm center-of-gravity adjusting portion 21 is arranged on the back surface of the toggle arm 25, that is, on the toggle arm 25 so as to be arranged in a gap formed between the toggle arm 25 and the connecting frame 14C. It is provided on the surface on the connection frame 14C side. However, the surface on the side where the toggle arm center-of-gravity adjustment unit 21 is provided is not limited to the back surface, and may be the front surface.

(Weighing hopper open / close operation)
The opening / closing mechanism of the weighing hopper 14 having the above configuration can open and close the weighing hopper 14 as follows. Hereinafter, the opening / closing operation of the weighing hopper 14 will be described with reference to FIGS. 5 and 6. FIG. 5 is a side view showing an example of the configuration of the combination weigher 1 shown in FIG. 1 in the closed state. FIG. 6 is a side view showing an example of the configuration of the combination weigher 1 shown in FIG. 1 in the open state.

  First, in order to move the discharge gate 14A from the state where the weighing hopper 14 shown in FIG. 5 is in the closed state to the open state shown in FIG. 6, each part of the opening / closing mechanism operates as follows.

  That is, in the state shown in the side view of FIG. 6, the drive lever 39 rotates counterclockwise, and the drive roller 41 at the origin position contacts the guide portion 37 of the notch portion 36 and engages with the toggle arm 25. . When the driving roller 41 further rotates counterclockwise, the toggle arm 25 engaged with the driving lever 39 via the driving roller 41 rotates clockwise about the rotation axis of the toggle arm coupling portion 27. Rotate. In this way, the toggle arm 25 rotates clockwise around the rotation axis of the toggle arm coupling portion 27, and the end portion on the side where the notch portion 36 is not formed, that is, the end on the side where the link 26 is joined. The part is lifted upward. As a result, the end of the link 26 on the side connected to the toggle arm 25 is pulled upward, the discharge gate 14A is attracted to the toggle arm 25 via the link 26, and the weighing hopper 14 is opened.

  When the weighing hopper 14 is in the open state, the drive lever 39 rotates 128.5 ° from the state in which the drive roller 41 is in the contact position shown in FIG. At this time, the toggle arm 25 is rotated by 53.5 °, and the discharge gate 14A is rotated by 44 °. For this reason, the ratio of each rotation angle is 2.9: 1.2: 1. On the other hand, in the case of a hopper with a spring that has been conventionally used, the ratio of the respective rotation angles is 2.2: 1.1: 1.

  Here, the ratio of the rotation angle of the stepping motor 31 indicating how much the stepping motor 31 rotates and how much the gate 14A rotates is a measure of the load applied to the stepping motor 31. In the weighing hopper 14 according to the present embodiment, the rotation angle of the stepping motor 31 for rotating the discharge gate 14A by 1 ° is 2.9 ° from the ratio of the rotation angles described above. On the other hand, in the case of a hopper with a spring, the rotation angle of the stepping motor for rotating the discharge gate by 1 ° is 2.2 °.

  In other words, the rotation angle of the stepping motor required for moving the discharge gate by the same angle in the latter is smaller than that in the former. In this way, if the discharge gate is moved at a small rotation angle, the stepping motor requires energy correspondingly. Therefore, the energy required for the stepping motor per unit time is smaller in the stepping motor 31 according to the present embodiment than in the stepping motor of the spring-loaded hopper. That is, the configuration of the weighing hopper 14 according to the present embodiment reduces the load on the stepping motor, and can prevent the stepping motor from stepping out.

  Next, when the drive roller 39 rotates clockwise while the drive roller 41 is in contact with the guide portion 37 of the notch 36, the toggle arm 25 rotates counterclockwise around the rotation axis of the toggle arm coupling portion 27. And the end on the side where the link 26 is joined moves downward. As a result, the discharge gate 14A moves to the weighing hopper main body 14B side via the link 26, and the weighing hopper 14 is closed. When the drive lever 39 continues to rotate clockwise, the drive roller 41 comes out of the notch 36, and when the drive lever 39 reaches the origin position, the rotational movement of the drive lever 39 is stopped.

  It should be noted that at the moment when the drive roller 41 comes out of the notch 36 or is accommodated in the notch 36, the tangential direction of the locus (circumference) of the movement of the drive roller 41 and the inclination of the slit of the notch 36 are as follows. It has become the same direction. Here, the tangent refers to a line connecting the rotation axis of the stepping motor 31 and the center point of the drive roller 41 when the drive roller 41 comes out of the notch 36 or when the drive roller 41 is accommodated. It is a line that makes a right angle.

  That is, at the moment when the drive roller 41 comes out of the notch 36 or is accommodated, the movement of the drive roller 41 moves in the tangential direction. For this reason, the direction of movement of the drive roller 41 and the inclination of the slit of the cutout portion 36 coincide with each other, and vibration generated by the contact between the drive roller 41 and the cutout portion 36 can be suppressed as much as possible.

  Further, in the closed state of the weighing hopper 14, the drive roller 41 comes out of the notch 36, and the drive lever 39 and the toggle arm 25 are separated from each other. Further, as described above, in the actuator unit 19, the opening / closing control unit 3 and the measuring unit 4 are physically separated from each other. Therefore, when the weighing hopper 14 is closed, that is, when the weight of the object to be weighed accommodated in the weighing hopper 14 is measured, the opening / closing control unit 3 and the weighing unit 4 are separated, in other words, the edges are cut. State. Accordingly, it is possible to prevent the influence of vibrations and the like exerted from the stepping motor 31 of the opening / closing control unit 3 in the weighing of the object to be weighed accommodated in the weighing hopper 14.

  In this embodiment, the toggle arm 25 is rotated counterclockwise by the action of the force exerted by the clockwise rotation of the drive lever 39, and is formed below the weighing hopper main body 14B by the discharge gate 14A. The opening was closed. However, in the opening / closing mechanism according to the present embodiment, even if no force is applied to the toggle arm 25 from the drive lever 39, the toggle arm 25 is caused to rotate counterclockwise due to the weight of the discharge gate 14A and the toggle arm 25. The weighing hopper 14 can be closed by rotating the discharge gate 14A. However, the closing operation of the discharge gate 14A is performed in the configuration in which the weighing hopper 14 is closed by the discharge gate 14A using not only the weight of each member constituting the opening / closing mechanism but also the force exerted from the drive lever 39. It is preferable because the speed and timing can be easily controlled. In particular, in the weighing hopper 14, the moving speed of the discharge gate 14 </ b> A is reduced before the opening of the weighing hopper main body 14 </ b> B is closed by the discharge gate 14 </ b> A, so that the discharge gate 14 </ b> A contacts the main body 14 </ b> B. The generated impact sound can be reduced.

  In the combination weigher 1 using the weighing hopper according to the present embodiment, the pulse signal applied to the stepping motor 31 from the contact position between the driving roller 41 and the notch 36 until the discharge gate 14A is fully opened is 142 pulses (0.9 deg / pulse conversion). On the other hand, in the configuration of the combination weigher 1 using the above-described conventional spring-equipped hopper, 115 pulses are provided. For this reason, the combination scale 1 using the weighing hopper according to the present embodiment improves the degree of freedom of the pulse pattern.

  When the weighing hopper 14 is closed, the opening / closing mechanism of the present embodiment forms a so-called toggle mechanism so that the opening of the weighing hopper main body 14B can be held by the discharge gate 14A. It has become. Further, as described above, the discharge gate 14 </ b> A is configured to be in the closed position by the weight of each member constituting the opening / closing mechanism. For this reason, the discharge gate 14A can be maintained in the closed state not only by the above-described toggle mechanism but also by the weight of the opening / closing mechanism.

  By the way, when the weighing hopper 14 is closed, an object to be weighed may be caught between the discharge gate 14A and the weighing hopper main body 14B. In such a case, the positional relationship among the toggle arm 25, the link 26, and the discharge gate 14A is not a positional relationship that allows the discharge gate 14A to be held with sufficient force by the toggle mechanism. Get smaller. Even in such a case, in the opening / closing mechanism of the present embodiment, the discharge gate 14A can be maintained in the closed state by its own weight, particularly the weight of the discharge gate 14A. That is, the magnitude of the torque around the rotation axis (torque generated around the rotation axis of the discharge gate 14A and the toggle arm 25) caused by the weight of the opening / closing mechanism is larger than the weight of the object to be weighed. For this reason, all the force to close the discharge gate 14A is applied to the object to be weighed, and the object to be weighed is pressed against the weighing hopper main body 14B. For this reason, the closed state of the discharge gate 14 </ b> A can be maintained with the object to be weighed in.

(Configuration to realize weighing hopper closing operation only by its own weight)
Here, the principle that the closing operation of the weighing hopper 14 can be realized only by the own weight of each member constituting the opening / closing mechanism will be described with reference to FIG. FIG. 7 is a schematic diagram for explaining an example of the position of the center of gravity of each component in the opening / closing mechanism of the combination weigher 1 shown in FIG.

  First, consider the closing operation of the discharge gate 14A. After the drive roller 41 of the drive lever 39 has moved away from the notch portion 36 of the toggle arm 25, the closing operation of the discharge gate 14A is governed by the inertia and weight in each part of the opening / closing mechanism. For this reason, in order for inertia to act in the direction in which the discharge gate 14A closes and force to act in the direction in which the discharge gate 14A closes, the relationship between the gravity center position of the discharge gate 14A and the gate coupling portion 28, and toggle The relationship between the position of the center of gravity of the arm 25 and the toggle arm coupling portion 27 is an important factor.

  That is, by setting the position of the center of gravity of the discharge gate 14A to be shifted from the rotation center A of the gate coupling portion 28, the balance is lost and the discharge gate 14A can be rotated by its own weight. Further, by setting the position of the center of gravity of the toggle arm 25 to be shifted from the rotation center B of the toggle arm coupling portion 27, the balance arm is out of balance and the toggle arm 25 can be rotated by its own weight.

  Therefore, in the opening / closing mechanism according to the present embodiment, as shown in FIG. 7, the positions of the centers of gravity of the discharge gate 14 </ b> A, the toggle arm 25, and the link 26 are in the following relationship when the weighing hopper 14 is closed. Designed.

  That is, the position of the center of gravity g1 of the discharge gate 14A is a straight line extending in the vertical direction through the rotation center A of the gate coupling portion 28 when the weighing hopper 14 is viewed from the side when the weighing hopper 14 is closed as shown in FIG. The center substrate 17 side (on the right side of FIG. 3) from the top or the straight line. In the opening / closing mechanism according to the present embodiment, the gate center-of-gravity adjusting portion 22 is provided on the main surface of the discharge gate 14A so that the discharge gate 14A has such a center of gravity position.

  Further, as described above, the side surface of the discharge gate 14A has a shape that tapers from the end portion on the side where the gate coupling portion 28 is provided toward the bottom portion of the weighing hopper 14. Also by this, the position of the center of gravity g1 of the discharge gate 14A is adjusted so as to be closer to the center base body 17 side (right side in FIG. 7) than the straight line passing through the rotation center A of the gate coupling portion 28 and extending in the vertical direction. Yes.

  By setting the position of the center of gravity g1 of the discharge gate 14A to the above-described position, the discharge gate 14A is discharged from the position of the discharge gate 14A when the weighing hopper 14 is open to the position of the discharge gate 14A when the weighing hopper 14 is closed. Due to the dead weight of the gate 14A, a force that rotates the discharge gate 14A clockwise around the rotation center A works.

  On the other hand, the position of the center of gravity g2 of the toggle arm 25 is determined by the discharge gate from a straight line passing through the rotation center B of the toggle arm coupling portion 27 and extending in the vertical direction when the weighing hopper 14 is viewed from the side when the weighing hopper 14 is closed. 14A is disposed (the left side in FIG. 7). In particular, when the weighing hopper 14 is closed, the weighing hopper 14 is viewed from the side, passes through the rotation center B of the toggle arm coupling portion 27, and extends from the straight line on the side where the discharge gate 14A is disposed (see FIG. 7). It is preferable that the center of gravity g2 is on a straight line extending in the horizontal direction passing through the rotation center B. A toggle arm center-of-gravity adjustment unit 21 is provided on the back surface of the toggle arm 25 so that the toggle arm 25 has such a center-of-gravity position.

  By setting the center of gravity g2 of the toggle arm 25 to the position described above, the toggle arm 25 is toggled from the position of the discharge gate 14A when the weighing hopper 14 is open to the position of the discharge gate 14A when the weighing hopper 14 is closed. Due to the weight of the arm 25, a force that rotates the toggle arm 25 counterclockwise around the rotation center B acts.

  Accordingly, by setting the center of gravity g1 of the discharge gate 14A and the center of gravity g2 of the toggle arm 25 to the positions described above, the toggle arm 25 can be turned counterclockwise even if the force from the drive lever 39 is not exerted on the toggle arm 25. It is possible to rotate and operate the weighing hopper 14 in the closing direction by the discharge gate 14A.

  Furthermore, the opening / closing mechanism according to the present embodiment is configured to hold the closed state of the discharge gate 14A by the toggle mechanism. In other words, as described above, by adjusting the respective gravity center positions of the discharge gate 14A and the toggle arm 25, the discharge gate 14A, the toggle arm 25, and the link 26 work in conjunction with each other as follows. Can do.

  That is, due to the structure of the weighing hopper 14 according to the present embodiment, in the closing operation of the discharge gate 14A, the discharge gate 14A comes into contact with the weighing hopper body 14B, and the movement speed of the discharge gate 14A becomes zero. At this time, the second link fulcrum 34 rotates clockwise by inertia with the first link fulcrum 33 as the rotation center. Furthermore, since the toggle arm 25 is also moving in the closing direction of the discharge gate 14A as described above, the rotation torque from the toggle arm 25 is applied to the second link fulcrum 34 from the moment when the toggle mechanism works in the opening / closing mechanism, Both the discharge gate 14A and the rotational torque from the link 26 are applied. When the rotational torque applied from both exceeds the torque required to establish the toggle mechanism, the torque mechanism is activated.

  In order to make the toggle mechanism work, the center of gravity g3 of the link 26 connecting the toggle arm 25 and the discharge gate 14A is preferably set to the following position.

  That is, the position of the center of gravity g3 of the link 26 is based on a straight line connecting the rotation center B of the toggle arm coupling portion 27 and the rotation center C of the first link fulcrum 33 when the weighing hopper 14 is viewed from the side in the closed state. Is the lower point, that is, on the rotation center D side of the second link fulcrum 34 and the midpoint of the link 26.

  That is, the opening / closing mechanism according to the present embodiment regards the link α between the toggle arm coupling portion 27 and the second link fulcrum 34, and the link β between the second link fulcrum 34 and the first link fulcrum 33, It can be considered as a toggle mechanism in which the second link fulcrum 34 is an unfixed joint and the first link fulcrum 33 is regarded as a slider. Here, since the link 26 corresponds to the link β, it is preferable that the center of gravity g3 is at the midpoint of the link 26 so that the first link fulcrum 33 which is a slider moves smoothly.

  Although the configuration of the hopper has been described above by taking the weighing hopper 14 as an example, the supply hopper 13 has the same configuration. However, the supply hopper 13 differs from the weighing hopper 14 in that when the discharge gate is in the closed state, the notch portion of the toggle arm and the drive roller of the drive lever remain engaged and do not leave.

  This is because the drop from the straight trough 12 which is the supply source of the object to be weighed to the supply hopper 13 is larger than the drop from the supply hopper 13 to the weighing hopper 14, and the inside of the supply hopper 13 is more than the inside of the weighing hopper 14. It takes a lot of power. Therefore, in order to prevent the discharge gate of the supply hopper 13 from being opened by this large force, the toggle gate and the drive lever are engaged and the discharge gate is supported by the drive lever.

  Note that in the combination weigher 1 according to the present embodiment, a detection unit (not shown) that detects the operation of each of the stepping motors 30 and 31 is provided. Each of 14 may be comprised so that it can be determined whether it exists in the state which has bitten the to-be-measured object.

  In the above description, the single-open configuration in which the discharge gate 14A is provided only on the back side of the supply hopper 13 and the weighing hopper 14 and the discharge gate 14A opens and closes only on the back side has been described as an example. However, the present invention is not limited to such a single-open configuration, and a discharge gate 14A is also provided on the front side of the supply hopper 13 and the weighing hopper 14, and the pair of discharge gates 14A is opened and closed on both the front side and both sides. It can be used in the same way even in a double door configuration.

  From the foregoing description, many modifications and other embodiments of the present invention are obvious to one skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

  The present invention can be configured to close the discharge gate of the hopper by its own weight without using a spring. Therefore, it can be used for a weighing scale that opens and closes a discharge gate at a desired timing, temporarily holds an article stored in the storage port in the hopper, and discharges the held article from the discharge port.

DESCRIPTION OF SYMBOLS 1 Combination scale 3 Opening / closing control part 4 Weighing part 11 Dispersion feeder 12 Straight advance trough 13 Supply hopper 13A Discharge gate 13B Supply hopper main body part 14 Weighing hopper 14A Discharge gate 14B Weighing hopper main body part 14C Connection frame 16 Collecting chute 17 Center base | substrate 18 Control apparatus DESCRIPTION OF SYMBOLS 19 Actuator unit 21 Toggle arm center-of-gravity adjustment part 22 Gate center-of-gravity adjustment part 23 Hanger 24 Hanger 25 Toggle arm 26 Link 27 Toggle arm coupling part 28 Gate coupling part 29a Bar 29b Bar 30 Stepping motor 31 Stepping motor 32 Load cell 33 First link fulcrum 34 Second link fulcrum 35 Locking portion 36 Notch portion 37 Guide portion 38 Drive lever 39 Drive lever 40 Drive roller 41 Drive roller 50 Fastening member 58 Load side Bracket 59 Bracket A Center of rotation B Center of rotation C Center of rotation D Center of rotation G1 Gate g1 Center of gravity g2 Center of gravity g3 Center of gravity

Claims (4)

The combination operation is performed based on the weight of each of the articles supplied in a distributed manner, and a combination weigher for obtaining a combination in which the total weight of the articles is within an allowable range with respect to the target weight is used to hold the supplied articles. A hopper opening / closing mechanism provided for each article supply destination,
The hopper has a housing portion main body in which a discharge port for discharging a supplied article is formed on the bottom surface, and a gate that is rotatably joined to the housing portion body for opening and closing the discharge port,
A drive unit for applying a force to the gate so as to open the discharge port;
An arm portion that rotates by receiving a force acting from the drive portion;
One end is rotatably joined to the gate, the other end is rotatably joined to the arm portion, and includes a link portion that transmits a force acting from the arm portion to the gate,
A force is applied to the gate so as to close the discharge port by the torque generated around the rotation axis of the arm due to the weight of the arm and the torque generated around the rotation axis of the gate due to the weight of the gate. Hopper opening and closing mechanism.   2. The hopper according to claim 1, wherein the gate and the arm portion are configured such that the center of gravity of each of the gate and the arm portion is shifted from each rotation axis so that the gate rotates in a direction in which the gate closes the discharge port. Opening and closing mechanism. The gate is provided with a first center-of-gravity adjustment unit for adjusting the position of the center of gravity so as to rotate with respect to the housing main body in a direction in which the gate is closed.
The arm portion is provided with a second center-of-gravity adjustment portion for adjusting the position of the center of gravity so that the arm portion rotates so as to apply a force to rotate the housing portion main body in the closing direction of the gate. The hopper opening and closing mechanism according to claim 2. The hopper is a weighing hopper for holding the article in order to measure the weight of the article;
The hopper opening / closing mechanism according to any one of claims 1 to 3, wherein the driving unit and the arm unit are configured not to contact each other when the discharge port is closed by the gate.

Images