Drawer position sensing latch operated switch assembly

[57] ABSTRACT

A drawer position sensing latch mechanism for generating an electrical pulse upon the latching of a cash drawer of a data terminal device. The mechanism includes a rotatable latch member and a switch actuating member slidably mounted on the latch member for conditioning the latching of the drawer upon movement of the drawer towards a closed position, means for urging the drawer to an open position which movement latches the drawer and closes a switch which generates an electrical pulse and includes a solenoid for rotating both the latch member and the switch actuating member to release the drawer for movement to an open position by the urging means.

Claims, 3 Drawing Figures

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PATENTED^! 71974

3,855,432

SHEET 1 OF 2

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PATENTED DEC 171974

3.855,432

SHEET 2 OF 2

FIG. 3

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3,855,432

DRAWER POSITION SENSING LATCH OPERATED SWITCH ASSEMBLY

BACKGROUND OF THE INVENTION

In modern data terminal or electronic cash register devices which are used in a checkout operation, the opening of the cash drawer prior to the disbursement of change is controlled by the operation of certain control keys on the keyboard of the terminal device. After a change operation, the cash drawer is required to be closed before the operation of the terminal device can continue. In meeting this requirement, prior cash drawer constructions have used a switch which is actuated as the drawer is moved into a latched position. It has been found, however, that the drawer may not be latched securely at the time of the switch operation and can subsequently be opened with the terminal indicating that the cash drawer is in a latched position. It is therefore a principal object of this invention to provide a latch mechanism which operates a switch only after the cash drawer is in a latched position. It is another object of this invention to provide a latch mechanism which can be released from the keyboard of the terminal device. It is a further object of this invention to provide a latching mechanism which is simple in operation and construction and therefore low in cost.

SUMMARY OF THE INVENTION

In accordance with the teachings of the present invention, there is provided a latch member pivotally mounted adjacent the cash drawer, a switch actuating arm slidably mounted on the latch member, the actuating arm engaging the arm of an associated switch in a non-actuated position, both the latch member and actuating arm having a latching portion for engaging the drawer upon movement of the drawer to a closed position and subsequently latching the drawer upon movement of the drawer to an open position, resilient means engaging the cash drawer and urging the drawer towards an open position, resulting in the drawer being latched by the latch member, and moving the actuating arm to trip the switch, and a solenoid engaging the latch member to rotate the latch member and the actuating arm to a position releasing the drawer to the action of the resilient means.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of the latch mechanism taken on line 1—1 of FIG. 2 showing the drawer in a position prior to its movement to a latched position.

FIG. 2 is a front sectional view of the latch mechanism taken on line 2—2 of FIG. 1.

FIG. 3 is a top sectional view of the latch mechanism taken on lines 3—3 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, there is shown a side view of the latch mechanism of the present embodiment and which includes the rear portion of the cash drawer. Included in the latch mechanism is an elongated latch member 20 rotatably mounted on a stud 21 secured to a bentover portion 22 of a bracket 23. Secured to the latch member 20 is a stud 24 which extends through both sides of the latch member 20 (FIG. 3). Rotatably secured to one end of the stud 24 is a link member 25 which in turn is rotatably secured to the armature 26 of a solenoid 27 by means of a stud 28. The solenoid 27 is mounted to the bracket 23.

Secured to the other end of the stud 24 is one end of a return spring 30, the other end of which is secured to a stud 31 mounted on the bent-over portion 22 of bracket 23. With this construction, the latch member 20 is capable of rotating in a clockwise direction as viewed in FIG. 1, about the stud 21 either by operation of the solenoid 27 or being moved by means, to be described hereinafter, attached to the end of the drawer. In either case, the clockwise movement of the latch member 20 is against the action of the spring 30 which allows the spring to return the latch member to its home position upon release of the latch member.

Slidably mounted on a stud 32 secured to the latch member 20 and the stud 21 is a switch actuating member 33, the rear end of which is U-shaped to form an actuating portion 34. This actuating portion 34 is engaged by the switch arm 35 of a snap action switch 36 secured to a bracket 37 mounted on bracket 23. The switch arm 35 when in a switch-open position normally positions the switch actuating member 33 in a rearward position with respect to the latch member 20. In the present embodiment, the switch arm 35 is biased in a rearward direction thereby sliding the switch actuating member 33 in a rearward direction. While other arrangements can be used, the only requirement of the construction is that the switch actuating member 33 be positioned with respect to the latch member 20 to allow for a movement in forward direction, which movement will move the switch arm 35 in a switch closing direction.

Both the latch member 20 and the spring actuating member 33 have a recessed portion 38 which functions to latch an L-shaped tab member 40 secured to the rear of the cash drawer 41 by means of screws 42. Also secured to the rear of the cash drawer are a pair of spring members 43, the other end of which are positioned over an associated stud 44 secured to the bracket 23.

In operation, the switch actuating member 33 is positioned in a rear position by the switch arm 35 when in a switch-open position. As the drawer 41 is moved toward a closed position, the L-shaped end of the tab member 40 will engage and cam both the latch member 20 and the switch actuating member 33 clockwise against the action of the spring 30. Further movement of the tab member 40 will allow the spring 30 to return the latch member 20 and the actuating member 33 to their home positions which positions the tab member 40 in the recessed portions 38 of the latch member 20 and switch actuating member 33. This movement of the drawer will compress the springs 43. Once the inward movement of the drawer stops, the springs 43 will move the drawer and the tab member 40 forward toward an open position. During this forward movement, the tab member 40 will engage the recessed portion 38 of the switch actuating member 33 moving the actuating member 33 a distance sufficient to rotate the switch arm 35 counterclockwise thereby closing the switch 36. This movement of the tab member will continue until it engages the recessed portion 38 of the latch member 20, thereby latching the drawer in a closed position.

Closing of the switch 36 will generate a signal to the terminal device that the cash drawer is latched and closed. To release the cash drawer to the action of the

3,855,432 spring 43, thereby opening the drawer, the solenoid 27 is momentarily energized during operation of the terminal device or through depression of an appropriate key on the terminal device resulting in the armature 26 moving in an upward direction. This movement will rock both the latch member 20 and the switch actuating member 33 clockwise, thereby releasing the tab member 40 allowing the drawer to move to an open position under the action of the springs 43. The solenoid will then be deenergized allowing the spring 30 to return the latch member 20 and the switch actuating member 33 to their home position.

It will be seen from this construction that the switch 36 is actuated only after the drawer is positioned so that it cannot fail to be latched in a closed position. The drawer is held in a latched position by the action of the spring 30 on the latch member 20 and the switch actuating member 33 thus requiring no electrical power to hold the cash drawer in a closed position. While the switch 36 is shown mounted perpendicular to the line of movement of the drawer, it is obvious that its position can be altered to accommodate the structural environment in which it is used. Numerous variations or modifications of the disclosed latching mechanism will be evident to those skilled in the art. Therefore, it is intended that the foregoing description of the invention and the illustrative embodiment be considered in the broadest aspects and not in a limiting sense.