The measure by which the tooth space of a gear exceeds the tooth thickness of the mating gear along the pitch circle. It is affected by both the center distance at which the gears operate, any eccentricity in the gears, and the variation in thickness of the teeth.
Term describing the amount of play between gears, or gear mesh. If too loose, the gear can slip, or strip the teeth. Too tight, and excessive wear is caused. !-- google_ad_client = "pub-8826792545718317"; google_ad_width = 468; google_ad_height = 60; google_ad_format = "468x60_as"; google_ad_channel ="0630871714"; google_page_url = document.location; google_color_border = "DFF2FD"; google_color_bg = "DFF2FD"; google_color_link = "0000CC"; google_color_url = "008000"; google_color_text = "000000"; //-- B. A. Threads Clearance and tapping drill sizes. more......
Rotational (arc) movement due to clearance betweeen transmission elements. In reducers, upon reversing direction of the input shaft, there is no immediate rotation of the output shaft
The motion error produced by direction reversing of the motion. It is presented as a constant hysteresis over the range and is an inherent problem in conventional motion translation mechanisms such as screw/nut, gears, trains and bearings, etc. Normally it is related to machining tolerance, wear, contact stiffness, temperature and loads, etc. nPoint's flexure motion translation mechanism and piezo actuator designs are inherently backlash free.
same as hysteresis but more commonly applied to mechanical systems
1 Superfluous motion in linked mechanical parts. 2 Rearward travel of the trigger beyond the point where the hammer or firing pin is released to discharge the weapon. 3 Failure of sight adjusting screws to move the sight positively the proper distance for each rotation of the adjusting screw.
The lost motion or looseness (play) between the faces of meshing gears or threads.
Looseness in a gear train, permitting uncontrolled movement between one gear and the driven gear.
Backlash (measured in degrees) is when a camera's Pan Tilt head cannot stop instantaneously, and is usually caused by excessive looseness in gears, pulleys, or other parts. Pre set PTZ surveillance cameras are rendered ineffectual by Backlash.
is the endplay between the gear teeth as the gear sets rotate relative to one another.
Backlash is the looseness between a lead screw and its nut so that turning the screw results in no movement of the milling machine table or other device.
Describes the play in the meshing of two gears. Too much backlash and the gears could slip or break the teeth, too little backlash could cause excess wear and tear. The common rule is the thickness of two sheets of paper for the right am ount of backlash.
a movement back from an impact
The relative movement of interlocked mechanical parts that occurs when motion is reversed.
similar to hysteresis but more commonly applied to mechanical systems
Free play in an axis assembly along the path of travel. The rotational shaft movement that results in no linear movement of the linear way.
(Mechanical Hysteresis) Backlash is defined as the amount (usually in microliters) of "play" or error in the mechanical drive of the pump assembly. This is only noticable when the motor armature changes direction. The error is the result of the clearance between the screw and nut portions of the drive. Properly accounted for with drive software, the backlash can be made insignificant to accuracy and precision.
The amount of free movement between a screw and nut
A condition in which a speed reducer's output shaft moves, but the input shaft remains motionless.
The non-responsive lost motion between a drive screw and its nut that occurs at the point of change in rotation direction.
Lost motion after reversing direction. This can be due to play in screw/nut fittings, gearheads, bearings, etc. Some manufacturers promote controllers with automatic backlash compensation adding the estimated amount of lost motion upon each reversal. A good solution in theory which is limited in practice because backlash varies with load, leadscrew position, temperature, deceleration, direction, wear etc. Backlash can lead to oscillation in closed loop set ups where the position sensor is directly attached to the part to be controlled. Backlash is not to be confused with hysteresis.
(usually said of gears) Total play measured in both directions. For example, timing gear backlash measures the total rotation of the timing gear when forced as far as possible in each direction with the crankshaft gear held fast.
The play or loose motion in an instrument due to the clearance existing between mechanically contacting parts.
The circumferential clearance between mating teeth.
is an error present in a pan tilt head due to the play in the mechanical components like gears, pulleys etc. This results in the Pan Tilt head not stopping instantaneously. This error is critical in pre set PTZ cameras and is measured in degrees.
The maximum magnitude of an input that produces no measurable output upon reversing direction. Typically the result of poor meshing between drivetrain components as with lead screw threads.
The excessive clearance between the meshing teeth of two gears.
The clearance or play between two parts, such meshed gears.
Rotational movement of the output shaft clockwise and counter clockwise, while holding the input shaft stationary. Usually expressed in thousandths of an inch and measured at a specific radius at the output shaft.
Backlash is the amount of clearance between mated gear teeth in a gear pair. While backlash is generally undesirable, some backlash is required to allow for lubrication, manufacturing errors, deflection under load and differential expansion between the gears and the housing .
