Housing¶

The main housing is a small cube with internal structure to hold the components. The housing contains an inverted stepper motor, which controls direction for the main housing. It also has internal structure to support the PCB. The top of the cube has a holder for the cards, and holds the roller and the motor for the roller. The main housing also has the buttons and LCD integrated into one face.

Main case¶

This case is laser cut from 4mm MDF. It is a small cube, with width and depth of 110mm (internally). This case was designed in Autodesk fusion.

I utilized the manufacturing space in Fusion, so that when faces are modified the flat versions are updated. These flat versions allow for easy export to laser cut. The case includes holes for the three buttons, a cutout space for the LCD, and mounting holes for the inverted stepper. I did go through several iterations. Among other things, I needed to move the motor to not conflict with internal component positioning and change to make the position motor from a Nema 14 to Nema 17.

Fusion design for the main case.

Internal housing¶

There are a number of components to create the structure to hold internal components and the structure to hold and move the cards. I did a lot of prototyping, and also made parts that stacked. I did need to change size and arrangements of the pieces, so having them built from multiple pieces helped with more rapid times. All these internal pieces were 3D printed.

Riser table

Within the case, the lowest piece is a riser. In an earlier design, I was working with a Nema 14 motor. For more turning power, I switched to an inverted Nema 17, which required more clearance. I added a riser to gain additional space.

Fusion design for the riser.

PCB table

Sitting on top of the riser table is a table that holds the PCB. It has a hole within to allow the wiring from the buttons and the lower stepper to pass through. The buttons on the case are lower than the top of this table.

Table where PCB rests. Hole for wires to pass

Fusion design for the PCB table

Roller table

Resting on the PCB table is a table which is level with the top of the main case. This has several aspects. The table has a cutout for the roller. It also has notches for the card holder to latch onto. It also has a mount for the roller motor. There are holes to hold the roller in place with the motor and a pin.

Fusion design for the roller table

Card holder frame

The cards are positioned with a frame that is slightly larger than a deck of cards. With tabs on the bottom, it latches onto the roller table. It also has a mounting tower for the pressure arm. On this short tower, there are places to attach springs which apply pressure. This frame creates a small slot. The upper cards of a deck are held back by the frame, and only small space is left for the bottom cards.

/// Frame to hold cards ///

Fusion design for the card holder frame

Pressure arm

To create pressure for the cards against the roller, there is an arm. The arm is printed in duplicate, which assemble together. One end goes through the hole in the tower on the card holder frame. The other holds the foot which applies pressure. A pin goes through the central hole, which is the position to attach the other end of the springs.

Fusion design for the pressure arm

Roller

The roller is 3D printed. The circumfrence is designed for one rotation to be the length of a typical playing card (3 1/4 inch). The roller has 5mm holes for the mounting pin and the roller motor. For the roller end, there is place to put a M4 nut and bolt to hold the roller against the stepper motor pin. The roller has small grooves to hold some rubber bands in place.

Fusion design for the roller

Outside frame

To improve the overall appearance, and to hold the case together, I made an external frame. This has a small lip to hold the box at the top, and there are legs which clip to the base along the four corners.

Fusion design for the external frame

LCD frame

As part of the mount for the LCD, a small frame was made to put on the outside of the main case. This covers a larger hole made to accomodate pins on the LCD circuit board. This frame has brass screw mounts melted into place on the back side. This allows M4 screws to mount the frame to the case while holding the LCD

Fusion design for the LCD frame

In total¶

Together, these make the internal housing and key pieces for dealing the cards