JP7593024B2 - Motor drive device - Google Patents

Description

The present invention relates to a motor drive device, for example, a drive device for a DC motor that constitutes the drive source of a transmission mechanism for transmitting a driving force applied from a driving force applying means to a dispensing mechanism that performs a product dispensing operation.

Conventionally, vending machines that sell products such as beverages in containers such as cans or plastic bottles are known to be equipped with product storage racks known as slant racks.

This product storage rack is configured with multiple product storage columns arranged vertically in a product storage passageway that extends at an angle that gradually becomes lower from the upstream side to the downstream side, and stores products in a line in a horizontal position, and each product storage column is provided with a first stopper member, a second stopper member, and a linking member.

The first stopper member is arranged to be swingable so as to move forward and backward in the product storage passage. When the first stopper member moves forward into the product storage passage, it abuts against the most downstream product to prevent the product from being dispensed, while when it moves backward from the product storage passage, it allows the product to be dispensed. The second stopper member is arranged to be swingable so as to move forward and backward in the product storage passage. When the second stopper member moves forward into the product storage passage, it abuts against the second most downstream product to prevent the product from moving downstream, while when it moves backward from the product storage passage, it allows the product to move.

The linking member links the first stopper member and the second stopper member, and is disposed so as to be slidable between the standby position and the dispensing position. When the driving source is stopped, this linking member is located at the standby position, and moves the first stopper member forward and moves the second stopper member backward. When the driving source is driven to move from the standby position to the dispensing position, the linking member moves the first stopper member backward and moves the second stopper member forward.

In such a product storage rack, when a command is given to dispense a product stored in one of the product storage columns, the drive source corresponding to that product storage column is driven to move the linking member from the standby position to the dispensing position, and as a result, the first stopper member moves backward from the product storage passage while the second stopper member moves forward into the product storage passage, dispensing the product furthest downstream in the product storage passage (see, for example, Patent Document 1).

JP 2012-194797 A

In the above-mentioned vending machine, a DC motor is used as a drive source for sliding the linking member, and it is known that the operation of this DC motor is stopped by a change in a physical switch such as a microswitch.

However, using a DC motor as a drive source and a physical switch to determine whether or not the DC motor should be stopped requires the preparation of DC motors and physical switches according to the number of connecting members, and also requires wiring for the physical switches.

It is known that DC motors have the characteristic that they draw a low current when rotating, but draw a large current (stall current) when stopped, such as when the output shaft is locked.

In view of the above-mentioned circumstances, the present invention aims to provide a motor drive device that can eliminate a physical switch and reduce manufacturing costs by stopping the operation of a DC motor based on the magnitude of the current flowing through the DC motor.

In order to achieve the above object, the motor drive device of the present invention is a motor drive device including a control unit that issues a drive command to a DC motor to drive the DC motor, and the control unit is characterized in that, when a current equal to or greater than a predetermined threshold flows through the DC motor after the drive command is issued, the control unit determines that the operation of the DC motor is complete and stops driving the DC motor.

The present invention is also characterized in that in the motor drive device, the control unit monitors whether a current less than the threshold value continues to flow through the DC motor after giving the drive command.

The present invention is also characterized in that in the motor drive device, the DC motor constitutes the drive source of a transmission mechanism for transmitting a driving force applied from a driving force applying means to a dispensing mechanism that performs a product dispensing operation.

According to the present invention, when a current equal to or greater than a predetermined threshold flows through the DC motor after the control unit issues a drive command, the operation of the DC motor is considered to be complete and the drive of the DC motor is stopped. This means that the operation of the DC motor can be stopped based on the magnitude of the current flowing through the DC motor without the need for a physical switch such as a microswitch, and the physical switch can be eliminated, resulting in reduced manufacturing costs.

FIG. 1 is a cross-sectional side view showing a schematic configuration of a vending machine to which a motor drive device according to an embodiment of the present invention is applied. FIG. 2 is a schematic diagram showing the commodity storage device shown in FIG. FIG. 3 is a perspective view showing one of the product storage racks shown in FIGS. 1 and 2. FIG. FIG. 4 is an exploded perspective view showing one of the product storage racks shown in FIGS. 1 and 2. FIG. FIG. 5 is a perspective view of the shelf board shown in FIGS. FIG. 6 is a perspective view of the dispensing mechanism shown in FIGS. FIG. 7 is a perspective view of the dispensing mechanism shown in FIGS. FIG. 8 is a perspective view of one of the dispensing mechanisms shown in FIGS. FIG. 9 is a perspective view of one of the dispensing mechanisms shown in FIGS. FIG. 10 is a cross-sectional side view of one of the dispensing mechanisms shown in FIGS. FIG. 11 is an exploded perspective view of one of the dispensing mechanisms shown in FIGS. 6 and 7. FIG. FIG. 12A is a perspective view of the main body mechanism shown in FIGS. 8 to 11. FIG. FIG. 12B is a perspective view of the main body mechanism shown in FIGS. FIG. 13A is a perspective view of the lever member shown in FIGS. 8 to 11. FIG. FIG. 13B is a perspective view of the lever member shown in FIGS. FIG. 14A is a perspective view of the stopper member shown in FIGS. 8 to 11. FIG. FIG. 14B is a perspective view of the stopper member shown in FIGS. FIG. 15-1 is a perspective view of the pedal member shown in FIGS. 8 to 11. FIG. FIG. 15-2 is a perspective view of the pedal member shown in FIGS. 8 to 11. FIG. FIG. 16A is a perspective view of a slider that constitutes the transmission mechanism shown in FIG. FIG. 16B is a perspective view of a slider that constitutes the transmission mechanism shown in FIG. FIG. 17A is a perspective view showing a dog clutch that constitutes the transmission mechanism shown in FIG. FIG. 17B is a perspective view showing a dog clutch that constitutes the transmission mechanism shown in FIG. FIG. 18 is a perspective view showing the dispensing mechanism in a standby state. FIG. 19 is a schematic diagram showing a circuit configuration of a motor drive device according to an embodiment of the present invention. FIG. 20 is a schematic diagram showing the product storage passage when the dispensing mechanism is in a standby state. FIG. 21 is a perspective view of the dispensing mechanism showing the slider sliding. FIG. 22 is a perspective view of the dispensing mechanism showing the slider sliding. FIG. 23 is a flowchart showing the process contents of the drive monitoring control process performed by the control unit shown in FIG. FIG. 24 is a perspective view of the dispensing mechanism showing a state in which the pedal member is swung upward. FIG. 25 is a perspective view of the dispensing mechanism showing a state in which the pedal member is swung upward. FIG. 26 is a schematic diagram showing the commodity storage passage when the pedal member is swung upward. FIG. 27 is a schematic diagram showing the commodity storage passage when the pedal member is further swung upward. FIG. 28 is an explanatory diagram showing the movement of a commodity dispensed to a dispensing passage.

Below, a preferred embodiment of a motor drive device according to the present invention will be described in detail with reference to the attached drawings.

Figure 1 is a cross-sectional side view showing a schematic configuration of a vending machine to which a motor drive device according to an embodiment of the present invention is applied. The vending machine shown here sells beverages in containers such as plastic bottles or cans, and includes a main cabinet 1 which is the main body of the vending machine.

The main cabinet 1 is constructed by appropriately combining multiple metal plates, and is formed in a rectangular parallelepiped shape with an opening 1a on the front (hereinafter also referred to as the front opening). Inside this main cabinet 1, a storage chamber 2 with a thermally insulated structure is defined in a manner facing the front opening 1a.

An outer door 3 and an inner door 4 are provided at the front of the main cabinet 1. The outer door 3 opens and closes the front opening 1a of the main cabinet 1. The inner door 4 is a door body with a thermal insulation structure, and opens and closes the front of the storage chamber 2.

The storage chamber 2 is provided with a product storage device 10 and a product chute 5. The product storage device 10, which will be described in detail later, stores products and dispenses the corresponding products in response to a dispensing command (sales command). The product chute 5 is provided in the lower area of the product storage device 10 and is inclined so that it gradually becomes lower from the rear to the front. This product chute 5 is for guiding products dispensed from the product storage device 10 through a product discharge opening 4a provided in the inner door 4 to a product removal opening 3a provided in the outer door 3. The product discharge opening 4a is opened and closed by a product discharge door 4b, and the product removal opening 3a is opened and closed by a product removal door 3b. The internal atmosphere of the storage chamber 2 is adjusted to a desired temperature by cooling means and heating means (not shown).

As shown in FIG. 2, the product storage device 10 is configured with multiple product storage racks 11 arranged vertically between a pair of left and right base side panels 10a.

Figures 3 and 4 show one product storage rack 11 shown in Figures 1 and 2, respectively, with Figure 3 being a perspective view and Figure 4 being an exploded perspective view. As shown in Figures 3 and 4, the product storage rack 11 is configured with shelves 12, partitions 13, and a dispensing mechanism 20.

The shelf board 12 is made, for example, of processed sheet metal, and is provided between the base side plates 10a with an incline that gradually lowers from the front to the rear. As shown in FIG. 5, the shelf board 12 has shelf side walls 12a that extend upward at both left and right ends. The shelf board 12 also has a plurality of partition locking holes 12b formed along the left-right direction at a predetermined interval of, for example, about 20 mm, with the front-to-rear direction being the longitudinal direction. Furthermore, the shelf board 12 also has a plurality of mechanism locking holes 12c formed along the left-right direction at the rear end at a predetermined interval of about the same as the partition locking holes 12b.

The partition plate 13 is, for example, made of processed sheet metal, and is a long plate-like member whose longitudinal direction is the front-to-rear direction. This partition plate 13 is formed with multiple locking pieces 13a that protrude downward from the lower end.

By inserting the locking pieces 13a of such a partition plate 13 from above into any of the partition locking holes 12b, the partition plate 13 is locked to the shelf plate 12 in a manner that it extends in the front-to-rear direction on the upper surface of the shelf plate 12. By locking multiple such partition plates 13 between the shelf side walls 12a of the shelf plate 12, multiple product storage columns 14 (four in the illustrated example) can be arranged side-by-side on the upper surface of the shelf plate 12, as shown in FIG. 3.

These product storage columns 14 have product storage passages 14a that extend at an angle that gradually becomes lower from the upstream front to the downstream rear, and are intended to store products in a line in a horizontal position in this product storage passage 14a.

Multiple dispensing mechanisms 20 (four in the illustrated example) are provided along the left-right direction. As shown in Figures 6 and 7, each of these dispensing mechanisms 20 is provided with a rotating drive shaft 30, which is a long rod-shaped member extending along the left-right direction, penetrating it.

The rotary drive shaft 30 has a polygonal prism shape, such as a hexagonal prism, and its left end is connected to the center of the rotation transmission member 31, which has a roughly disk shape. This rotation transmission member 31, which will be described in detail later, is provided so as to be rotatable around its own central axis, and as a result, the rotary drive shaft 30 can also rotate around its own central axis.

Next, the configuration of the dispensing mechanism 20 will be described. Note that although multiple dispensing mechanisms 20 are shown in Figures 6 and 7, these dispensing mechanisms 20 have a common configuration, so the configuration of one dispensing mechanism 20 will be described below, and descriptions of the other dispensing mechanisms 20 will be omitted.

Figures 8 to 11 show the dispensing mechanism 20 shown in Figures 6 and 7, with Figures 8 and 9 being perspective views, Figure 10 being a cross-sectional side view, and Figure 11 being an exploded perspective view. As shown in Figures 8 to 11, the dispensing mechanism 20 comprises a mechanism main body 21. The mechanism main body 21 is a housing made of, for example, a resin material, and houses the lever member 22, the stopper member 23, the pedal member 24, the transmission mechanism 40, and the sold-out detection unit 25.

As shown in Figures 12-1 and 12-2, such a mechanism body 21 has a body engaging portion 211 and a body penetrating portion 212. In the following, the mechanism body 21, lever member 22, stopper member 23, pedal member 24, and transmission mechanism 40 will be described according to the directions shown in Figure 8.

The main body engaging portion 211 is formed at the front end of the mechanism main body 21, and is an elastically deformable resin spring-like portion. This main body engaging portion 211 is formed with a locking projection 211a that protrudes forward, and a pair of left and right locking hook portions 211b that protrude forward below the locking projection 211a. The locking projection 211a can be inserted into the mechanism locking hole 12c of the shelf board 12, and the locking hook portions 211b can be locked to the lower end of the rear end of the shelf board 12 when the locking projection 211a is inserted into one of the mechanism locking holes 12c.

The body through-holes 212 are formed in a pair on the left and right at the rear end portions of both the left and right sides of the mechanism body 21. A circular body through-hole 212a having an inner diameter slightly larger than the maximum width of the rotary drive shaft 30 is formed in the body through-hole 212a, and the rotary drive shaft 30 passes through the body through-hole 212a.

The lever member 22 is made of, for example, a resin material, and as shown in Figures 13-1 and 13-2, has a lever action part 221 and a lever penetration part 222. The lever action part 221 is a substantially flat plate-shaped part.

The lever through-holes 222 are a pair of left and right lever through-holes formed in a manner that protrudes forward from both the left and right ends of the front side of the lever action part 221. The lever through-holes 222 are formed with a circular lever through-hole 222a having an inner diameter slightly larger than the maximum width of the rotary drive shaft 30.

The lever member 22 is housed in the mechanism body 21 with the lever through-hole 222 installed inside the body through-hole 212 in such a manner that the lever action portion 221 protrudes rearward from the mechanism body 21, and the rotation drive shaft 30 passes through the lever through-hole 222a. The lever through-hole 222 is also provided with a lever restriction protrusion 222b that protrudes downward. This lever restriction protrusion 222b is inserted from above into a first restriction long hole 213 (see FIG. 9) formed in the lower rear end of the mechanism body 21. This first restriction long hole 213 is a hole portion whose longitudinal direction is the front-rear direction. This allows the lever member 22 to swing around the central axis of the rotation drive shaft 30 within the range where the lever restriction protrusion 222b abuts against the front and rear edges of the first restriction long hole 213.

The stopper member 23 is made of, for example, a resin material, and as shown in Figures 14-1 and 14-2, has a stopper action portion 231, a stopper arm portion 232, and a stopper through portion 233. The stopper action portion 231 is a portion that extends in the left-right direction, and a stopper action surface 231a is formed at its front end. In addition, a pedestal portion 231b that is slightly recessed from the upper surface of the stopper action portion 231 is formed at the rear end of the stopper action portion 231. The stopper arm portion 232 is a pair of left and right portions that extend rearward from both the left and right ends of the stopper action portion 231.

The stopper through-holes 233 are a pair of left and right stopper through-holes formed in a manner that protrudes rearward from the rear end of the stopper arm portion 232. Each stopper through-hole 233 has a circular stopper through-hole 233a formed therein, the inner diameter of which is slightly larger than the maximum width of the rotary drive shaft 30.

In this type of stopper member 23, each stopper through-hole 233 is installed inside the lever through-hole 222 with the stopper action portion 231 inserted from above into the stopper opening 214 formed in the mechanism body 21, and the rotation drive shaft 30 passes through each stopper through-hole 233a, so that the stopper member 23 is housed in the mechanism body 21. The stopper through-hole 233 is also provided with a stopper restriction protrusion 233b that protrudes downward. This stopper restriction protrusion 233b is inserted from above into a second restriction long hole 215 (see FIG. 9) formed in the lower rear end of the mechanism body 21. This second restriction long hole 215 is a hole portion whose longitudinal direction is the front-rear direction. As a result, the stopper member 23 can swing around the central axis of the rotation drive shaft 30 within a range in which the stopper restriction protrusion 233b abuts against the front and rear edges of the second restriction long hole 215.

A spring member 26 is provided between the stopper member 23 and the lever member 22. This spring member 26 biases the stopper member 23 in the direction in which the stopper restriction protrusion 233b abuts against the front edge of the second restriction long hole 215, i.e., upward. The spring member 26 also biases the lever member 22 in the direction in which the lever restriction protrusion 222b abuts against the rear edge of the first restriction long hole 213, i.e., upward.

The pedal member 24 is made of, for example, a resin material, and as shown in Figs. 15-1 and 15-2, has a pedal base 241, a pedal main body 242, and a pedal action part 243. The pedal base 241 is a cylindrical part whose longitudinal direction is in the left-right direction, and is formed with a circular pedal through-hole 241a having an inner diameter slightly larger than the maximum width of the rotary drive shaft 30. The pedal base 241 has an insertion part 241b formed by cutting out the central area in the left-right direction, and a plurality of transmission recesses 241c are formed in an arc-shaped arrangement on the left side of the insertion part 241b.

The pedal body 242 is a generally flat plate-shaped portion that extends from the pedal base 241 radially outward of the pedal through-hole 241a, i.e., toward the front. A pedal hook portion 242a is formed on the underside of the pedal body 242 so as to protrude downward.

The pedal action portion 243 is a flat plate-shaped portion that extends from the pedal base 241 toward the outside in the radial direction of the pedal through-hole 241a. The pedal action portion 243 is formed so that its left-right width is larger than the left-right width of the pedal base 241 and the left-right width of the pedal body 242.

The pedal member 24 is accommodated in the mechanism body 21 by the rotation drive shaft 30 passing through the pedal through hole 241a of the pedal base 241 between the stopper through portions 233 of the stopper member 23. In other words, the pedal member 24 is accommodated in the mechanism body 21 in a manner that allows it to swing around the central axis of the rotation drive shaft 30.

The transmission mechanism 40 is configured with a clutch motor 41, a slider 42, and a dog clutch 43. The clutch motor 41 is housed in the mechanism body 21 by being held by the motor holding portion 216 (see Figs. 9 and 12-2) of the mechanism body 21, and is a DC motor that rotates forward or backward in response to commands given from the control unit 60 (see Fig. 1) via a harness 44 (see Fig. 11).

The clutch motor 41 is the object to be driven by the motor drive device 70 (see FIG. 20), which is an embodiment of the present invention, and will be described in detail later.

The slider 42 is made of, for example, a resin material, and is provided so as to be slidable in the left-right direction in the mechanism body 21. As shown in Figures 16-1 and 16-2, such a slider 42 has a slider body 421 and a slider holder 422.

The slider body 421 is configured with a notch formed in a roughly rectangular parallelepiped, and has a motor engagement portion 421a and a hook locking portion 421b. The motor engagement portion 421a has a female thread formed therein, and is a portion that engages with the clutch motor 41 by screwing into the male thread 411 connected to the clutch motor 41. As a result, when the clutch motor 41 rotates forward and the male thread 411 rotates in one direction, the slider 42 slides to the left in a manner approaching the clutch motor 41, and when the clutch motor 41 rotates reverse and the male thread 411 rotates in the other direction, the slider 42 slides to the right in a manner moving away from the clutch motor 41.

The hook locking portion 421b is a flat portion configured as the opening edge of the slider recess 423 formed at the upper part to the right of the motor engagement portion 421a. This hook locking portion 421b can lock with the pedal hook portion 242a when the pedal hook portion 242a enters the slider recess 423.

The slider holding portion 422 is provided at the rear end of a flat plate that protrudes rearward from the slider body portion 421. This slider holding portion 422 has a cylindrical shape with a holding hole 422a formed inside.

The dog clutch 43 is made of, for example, a resin material, and as shown in Figures 17-1 and 17-2, has a clutch base 431, a clutch engagement portion 432, and a clutch transmission portion 433. The clutch base 431 is a cylindrical portion, and its outer diameter is larger than the inner diameter of the retaining hole 422a of the slider retaining portion 422.

The clutch engagement portion 432 is a cylindrical portion formed in such a manner that it protrudes to the right from the right end face of the clutch base 431. A hexagonal connecting hole 434 that fits the external shape of the rotary drive shaft 30 is formed inside the clutch base 431 and the clutch engagement portion 432. The outer diameter of the clutch engagement portion 432 is smaller than the outer diameter of the clutch base 431 and slightly smaller than the inner diameter of the retaining hole 422a of the slider retaining portion 422. Furthermore, the extension length of the clutch engagement portion 432 in the left-right direction is greater than the left-right length of the slider retaining portion 422, and a clutch hook portion 432a is formed at the right end portion of the clutch engagement portion 432.

The clutch transmission part 433 is a part that extends in an arc shape on a part of the outer end surface of the clutch base part 431. On the left surface of this clutch transmission part 433, transmission protrusions 433a are formed so as to be arranged in an arc shape and protrude to the left. These transmission protrusions 433a are capable of entering the transmission recess 241c.

The dog clutch 43 is rotatably held on the slider 42 by the clutch engagement portion 432 entering the holding hole 422a of the slider holding portion 422 from the left and the clutch hook portion 432a engaging with the right end portion of the slider holding portion 422. The dog clutch 43 is inserted into the insertion portion 241b of the pedal base 241 of the pedal member 24, and is housed in the mechanism main body 21 with the rotary drive shaft 30 passing through the connecting hole 434.

The sold-out detection unit 25 (see FIG. 8) is housed in the mechanism main body 21 in such a manner that the sold-out contact 251 can protrude upward from the arm opening 232a formed in the stopper arm 232 on the right side of the stopper member 23. This sold-out detection unit 25 detects the presence of a product when the sold-out contact 251 is pressed and positioned below the arm opening 232a, and detects the absence of a product when the sold-out contact 251 is positioned above the arm opening 232a. The detection result by this sold-out detection unit 25 is provided to the control unit 60 as a detection signal.

The dispensing mechanism 20 having such a configuration is attached to the shelf board 12 by inserting the locking protrusion 211a constituting the main body engagement portion 211 of the mechanism main body 21 into any of the mechanism locking holes 12c in the shelf board 12 and locking the locking hook portion 211b to the lower edge portion of the rear end portion of the shelf board 12, and is provided downstream of the product storage passage 14a of the product storage column 14.

When the dispensing mechanism 20 is in a standby state as shown in Figures 8 to 10, the slider 42 is positioned at a position farther away from the clutch motor 41, and the pedal hook portion 242a of the pedal member 24 enters the slider recess 423 and engages with the hook engagement portion 421b. Therefore, the pedal member 24 is in a state in which the pedal action portion 243 protrudes upward from the mechanism body 21 and moves forward into the product storage passage 14a. Note that by positioning the slider 42 at a position farther away from the clutch motor 41, the dog clutch 43 held by the slider holding portion 422 and the pedal member 24 are separated from each other, as shown in Figure 18.

The base portion 231b of the stopper member 23 is pressed against the pedal body portion 242 of the pedal member 24, causing the stopper member 23 to swing downward against the biasing force of the spring member 26, and the stopper action portion 231 enters the stopper opening 214 from above, causing the stopper member 23 to move backward from the product storage passage 14a. As a result, the top surfaces of the stopper action portion 231, stopper arm portion 232 and pedal body portion 242 of the stopper member 23 form the same plane as the top surface of the mechanism body portion 21.

However, the lever member 22 is swung upward by the force of the spring member 26 alone until the lever regulating protrusion 222b abuts the rear edge of the first regulating long hole 213, and moves forward into the dispensing passage 50 extending in the vertical direction and provided at the rear side of the product storage rack 11, as shown in Figures 1 and 2.

The base back plate 10b of the product storage device 10, which forms the back surface of the dispensing passage 50, is provided with a number of guide protrusions 51 that protrude into the dispensing passage 50. The guide protrusions 51 are provided so as to extend in the left-right direction below the height level of the dispensing mechanism 20 of each product storage rack 11, and more specifically, in vertically adjacent product storage racks 11, they are provided at a height level intermediate between the height level of the dispensing mechanism 20 of the upper product storage rack 11 and the height level of the dispensing mechanism 20 of the lower product storage rack 11.

As shown in FIG. 2, the outer end surface of the rotation transmission member 31 connected to the rotary drive shaft 30 is engaged with a part of the transmission cable 32 connected endlessly. The transmission cable 32 is partially engaged with the drive pulley 33, and is displaced along its extension direction when the drive pulley 33 rotates around its central axis driven by the drive motor 34. In other words, as the transmission cable 32 is displaced with the rotation of the drive pulley 33, the rotation transmission member 31 also rotates around its own central axis, and the rotary drive shaft 30 also rotates around its own central axis. The drive motor 34 rotates forward or backward in response to a command given from the control unit 60 electrically connected thereto. The control unit 60 can detect the rotation angle of the rotation transmission member 31 based on the detection result given by a rotation detection unit (not shown), such as an encoder, provided near each rotation transmission member 31.

Figure 19 is a schematic diagram showing the circuit configuration of a motor drive device according to an embodiment of the present invention. The motor drive device 70 shown here is an example of a device for monitoring the drive of the clutch motor 41, and includes a driver circuit 71, a binarization circuit 73, and a control unit 60.

The driver circuit 71 is connected to the clutch motor 41 and to the control unit 60. When a motor drive command is given from the control unit 60, the driver circuit 71 supplies power to the terminals of the clutch motor 41, and when a motor drive stop command is given from the control unit 60, the driver circuit 71 stops the supply of power to the terminals of the clutch motor 41.

The binarization circuit 73 is equipped with a comparator 73a, and when the current flowing through the clutch motor 41 and amplified by the differential amplifier circuit 72 is equal to or greater than a preset threshold, it sends a signal to the control unit 60 indicating that the clutch motor 41 has been locked. The threshold value here is a threshold value large enough to detect that a stall current has flowed through the clutch motor 41. When the current flowing through the clutch motor 41 and amplified by the differential amplifier circuit 72 is less than the threshold, the binarization circuit 73 sends a signal to the control unit 60 indicating that a steady-state current has been input.

The control unit 60 comprehensively controls the operation of each part of the product storage device 10, and also comprehensively controls the operation of the drive unit 70 in accordance with programs and data stored in a memory (not shown). Such a control unit 60 performs the drive monitoring and control process for the drive unit 70, which will be described later.

The control unit 60 may be realized, for example, by having a processing device such as a CPU (Central Processing Unit) execute a program, i.e., by software, or may be realized by hardware such as an IC (Integrated Circuit), or may be realized by a combination of software and hardware.

Next, the product dispensing operation by the product storage device 10 will be described. For ease of explanation, the following will be described using one product storage column 14 as an example.

When the dispensing mechanism 20 is in a standby state, as described above, only the pedal member 24 is advanced into the product storage passage 14a, and as shown in FIG. 20, the pedal action part 243 comes into contact with the downstream most product W1 of the product storage passage 14a. As a result, the products in the product storage column 14 are stored in a line along the product storage passage 14a, and are restricted from leaving the product storage passage 14a.

Then, when the user selects a product, the vending machine control unit (not shown), which controls the overall operation of the vending machine, issues a command to dispense the product stored in the product storage column 14. The control unit 60 drives the clutch motor 41 of the dispensing mechanism 20 installed on the rear side of the product storage column 14 to rotate forward. This causes the male screw 411 to rotate in one direction, and as shown in FIG. 21, the slider 42 slides leftward in a manner approaching the clutch motor 41. As the slider 42 slides leftward in this manner, the dog clutch 43 held by the slider 42 also slides leftward. As a result, as shown in FIG. 22, the transmission protrusions 433a of the dog clutch 43 enter the transmission recesses 241c of the pedal member 24 and are connected to the pedal member 24. As the slider 42 slides leftward, the hook engagement portion 421b and the pedal hook portion 242a are released from their engagement state.

When the clutch motor 41 is driven in the forward direction by the control unit 60, the control unit 60 performs the following drive monitoring control process. Figure 23 is a flowchart showing the process of the drive monitoring control process performed by the control unit 60 shown in Figure 19.

In this drive monitoring control process, the control unit 60 sends a motor drive command (forward rotation drive command) to the driver circuit 71 (step S101), and waits for a predetermined reference time to elapse after sending the motor drive command (step S102). This reference time is stored in memory and is set to prevent detection of the starting current flowing through the clutch motor 41 by sending the motor drive command.

If the reference time has elapsed (step S102: Yes), the control unit waits for the input of a signal indicating that a current equal to or greater than the threshold has been input from the binarization circuit 73 (step S103).

When a signal indicating that a current equal to or greater than the threshold has been input from the binarization circuit 73 (step S103: Yes), the control unit 60 determines that the leftward sliding of the slider 42 has been completed, causing the output shaft of the clutch motor 41 to lock and causing a current equal to or greater than the threshold to flow, i.e., that the operation of the clutch motor 41 has been completed, and sends a motor drive stop command (forward rotation drive stop command) to the driver circuit 71 (step S104), and then returns the procedure to end the current processing.

This makes it possible to stop the operation of the clutch motor 41 based on the magnitude of the current flowing through the clutch motor (DC motor) 41 without requiring a physical switch such as a microswitch.

In the above drive monitoring control process, the control unit 60 monitors whether a steady-state current is continuously flowing through the clutch motor 41 by continuously inputting a signal representing a current less than a threshold value from the binarization circuit 73 during the time period from when a motor drive command (forward rotation drive command) is sent to the driver circuit 71 until a reference time has elapsed.

When the dog clutch 43 and the pedal member 24 are connected, the control unit 60 drives the drive motor 34 in the forward direction. This causes the drive pulley 33 to rotate clockwise when viewed from the right, and the transmission cable 32 is displaced, causing the rotation transmission member 31 to also rotate clockwise when viewed from the right.

When the rotation transmission member 31 rotates in this manner, the rotary drive shaft 30 also rotates around its central axis in a clockwise direction when viewed from the right. When the rotary drive shaft 30 rotates in this manner, the dog clutch 43 that fits the rotary drive shaft 30 also rotates clockwise when viewed from the right. The pedal member 24 connected to the dog clutch 43 then swings backward as shown in FIG. 24.

When the pedal member 24 swings backward, the stopper member 23, whose base portion 231b has been pressed by the pedal body portion 242 of the pedal member 24, is released from the pressure of the pedal member 24, and swings upward until the stopper restricting protrusion 233b abuts against the front edge portion of the second restricting long hole 215, as shown in FIG. 25, and the stopper acting portion 231 protrudes upward from the stopper opening 214 and moves forward into the product storage passage 14a.

When the stopper member 23 advances into the product storage passage 14a in this manner, as shown in FIG. 26, the stopper action surface 231a of the stopper action portion 231 comes into contact with the second product W2 from the downstream side in the product storage passage 14a, restricting the movement of the product W2 toward the downstream side of the product storage passage 14a. In other words, only the product W1 at the most downstream side can be separated from the other products.

The rotation of the rotary drive shaft 30 is maintained by the rotation of the rotary transmission member 31 caused by the drive of the drive motor 34, and the pedal member 24 connected to the dog clutch 43, which rotates due to the rotation of the rotary drive shaft 30, continues to swing backward.

Then, when the rotation detection unit detects that the pedal member 24 has swung backward to a position where the most downstream product W1 can be dispensed into the dispensing passage 50 as shown in FIG. 27, as a rotation angle of the rotation transmission member 31, the control unit 60 temporarily stops driving the drive motor 34.

As a result, the most downstream product W1 is dispensed into the dispensing passage 50 and abuts against the lever member 22. The lever member 22 swings downward in a manner of moving backward from the dispensing passage 50 against the biasing force of the spring member 26, and guides the abutted product to the guide protrusion 51 directly below. As shown in FIG. 28, the product guided to the guide protrusion 51 directly below abuts against the guide protrusion 51 and then abuts against the lever member 22 of one of the dispensing mechanisms 20 constituting the product storage rack 11 below the product storage rack 11 having the product storage column 14, and is guided by the guide protrusion 51 directly below the lever member 22, so that the product falls in a serpentine manner down the dispensing passage 50. The product that has fallen in a serpentine manner down the dispensing passage 50 then rolls down the product chute 5 and is guided to the product removal outlet 3a through the product discharge outlet 4a.

When the guide protrusion 51 comes into contact with the product W1 falling through the dispensing passage 50, it is preferable that the guide protrusion 51 guides the product W1 to the vicinity of the lever penetration portion 222 of the lever member 22 directly below the guide protrusion 51. The reaction force (biasing force) of the spring member 26 that biases the lever member 22 is greater the closer it is to the lever penetration portion 222 through which the rotation drive shaft 30, which serves as the pivot axis of the lever member 22, penetrates, making it possible to effectively reduce the falling speed of the product W1.

In addition, in order to more effectively attenuate the impact of the product W1 that falls into the product chute 5, it is preferable that the guide protrusions 51 are formed so that the protruding height toward the dispensing passage 50 is greater the higher they are disposed on the upper side of the dispensing passage 50, and smaller the higher they are disposed on the lower side of the dispensing passage 50.

The control unit 60, which has stopped the drive motor 34, drives the drive motor 34 in the reverse direction. When the drive motor 34 drives in the reverse direction in this manner, the drive pulley 33 rotates counterclockwise as viewed from the right, and the transmission cable 32 is displaced, causing the rotation transmission member 31 to rotate counterclockwise as viewed from the right. When the rotation transmission member 31 rotates in this manner, the rotary drive shaft 30 also rotates around the central axis in a counterclockwise direction as viewed from the right. When the rotary drive shaft 30 rotates, the dog clutch 43 that fits the rotary drive shaft 30 also rotates counterclockwise as viewed from the right, and the pedal member 24 connected to the dog clutch 43 swings forward.

When the pedal member 24 swings forward, the stopper member 23, whose base portion 231b is pressed by the pedal body portion 242 of the pedal member 24, swings downward against the biasing force of the spring member 26, and then the stopper action portion 231 enters the stopper opening 214 and moves backward into the product storage passage 14a, and as a result, the pedal member 24 returns to the standby state. At this time, the pedal hook portion 242a of the pedal member 24 enters the slider recess 423 of the slider 42.

When the pedal member 24 returns to the standby state in this manner, the control unit 60 drives the clutch motor 41 in the reverse direction to slide the slider 42 to the right and position it away from the clutch motor 41.

When the clutch motor 41 is driven in reverse by the control unit 60, the control unit 60 performs the drive monitoring control process described above, just as when the clutch motor 41 is driven in forward direction.

As a result, the hook engaging portion 421b of the slider 42 engages with the pedal hook portion 242a, preventing the pedal member 24 from swinging even if a new product that is the most downstream product abuts against the pedal action portion 243, and the product is stored in the product storage passage 14a.

All of the rotation transmission members 31 are connected to the drive pulley 33 through the transmission cable 32, and therefore rotate in response to the drive of the drive motor 34. As a result, all of the rotary drive shafts 30 rotate. When the rotary drive shafts 30 rotate in this manner, the dog clutch 43 also rotates. However, in the dispensing mechanisms 20 other than the dispensing mechanism 20 described above, the pedal hook portion 242a of the pedal member 24 remains engaged with the hook engaging portion 421b, and the dog clutch 43 and the pedal member 24 are not connected. Therefore, the standby state of the dispensing mechanism 20 is maintained, and no products are dispensed from the other product storage columns 14.

As described above, according to the motor drive device 70 of the embodiment of the present invention, when the control unit 60 sends a drive command (forward rotation drive command or reverse rotation drive command) for the clutch motor 41 to the driver circuit 71 and receives an input from the binarization circuit 73 indicating that a current equal to or greater than a predetermined threshold has flowed through the clutch motor 41 after a predetermined reference time has elapsed, the operation of the clutch motor 41 is deemed to be complete and the drive (forward rotation drive or reverse rotation drive) of the clutch motor is stopped. This means that the operation of the clutch motor 41 can be stopped based on the magnitude of the current flowing through the clutch motor (DC motor) 41 without the need for a physical switch such as a microswitch, and the manufacturing costs can be reduced by eliminating the need for a physical switch.

In addition, because no physical switch is required, the space required for installing the physical switch and the space required for wiring are not required, resulting in a smaller size.

According to the drive device 70, the control unit 60 continuously inputs a signal representing a current less than a threshold value from the binarization circuit 73 during the time period from when the control unit 60 sends a motor drive command (forward rotation drive command or reverse rotation drive command) to the driver circuit 71 until a reference time has elapsed, thereby monitoring whether a steady current is continuously flowing through the clutch motor 41. Therefore, it is possible to effectively detect even when the power supply to the clutch motor 41 is cut off due to a power outage, for example.

The above describes a preferred embodiment of the present invention, but the present invention is not limited to this and various modifications can be made.

In the above-described embodiment, a binarization circuit 73 is provided to input to the control unit 60 a signal indicating that there is a current equal to or greater than a threshold value, as well as a signal indicating that there is a steady-state current less than the threshold value. However, in the present invention, the control unit may input the current that has flowed through the DC motor and determine whether or not there is a current equal to or greater than a threshold value.

In the above-described embodiment, in order to prevent the detection of the starting current in the drive monitoring control process, i.e., to prevent the binarization circuit 73 from inputting a signal that represents the input of a starting current that is equal to or greater than the threshold value, a predetermined reference time is set as a condition. However, in the present invention, without setting such a reference time, the control unit may ignore the first signal of a current input equal to or greater than the threshold value after sending the motor drive command, and may stop the drive of the DC motor upon the input of a second signal of a current input equal to or greater than the threshold value, assuming that the operation of the DC motor has been completed.

The configurations illustrated in the above-mentioned embodiments are merely functional schematics, and do not necessarily have to be physically configured as illustrated. In other words, the form of distribution and integration of each device and component is not limited to that illustrated, and all or part of them can be functionally or physically distributed and integrated in any unit depending on various usage conditions, etc.

In the above-described embodiment, an example was shown in which the motor drive device was applied to a vending machine, but in the present invention, the motor drive device may also be applied to a money processing device or other equipment.

41: clutch motor, 60: control unit, 70: drive device, 71: driver circuit, 73: binarization circuit.

Claims (1)

A motor drive device including a control unit that issues a drive command to a DC motor to drive the DC motor,
The control unit is
a driver circuit that supplies power to a terminal of the DC motor when a motor drive command is given from the control unit, and stops the supply of power to the terminal of the DC motor when a motor drive stop command is given from the control unit;
a binarization circuit which is connected to the driver circuit via a differential amplifier circuit, and which, when a current flowing through the DC motor and amplified by the differential amplifier circuit is equal to or greater than a preset threshold, determines that the motor is locked and sends a signal to that effect to the control unit, and, when a current flowing through the DC motor and amplified by the differential amplifier circuit is less than the threshold, determines that a steady-state current has been input and sends a signal to that effect to the control unit;
is connected to
Furthermore, the control unit, on condition that a reference time set to prevent detection of a starting current flowing through the DC motor has elapsed after giving the drive command , when it receives a signal indicating that a current equal to or greater than the threshold has been input from the binarization circuit, determines that the operation of the DC motor has been completed and stops driving the DC motor,
The motor drive device further comprises a control unit which monitors whether a steady-state current is continuously flowing through the DC motor by continuously inputting a signal representing a current less than a threshold value from the binarization circuit during the period from when the drive command is given until the reference time has elapsed .

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