Air flow switch holder - Revision history

James: adjusted height and position of filler block between switch holder and wafer flanges to unblock hinge pin hole

2017-05-07T04:22:02Z

adjusted height and position of filler block between switch holder and wafer flanges to unblock hinge pin hole

← Older revision		Revision as of 04:22, 7 May 2017
Line 66:		Line 66:
	translate([sfw/2+thick/2,0,thick]) rotate([-90,0,0]) cylinder(d1=shd1.6,d2=0,h=shd2);//up direction arrow head		translate([sfw/2+thick/2,0,thick]) rotate([-90,0,0]) cylinder(d1=shd1.6,d2=0,h=shd2);//up direction arrow head
	translate([sfw/2+thick/2,0,thick]) rotate([90,0,0]) cylinder(d=shd0.8,h=shd2); //up direction arrow shaft		translate([sfw/2+thick/2,0,thick]) rotate([90,0,0]) cylinder(d=shd0.8,h=shd2); //up direction arrow shaft

	}		}
	translate([0,0,-thick/2]) intersection(){ //bore		translate([0,0,-thick/2]) intersection(){ //bore
Line 84:		Line 83:
	union(){		union(){
	cube([thick,shp+3shd,3shd],center=true);//mount flange		cube([thick,shp+3shd,3shd],center=true);//mount flange
	color("blue") translate([0,0,-srh/2-shd/2]) cube([thick,shp+3*shd,srh],center=true); //support for mount flange		color("blue") translate([0,0,-srh/2-flap/4+thick/2-3shd/4]) cube([thick,shp+3shd,srh+flap/2-thick-3*shd/2],center=true); //support for mount flange
	translate([-thick/2,0,-shd~~1.5~~]) cylinder(d2=shd1.2,d1=0,h=shd*1.5);//flow direction arrow head		translate([-thick/2,0,-shd2]) cylinder(d2=shd1.6,d1=0,h=shd*2.0);//flow direction arrow head
	translate([-thick/2,0,0]) cylinder(d=shd0.6,h=shd1.5); //flow direction arrow shaft		translate([-thick/2,0,-shd/2]) cylinder(d=shd0.8,h=shd2.0); //flow direction arrow shaft
	}		}
	for (dy=[-shp/2,shp/2]) {		for (dy=[-shp/2,shp/2]) {
Line 103:		Line 102:
	}		}
	translate([0,hph,flap/2]) rotate([0,90,0]) cylinder(d=1,h=bcd+4*bhd,center=true); //hinge pin axis		translate([0,hph,flap/2]) rotate([0,90,0]) cylinder(d=1,h=bcd+4*bhd,center=true); //hinge pin axis
	}</nowiki>		}
			</nowiki>
	</pre>		</pre>
	[[Category: CheapChineseLaser]]		[[Category: CheapChineseLaser]]

James: changed value of switch roller height (srh) and elevation of switch holder

2017-05-07T01:51:52Z

changed value of switch roller height (srh) and elevation of switch holder

← Older revision		Revision as of 01:51, 7 May 2017
Line 49:		Line 49:
	shd=2; //switch hole diameter		shd=2; //switch hole diameter
	shp=10; //switch hole pitch, i.e. center to center spacing of mounting holes on microswitch		shp=10; //switch hole pitch, i.e. center to center spacing of mounting holes on microswitch
	srh=8; //switch roller height, i.e. height above switch hole centerline where switching action occurs		srh=12; //switch roller height, i.e. height above switch hole centerline where switching action occurs
	sbw=6; //switch body width		sbw=6; //switch body width
	nfw=5; //nut face width		nfw=5; //nut face width
Line 80:		Line 80:
	translate([0,hph,flap/2]) rotate([0,90,0]) cylinder(d=1,h=bcd+4*bhd,center=true); //hinge pin axle hole		translate([0,hph,flap/2]) rotate([0,90,0]) cylinder(d=1,h=bcd+4*bhd,center=true); //hinge pin axle hole
	} //end of wafer body		} //end of wafer body
	translate([-thick/2-sfw/2,0,~~thick~~+srh]){ //switch holder		translate([-thick/2-sfw/2,0,flap/2+srh]){ //switch holder
	difference(){		difference(){
	union(){		union(){

James: added newlines to initial comment to prevent text running off the edge of the screen

2017-05-05T23:28:56Z

added newlines to initial comment to prevent text running off the edge of the screen

← Older revision		Revision as of 23:28, 5 May 2017
Line 17:		Line 17:
	exhaust airflow detector		exhaust airflow detector
	safety interlock for cheap Chinese laser at Hac DC		safety interlock for cheap Chinese laser at Hac DC
	This switch is a lug style wafer for insertion between the exhaust collector and the exhaust nozzle on the back of the laser chassis. When the exhaust fan is running and air is flowing the switch will operate to allow the laser to fire. This switch is upstream of the exhaust fan so air will leak into the exhaust stream, not exhaust leaking out into room air.		This switch is a lug style wafer for insertion between the exhaust collector and the exhaust nozzle on the back of the laser chassis.
			When the exhaust fan is running and air is flowing the switch will operate to allow the laser to fire. This switch is upstream of
			the exhaust fan so air will leak into the exhaust stream, not exhaust leaking out into room air.
	James Sullivan		James Sullivan
	5-5-17, v2		5-5-17, v2

James: added link to stl file

2017-05-05T23:27:45Z

added link to stl file

← Older revision		Revision as of 23:27, 5 May 2017
Line 11:		Line 11:
	#Thickness increased from 3 to 5 mm		#Thickness increased from 3 to 5 mm
	#Wire holes relocated 180°		#Wire holes relocated 180°
			You can find the stl file here [[File:Airflow-switch.stl]]
	<pre>		<pre>
	<nowiki>		<nowiki>

James: version 2

2017-05-05T23:23:17Z

version 2

Show changes

James: added points for improvement

2017-05-03T04:47:54Z

added points for improvement

← Older revision		Revision as of 04:47, 3 May 2017
Line 1:		Line 1:
	This is the OpenSCAD code to create a wafer air flow sensor (and backflow preventer) to hold a microswitch to stop the laser from firing if the exhaust flow stops. Dimensions have been set to match the exhaust nozzle. The current version of the nacelle doesn't quite match, even though the nozzle was reverse engineered from it.		This is the OpenSCAD code to create a wafer air flow sensor (and backflow preventer) to hold a microswitch to stop the laser from firing if the exhaust flow stops. Dimensions have been set to match the exhaust nozzle. The current version of the nacelle doesn't quite match, even though the nozzle was reverse engineered from it.

			This was printed on 5/1 and it has some issues.
			#The arms which hold the switch body interfere with the flap plate.
			#The flap plate axis of rotation could be lowered to improve the balance.
			#The thickness of the wafer can be increased to reduce the warpage of the piece.

	<pre>		<pre>

James: added

 tags and category

2017-05-02T00:02:27Z

added <pre> tags and category

← Older revision		Revision as of 00:02, 2 May 2017
Line 1:		Line 1:
	This is the OpenSCAD code to create a wafer air flow sensor (and backflow preventer) to hold a microswitch to stop the laser from firing if the exhaust flow stops. Dimensions have been set to match the exhaust nozzle. The current version of the nacelle doesn't quite match, even though the nozzle was reverse engineered from it.		This is the OpenSCAD code to create a wafer air flow sensor (and backflow preventer) to hold a microswitch to stop the laser from firing if the exhaust flow stops. Dimensions have been set to match the exhaust nozzle. The current version of the nacelle doesn't quite match, even though the nozzle was reverse engineered from it.

			<pre>
	<nowiki>		<nowiki>
	/*		/*
Line 92:		Line 93:
	}		}
	</nowiki>		</nowiki>
			</pre>
			[[Category: CheapChineseLaser]]

James: updated introductory text to state dimensions match nozzle

2017-04-21T03:40:17Z

updated introductory text to state dimensions match nozzle

← Older revision		Revision as of 03:40, 21 April 2017
Line 1:		Line 1:
	This is the OpenSCAD code to create a ~~waffer~~ flow sensor to hold a microswitch to stop the laser from firing if the exhaust flow stops. ~~None of the dimensions~~ have been set ~~here yet~~.		This is the OpenSCAD code to create a wafer air flow sensor (and backflow preventer) to hold a microswitch to stop the laser from firing if the exhaust flow stops. Dimensions have been set to match the exhaust nozzle. The current version of the nacelle doesn't quite match, even though the nozzle was reverse engineered from it.

	<nowiki>		<nowiki>

James: adjusted dimensions to match exhaust nozzle, added clearance to flap

2017-04-21T03:26:39Z

adjusted dimensions to match exhaust nozzle, added clearance to flap

← Older revision		Revision as of 03:26, 21 April 2017
Line 7:		Line 7:
	This switch is a lug style wafer for insertion between the exhaust collector and the exhaust nozzle on the back of the laser chassis. When the exhaust fan is running and air is flowing the switch will operate to allow the laser to fire. This switch is upstream of the exhaust fan so air will leak into the exhaust stream, not exhaust leaking out into room air.		This switch is a lug style wafer for insertion between the exhaust collector and the exhaust nozzle on the back of the laser chassis. When the exhaust fan is running and air is flowing the switch will operate to allow the laser to fire. This switch is upstream of the exhaust fan so air will leak into the exhaust stream, not exhaust leaking out into room air.
	James Sullivan		James Sullivan
	4-19-17		4-20-17
	OpenSCAD version 2015.03-1		OpenSCAD version 2015.03-1

			--dimensions from mating exhaust nozzle--
			nid=60; //nozzle inner diameter
			nod=80; //nozzle outer diameter
			mod=100; //maximum outer diameter
			sh=30; //step height
			sw=5; //step width
			oah=50; //over-all height
			tlw=3; //top ledge width
			bcd=46.8*2; //bolt circle diameter
			bhd=3.6; //bolt hole diameter
			fw=12; //foot width
			fh=15; //foot height
			fod=108; //foot outside dimension, from outside edge to outside edge
			fid=(nid+nod)/2;//foot inside dimension, from inside edge to inside edge

	*/		*/
	fid=75; //flange inner diameter		fid=60; //flange inner diameter, same as nid
	fod=95; //flange outer diameter		fod=80; //flange outer diameter, same as nod
	bhd=5; //bolt hole diameter		bhd=3.6; //bolt hole diameter
	bcd=~~115~~;//bolt circle diameter		bcd=93.6;//bolt circle diameter
	hph=10; //hinge pin height above center line, i.e. butterfly offset. Reduce to make switch more sensitive. Increse to make switch more stable.		hph=10; //hinge pin height above center line, i.e. butterfly offset. Reduce to make switch more sensitive. Increse to make switch more stable.
	sfw=sqrt(fidfid-4hph*hph); //switch flap width		sfw=sqrt(fidfid-4hph*hph); //switch flap width
Line 24:		Line 40:
	thick=3; //thickness of flange		thick=3; //thickness of flange
	$fn=80;		$fn=80;
	~~rotate([90,0,0]){~~
	difference(){		difference(){
	union(){		union(){
Line 68:		Line 84:
	}		}

	translate([0,~~hph~~+~~105,thick~~/2~~]) rotate([-15,0~~,0~~]) translate([0,-hph,-thick/2~~]) difference(){ //flap disk		translate([0,fid/2+bcd/2+bhd*2,0]) difference(){ //flap disk
	intersection(){ //bore		intersection(){ //bore
	cylinder(d=fid, h=thick); //circular top and bottom		cylinder(d=fid-0.5, h=thick); //circular top and bottom
	cube([sfw,fod,thick*2],true); //vertical left and right		cube([sfw-0.5,fod,thick*2],true); //vertical left and right
	}		}
	translate([0,hph,thick/2]) rotate([0,90,0]) cylinder(d=1,h=bcd+4*bhd,center=true); //hinge pin axis		translate([0,hph,thick/2]) rotate([0,90,0]) cylinder(d=1,h=bcd+4*bhd,center=true); //hinge pin axis
	}
	}		}
	</nowiki>		</nowiki>

James: created page.

2017-04-21T03:11:16Z

created page.

New page

This is the OpenSCAD code to create a waffer flow sensor to hold a microswitch to stop the laser from firing if the exhaust flow stops. None of the dimensions have been set here yet.

<nowiki>
/*
exhaust airflow detector
safety interlock for cheap Chinese laser at Hac DC
This switch is a lug style wafer for insertion between the exhaust collector and the exhaust nozzle on the back of the laser chassis. When the exhaust fan is running and air is flowing the switch will operate to allow the laser to fire. This switch is upstream of the exhaust fan so air will leak into the exhaust stream, not exhaust leaking out into room air.
James Sullivan
4-19-17
OpenSCAD version 2015.03-1
*/
fid=75; //flange inner diameter
fod=95; //flange outer diameter
bhd=5; //bolt hole diameter
bcd=115;//bolt circle diameter
hph=10; //hinge pin height above center line, i.e. butterfly offset. Reduce to make switch more sensitive. Increse to make switch more stable.
sfw=sqrt(fid*fid-4*hph*hph); //switch flap width
shd=2; //switch hole diameter
shp=10; //switch hole pitch, i.e. center to center spacing of mounting holes on microswitch
srh=8; //switch roller height, i.e. height above switch hole centerline where switching action occurs
sbw=6; //switch body width
nfw=5; //nut face width
nt=1; //nut thickness
thick=3; //thickness of flange
$fn=80;
rotate([90,0,0]){
difference(){
union(){
cylinder(d=fod,h=thick); //wafer body
hull(){ //horizontal lugs
translate([bcd/2,0,0]) cylinder(d=3*bhd, h=thick);
translate([-bcd/2,0,0]) cylinder(d=3*bhd, h=thick);
}
rotate([0,0,90]) hull(){ //vertical lugs
translate([bcd/2,0,0]) cylinder(d=3*bhd, h=thick);
translate([-bcd/2,0,0]) cylinder(d=3*bhd, h=thick);
}
}
translate([0,0,-thick/2]) intersection(){ //bore
cylinder(d=fid, h=2*thick); //circular top and bottom
cube([sfw,fod,thick*4],true); //vertical left and right
}
for (angle=[0:90:270]){ //bolt holes in lugs
rotate([0,0,angle]) translate([bcd/2,0,-thick/2]) cylinder(d=bhd,h=thick*2);
}
for (angle=[55:5:65]){ //wire holes through flange
translate([0,0,thick/2]) rotate([0,90,angle]) cylinder(d=1,h=bcd/2);
}
translate([0,hph,thick/2]) rotate([0,90,0]) cylinder(d=1,h=bcd+4*bhd,center=true); //hinge pin axle hole
}
translate([0,fid/2-shp-3*shd,0]){ //switch holder
difference(){
union(){
translate([sbw/2,0,0]) cube([thick,shp+3*shd,3*shd]); //left mount flange
translate([-sbw/2-thick,0,0]) cube([thick,shp+3*shd,3*shd]);//right mount flange
}
translate([-sbw/2-3/2*thick,3/2*shd,3/2*shd]) rotate([0,90,0]) cylinder(d=shd,h=sbw+3*thick); //lower bolt hole
translate([-sbw/2-3/2*thick,shp+3/2*shd,3/2*shd]) rotate([0,90,0]) cylinder(d=shd,h=sbw+3*thick);//upper bolt hole
for (angle=[0:120:240]){
translate([-sbw/2-thick,3/2*shd,3/2*shd]) rotate([angle,0,0]) cube([nt*2,nfw,nfw/sqrt(3)],center=true); //lower nut socket
translate([-sbw/2-thick,shp+3/2*shd,3/2*shd]) rotate([angle,0,0]) cube([nt*2,nfw,nfw/sqrt(3)],center=true); //upper nut socket
}
}
translate([sbw/2+thick,shp/2+shd*1.5,shd*1.5]) cylinder(d1=shd*1.2,d2=0,h=shd*1.5); //flow direction arrow head
translate([sbw/2+thick,shp/2+shd*1.5,0]) cylinder(d=shd*0.6,h=shd*1.5); //flow direction arrow shaft
translate([-sbw/2-thick,shp/2+shd*1.5,shd*1.5]) cylinder(d1=shd*1.2,d2=0,h=shd*1.5);//flow direction arrow head
translate([-sbw/2-thick,shp/2+shd*1.5,0]) cylinder(d=shd*0.6,h=shd*1.5); //flow direction arrow shaft
}

translate([0,hph+105,thick/2]) rotate([-15,0,0]) translate([0,-hph,-thick/2]) difference(){ //flap disk
intersection(){ //bore
cylinder(d=fid, h=thick); //circular top and bottom
cube([sfw,fod,thick*2],true); //vertical left and right
}
translate([0,hph,thick/2]) rotate([0,90,0]) cylinder(d=1,h=bcd+4*bhd,center=true); //hinge pin axis
}
}
</nowiki>