Revision as of 21:19, 3 May 2015

Introduction

Prototype 2 of the MicroTrac. See Power Cube Genealogy for Power Cube.

Parts Library

Power Cube v7s

Component Area	Part	Qty	Price	Weight
Cage	Hydraulic Pump .677 cu in, 10.1 gmp @3600 RPM, 3000 PSI max, 4000 RPM max	1	$185	9 lbs
Cage	NT filter or SC filter	1	$17	2 lbs
Cage	or type E coupler half 1/4" key 2.5" o'all long	2	$9.86	1 lbs
Control	3 spool valve (about 1900-3400 PSI relief setting)	1	$220	35 lbs
	Drive Wheel	1
	17.5 HP gas engine	1		60 lbs
	Hydraulic Reservoir	1		10 lbs
	Battery	1	$23	20 lbs
Frame Metal	2x2x1/8" square tube 29" long	6	$30.95	44 lbs
Frame Metal	2x2" square tube 24" long	4	$17	24 lbs
Frame Metal	2x2" square tube 20" long	8	$28.46	40 lbs
Frame Metal	2x2" square tube 7" long	2	$2.49	4 lbs
Frame Metal	7x25" plate 1/4" thick	1
Optional/Unused	L095 coupler half 1" shaft 1/4" key 1-1/16" long	1	$15.28	1 lbs
Optional/Unused	L095 hytex coupler insert	1	$18.29	0 lbs
Optional/Unused	L095 coupler half 3/4" shaft 3/16" key 1-1/16" long or 5/8"	1	$15.28	1 lbs
Total			$582	251 lbs

Design

Goals

41" (1041.4mm) width

Design Proposals

Tracks with rotors

draft File:Ose-microtrac-20150429.skp

laying out ideas for idler and motor

PC7s Modification Suggestions

Split the controls apart from the hydraulic connections. This will separate the throttle and keyswitch into a control panel that can be easily relocated anywhere on the PC7s frame. This will allow all controls for to be grouped together. The hydraulic connections can be streamlined for more direct fluid flow and thus less energy loss.

Here is a suggested panel for PC7s controls:

Several items will need to be connected to the frame that do not require full structural strength (ex: Control Panel). Bolting these to the frame are a challenge using conventional nut and bolt hardware. It is simplified by using special nuts with conventional bolts, such as the two shown below:

Source: Floating Nut Retainer

Source: ND Weld Nut

These can be welded, but will work without welding.

Past Design Work

Graham_Microtrac

Tracks

Track Proposal Google Drive Folder

Reference Works

Toro makes a series of comparable machines, called the "Dingo". Toro publishes information about them, which make excellent references into their design and operation:

Toro Dingo Website

Toro uses a dual gear pump in Model 323, directly coupled to the engine shaft. One pump is 4 GPM and the other is 10.8 GPM. It can switch from one pump to the other for higher speed or higher torque. They say the low flow setting is good for training.

They use two hubs and two rubber disc couplers for power transmission - we haven't use this setup, but I've seen them before

@@ Line 62: / Line 62: @@
 ===PC7s Modification Suggestions===
+* Split the controls apart from the hydraulic connections. This will separate the throttle and keyswitch into a control panel that can be easily relocated anywhere on the PC7s frame. This will allow all controls for to be grouped together. The hydraulic connections can be streamlined for more direct fluid flow and thus less energy loss.
+Here is a suggested panel for PC7s controls:
+[[Image:PC7sControls.jpg PC7s Control Panel]]
 * Several items will need to be connected to the frame that do not require full structural strength (ex: Control Panel). Bolting these to the frame are a challenge using conventional nut and bolt hardware.  It is simplified by using special nuts with conventional bolts, such as the two shown below: