In bowling, a pinsetter, or pinspotter, was originally a person who would manually reset bowling pins in their correct position, clear fallen pins, and return bowling balls to the players. Probably due to the nature of the work (low-paid, often part-time, manual labor which most frequently took place during evenings) many pinsetters were teenaged boys, and thus pinboy is another name used to describe the job. In 1936 Gottfried Schmidt invented the mechanical pinsetter while with the AMF firm, which largely did away with pinsetting as a manual profession, although a very small number of bowling alleys do still use human pinsetters. While humans usually no longer set the pins, a pinchaser, or in slang pin monkey, often is stationed near the equipment to ensure that it is clean, working properly, and to unjam minor pin jams.
Many pinsetters are integrated with electronic scoring systems of varying sophistication. While many pinsetters have a manual reset button to use in case the pinsetter does not automatically activate at the correct time, other types have no automatic tracking of the state of the game, and are always manually activated.
The design of the machines varies. Several types of bowling make use of different designs for machines due to the different size and shape of the pins and balls.
A very common design for ten-pin bowling (the Brunswick Model A, dating from 1955, as well as the developed A2 and JetBack versions of it) pinsetters work as follows.
First, the balls and pins are pushed off the end of the lane onto a shaking board the width of the lane. This "shaker" transfers the ball and pins to the rear of the pit, behind the lane's pindeck. Two large spinning wheels are situated with their common axis along the bowling lane. The ballwheel is the one closer to the bowler and is smooth on the inside; the pin-wheel (or pin elevator) has many pockets which capture the pins.
When a ball rolls back to the ballwheel, friction lifts the ball up to the side where it catches on two lift rods covered with a rubber material. Wedged in between, the ball is rolled up. When it gets to the top, it gets deposited onto a metal track which usually leads underground being pushed along by a long accelerator belt, and finally the ball is pushed up by two pulleys located at the head of the ball return track which is where it's deposited.
When a pin rolls back, the smaller diameter of the pin allows it to fall rearwards through the ball return wheel. Still being shaken by the board, it bounces around until it lands in a pocket in the pinwheel. It may be seated in the pinwheel head-first or base-first. The wheel brings the pin to the top and drops it into a metal tray, called a "turnaround pan". It's shaped somewhat like a scoop, with the lip of the scoop facing the bowler. The weight of the pin's body makes it drop into the pan base-first. It orients the pin so that its base is coming toward the bowler. From there a conveyor belt lifts the pin up, letting it slide into one of ten spots in a metal basket called the "turret". (This turret is situated just above the triangular-shaped deck, which the bowler can see when the pins are actually set.) When a pin lands in an empty location in the turret, the turret rotates (or "indexes") so that the next pin will land in the next location, with the center of the turret also having an open location for the number 5-pin, at the center of the complete rack. Once the turret is full, the machine waits until it needs to re-set the pins. At that point, all ten pins are simultaneously dropped out of the turret into the spotting table, which lowers them all onto the lane.
This style of machine is typically loaded with 20 pins, though most proprietors normally put in 22 pins to facilitate quicker loading and faster operation of the pinsetter, especially in cases where the bowler(s) make two strikes in quick succession. Adding a couple of extra pins does not put undue stress on the machine, but adding more than that is not advisable due to damage that can occur to the machine.
Other types of pinsetters are as follows:
Bowl Mor pinsetters have a depressed pit approximately 14" long at the end of the bowling lane, placed about 4" below the level of the lane surface, with a curtain behind it, hanging past the lane surface but not touching the bottom of the pit. The curtain arrests the backwards motion of struck balls and pins, so that they fall onto the pit. When a reset takes place, a sweeper bar descends and sweeps the pins and balls off the lane, through the depressed area, and past the curtain and onto a rotating turntable. Here, pins and balls separate, being spun off the turntable by centrifugal force into the elevators.
An elevator composed of a rotating rack of open frames (similar to an industrial toaster) catches the pins and hauls them towards the top of the machine, and then turns 90 degrees to bring the pins horizontally across, bringing the pins past ten conveyors each wide enough to hold pins in a lengthwise orientation. The pins fall off the end of the conveyors into tubes. Once the sweeper has moved out of the way to its resting position, the tubes are dropped to the end of the alley and release a set of pins, and are then retracted.
A separate elevator next to the turntable transports the balls to the ball return system, which has a near-vertical ramp which the balls roll down to gain enough momentum for them to roll through a trough back up the alley, coming to rest in a rack next to the approach area where players can grab them. Bowl Mor pinsetters are stocked with 24 to 27 pins, and are deemed substantially more reliable than typical Ten-pin bowling pinsetters. Most parts of the machine are driven by chains or belts. A Bowl Mor unit weighs approximate 1450 pounds, and draws 24 amps at 110 volts from three-wire 110-220 volt service mains. The ICBA lists the cost of a refurbished Bowl Mor unit at approximately $5000.
Free-fall 5-pin pinsetters work in a way similar to their ten-pin counterparts, although they do not engage automatically when a ball is bowled or pin knocked down. When the player pushes their "Reset" button, the machine lowers a guards, lifts standing pins and sweeps away the downed pins. If it does not recognize any standing pins, it will set up a new set for the next frame. Unlike tenpin, balls and pins are picked up in the same elevator or conveyor and are separated at the top of the machine.
Hard belly duckpin is popular in the northeastern United States. It uses a pinsetter that is known as the Sherman. The Sherman features conveyor belts at the ends of the gutters that move fallen pins to the pit. Its sweep is located on the right side, vertical "kickback" panel of the lane and pivots 180 degrees (much like a fence gate) to clear pins. The pin table always handles the pins by the neck. A new rack of pins is created with a moving magazine that is shaped like a pin triangle. When the magazine is loaded, the pin table picks the pins out of the magazine and sets them on the lane.
Soft belly or rubber band duckpin is played in Quebec. Most of these bowling centers use a string type pinsetter similar to five pin. Apart from five-pin, rubber band duckpin is the only bowling variant that currently sanctions string type pinsetters. The free-fall machine for this sport features a rotating pit floor similar to a Bowl-Mor, conveyor belts in the gutters, an elevator similar to the Brunswick GSX, a turret similar to the A-2, and a rather flat looking pin table. The sweep is similar to the candlepin Bowl-Mor.