Automatic vending machine dispensing mechanism

A dispensing mechanism for an automatic vending machine includes a conveying mechanism to move merchandise toward a discharge passage, and a discharge control mechanism. The discharge control mechanism holds the merchandise and prevents the merchandise from falling into the discharge passage when the dispensing mechanism is off. The discharge control mechanism includes a control plate which is biased to contact and hold the merchandise, and a locking element which prevents the rotation of the control plate when the dispensing mechanism is off. The engagement between control plate and locking element is controlled by a solenoid which permits the rotation of the control plate during the dispensing operation.

TECHNICAL FIELD 
The present invention relates to an automatic vending machine. More 
particularly, the present invention relates to a device for preventing 
merchandise from falling off of the dispensing portion of a shelf. 
BACKGROUND OF THE INVENTION 
Many types of merchandise are sold in automatic vending machines which use 
different types of dispensing mechanisms. FIG. 1 is a partial sectional 
view of one type of vending machine 1 which is suitable for storing and 
dispensing, for example, paper packages of beverages. 
Storage chamber S is defined in vending machine 1, and at least one column 
C is disposed in storage chamber S to store merchandise. Column C includes 
outer frame 2 with merchandise discharge opening 2a, a plurality of 
shelves 3 extending backwardly within frame 2, and dispensing mechanism 4 
located on the lower portion of frame 2 opposite discharge opening 2a. 
Dispensing mechanism 4 dispenses merchandise individually through 
discharge opening 2a. Each shelf 3 is vertically movably connectable with 
each other. When the merchandise stored on one shelf is sold out, the 
adjacent shelf 3 vertically translates and replaces the empty shelf. 
Dispensing mechanism 4 includes merchandise conveying or pushing device 41 
having a pair of pushing elements 411 horizontally movable along shelf 3 
by motor 42 through endless chain elements 43, 44. Fall preventing device 
45 which operates as a discharge control mechanism prevents the 
merchandise from falling into discharge opening 2a. Fall preventing device 
45 is disposed on discharge opening 2a of column C and, as shown in FIG. 
2, includes attachment element 451 fixed on outer frame 2, control plate 
452 rotatably supported on attachment element 451 through support shaft 
453, and coil spring 454 which biases control plate 452 toward merchandise 
A. Therefore, merchandise stored on the lowermost shelf 3 is normally held 
between control plate 452 and pushing element 411, and is dispensed by the 
movement of pushing element 411. 
As explained above, the merchandise positioned for dispensing is held 
between control plate 452 of fall preventing device 45 and pushing element 
411. The merchandise is normally pushed away from the discharge passage 
and are held in position due to the recoil strength of coil spring 454 on 
control plate 452. However, if the force of control plate 452 acting 
against merchandise A is small, merchandise A may fall through discharge 
opening 2a into the discharge passage of vending machine 1 when vending 
machine 1 is shaken, hit, or tilted. If the force of control plate 452 is 
strong, this problem is eliminated. However, if the recoil strength of 
coil spring 454 is increased, the dispensing force of pushing element 411 
must be increased correspondingly to dispense merchandise. If the force of 
pushing element 411 is too strong, more than one unit of merchandise may 
be dispensed in one dispensing cycle. 
Furthermore, control plate 452 is always unlocked and is rotated easily by 
external forces. Thus, merchandise may be stolen by pivoting control plate 
452 from outside vending machine 1 through merchandise discharge opening 
2a. 
SUMMARY OF THE INVENTION 
It is a primary object of this invention to provide a dispensing mechanism 
for an automatic vending machine which smoothly dispenses without damaging 
merchandise. 
It is another object of this invention to provide a dispensing mechanism 
for an automatic vending machine having improved merchandise theft 
prevention. 
The invention is directed to an automatic vending machine including at 
least one column for storing and dispensing merchandise, a discharge 
opening and a dispensing mechanism. The column includes at least one shelf 
for supporting merchandise. The dispensing mechanism comprises a conveying 
mechanism for conveying the merchandise through the discharge opening and 
a discharge control mechanism for controlling the passage of the 
merchandise through the discharge opening. The discharge control mechanism 
comprises a control plate pivotally supported adjacent the discharge 
opening and a locking mechanism for releasably locking the control plate. 
The locking mechanism being movable from a first position wherein the 
locking means locks the control plate to a second position wherein the 
locking mechanism releases the control plate to permit rotation thereof. 
The discharge control mechanism further includes a control mechanism for 
controlling the position of the locking mechanism. 
Various additional advantages and features of novelty which characterize 
the invention are further pointed out in the claims that follow. However, 
for a better understanding of the invention and its advantages, reference 
should be made to the accompanying drawings and descriptive matter which 
illustrate and describes a preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIG. 3, a vending machine with a dispensing mechanism in 
accordance with the present invention is shown. The general structure of 
the vending machine is similar to that of FIG. 1. Like numerals indicate 
like parts. 
Automatic vending machine 1 has storage chamber S in which at least one 
column C is formed to store and dispense merchandise. Merchandise is 
delivered to discharge portion 1a of vending machine 1 from column C 
through discharge passage 1b. Dispensed merchandise can be removed from 
discharge portion 1a upon opening cover plate 1c. Column C includes outer 
frame 2 having merchandise discharge opening 2a at its lower front 
portion, a plurality of horizontal shelves 3 backwardly extending within 
frame 2, and dispensing mechanism 4 located on the lower portion of column 
C. 
Each shelf 3 is vertically movably connected with each other, with the 
lowermost shelf 3 engaged with dispensing mechanism 4. Dispensing 
mechanism 4 includes conveying or pushing mechanism 41 having a pair of 
pushing elements 411 driven by motor 42 through endless chain elements 43, 
44 and fall preventing device 10 which operates as a discharge control 
mechanism. Merchandise A stored on shelf 3 is dispensed individually by 
one pushing element 411. Pushing element 411 moves a horizontal distance 
sufficient to push one item of merchandise into discharge opening 2a. 
As shown in FIG. 3, discharge control mechanism 10 is disposed on the upper 
portion of discharge opening 2a on outer frame 2. Discharge control 
mechanism 10 has box-like case element 11 in which control plate 12 and a 
control device for control plate 12 are disposed. Control plate 12 is 
rotatably or pivotally supported on case element 11 through support shaft 
13 and extends into the upper portion of discharge opening 2a to contact 
merchandise A1. 
Control plate 12 is normally biased toward discharge opening 2a by the 
recoil strength of double torsion type coil spring 14. Coil spring 14 is 
disposed around support shaft 13. One end portion of coil spring 14 
contacts control plate 14 and the other end portion contacts support plate 
15 fixed on case element 11. The movement of control plate 12 is 
restricted by locking element 16. 
Locking element 16 is pivotally secured to case element 11 through shaft 17 
disposed above an upper portion of control plate 12. Locking element 16 is 
biased downwardly by coil spring 18. Locking element 16 is connected to 
lever 191 of solenoid 19 which controls the movement of locking element 
16. Locking portion 161 is formed on the lower portion of locking element 
16. Locking portion 161 includes notch 162 which engages slant portion 121 
formed on the upper portion of control plate 12. Thus, when solenoid 19 is 
off, lever 191 extends downwardly and locking portion 161 engages slant 
portion or projection 121 of control plate 12. Control plate 12 then is 
locked and can not pivot. When solenoid 19 is energized, lever 19 is moved 
upwardly and locking portion 161 disengages from slant portion 121 of 
control plate 12 so that control plate 12 can pivot away from the 
merchandise. 
Posture control plate 20 is disposed on the upper opening of case element 
11 facing outer frame 2. Posture control plate 20 controls the attitude of 
merchandise dispensed from discharge opening 2a causing merchandise A1 to 
fall bottom first, as shown by dotted and dashed line in FIG. 3. 
As explained above, the movement and locking of control plate 12 is 
controlled by solenoid 19. When vending machine 1 is operated, solenoid 19 
is energized and lever 191 pulls up locking element 16 to release locking 
portion 161 of locking element 16 from slant portion or projection 121 of 
control plate 12. Concurrently, pushing element 411, driven by motor 42, 
pushes merchandise A toward discharge passage 1b. When the force of 
pushing element 411 exceeds the recoil strength of coil spring 14, control 
plate 12 rotates to open discharge opening 2a to receive merchandise A. 
During the dispensing operation, the upper portion of merchandise A1 is 
disposed against posture control plate 20 to prevent forward movement, and 
the lower portion of merchandise A1 is moved forwardly by pushing element 
411. Thus, merchandise A1 falls bottom first through discharge opening 2a. 
After the dispensing operation is complete, the next piece of merchandise 
A2 is positioned adjacent discharge opening 2a. Coil spring 14 returns 
control plate 12 to its merchandise restricting position (shown in solid 
line in FIG. 4) and locking portion 161 of locking element 16 engages 
slant portion 121 of control plate 12 to lock control plate 12. Therefore, 
falling merchandise due to shaking, hitting, or tilting the vending 
machine is prevented, as is stealing merchandise by rotating the control 
plate from outside of the vending machine. Furthermore, the stored 
merchandise is less susceptible to damage, and is dispensed smoothly. 
Numerous characteristics and advantages of the invention have been 
described in detail in the foregoing description with reference to the 
accompanying drawings. However, the disclosure is illustrative only and 
the invention is not limited to the precise illustrated embodiment. 
Various changes and modifications may be effected therein by one skilled 
in the art without departing from the scope or spirit of the invention.