Manual wheelchair inspection

A manual wheelchair is a common device that helps people with limited mobility (such as the elderly, disabled, or patients undergoing rehabilitation) to achieve daily mobility. It usually consists of a lightweight frame, two large rear wheels, two small front wheels, a seat, a backrest, pedals and other components. Manual wheelchairs are mainly pushed by the user himself or by others, and are often used for short-distance activities indoors and outdoors. How does a third-party inspection company inspect manual wheelchairs? What are the requirements and methods for inspecting manual wheelchairs?

Surface quality requirements for manual wheelchair inspection

Outer surfaces of parts and components: All outer surfaces that can be touched by hands should be flat and smooth, without sharp edges, burrs, or sharp corners, and each end of a pipe hole should be capped.

Chrome-plated parts: The main surface should be free of obvious coating defects such as bubbles, pores, roughness, cracks, and missing plating.

Galvanized parts: The main surface should be smooth, without nodules, roughness, zinc thorns, peeling, and residual solvent slag.

Anodized parts: The main surface should be uniform in color, without color difference and visible defects.

Painted surface: Should be flat and smooth, with uniform color, no exposed bottom, no bubbling, peeling or cracking, and no obvious scratches or dents.

Welding surface: should be smooth and flat, without weld nodules or pits, and should not have defects such as pores, cracks, slag inclusions, weld leaks, burn-throughs, etc.

Manual wheelchair assembly quality requirements

After the wheelchair is assembled, its various functions should be able to be used normally according to the manufacturer's instructions. All rotating and moving parts should move evenly and flexibly, with appropriate clearances, and there should be no sticking or looseness.

The spokes of each wheel should be adjusted evenly, and the spoke heads are not allowed to protrude beyond the nut.

The radial and end face runout of the assembled rim (wheel ring) should be less than 4mm, and the radial and end face runout of the hand ring should be less than 8mm.

The transmission mechanism should have a good fit, the meshing between the chain and the sprocket should be appropriately tight, there should be no chain falling off during transmission, and there should be no chain biting sound.

Folding manual wheelchairs should be flexible to fold and unfold, and should not be too loose or too tight.

The footrest of a foldable manual wheelchair should be easy to flip over and should not fall down by itself after being flipped up; the angle between the footrest and the footrest frame should be 86°~90° after being flipped down, and there should be no sagging on the inside.

Manual wheelchair dimensions requirements

The overall dimensions of a manual wheelchair should comply with the requirements in Table 1.

Table 1 Dimensions of manual wheelchairs

Unit is mm

Project Content	Manual three-wheeled wheelchair	Manual four-wheel wheelchair
		Outdoor	Indoor use
Total length L	≤2100	≤1200	≤1100
Overall width B	≤780	≤700	≤650
Total height H	≤1150	≤1400	≤1400

Manual wheelchair inspection quality requirements

The mass of a foldable manual wheelchair should not exceed 22 kg.

Manual wheelchair inspection performance requirements

The performance requirements for manual wheelchairs shall comply with the provisions of Table 2.

Table 2 Performance requirements for manual wheelchairs

Project Content	Standard requirements
	Manual four-wheel wheelchair		Manual three-wheeled wheelchair
	With wristband	No wristband
Wheel contact	All wheels except the lifting wheel should be firmly on the ground.	All wheels except the lifting wheel should be firmly on the ground.	—
Static stability (longitudinal tilt)	≥10°	≥10°	≥20°
Static stability (longitudinal tilt)	≥10°	≥10°	≥20°
Static stability (rolling)	≥10°	≥10°	≥15°
Hill holding performance	≥8°	≥8°	≥6°
Slide offset	≤350mm	≤350mm	—
Commutation width	—	≤1500mm	—
Turning diameter	—	≤1700mm	≤4000mm
Driving braking distance	—	—	≤1.5m

Manual wheelchair inspection test dummy

During the inspection, a test dummy is required. The specifications of the test dummy are shown in Table 3.

Table 3 Specifications of test dummies

Maximum quality of user kg	Test dummy quality kg
≤25	25
>25～50	50
>50～75	75
>75～100	100

According to the maximum user mass of the manual wheelchair specified by the manufacturer, select a test dummy with equal mass. If there is none, select a test dummy with a slightly larger load than the wheelchair (see Table 3).

Manual wheelchair inspection performance test method

Wheel contact test

Place the manual wheelchair on the platform, adjust the platform to a level surface, and after the manual wheelchair is weighted according to the indicated maximum user mass, place a piece of paper under any three wheels of the manual wheelchair and a 20mm±1mm pad under another wheel. The paper under the three wheels should not be pulled out.

Determination of sliding offset

Sliding test bench

The sliding test bench consists of a downhill surface and a test track plane. The connection between the downhill surface and the horizontal plane should have a smooth transition to avoid bumps when the manual wheelchair passes by; the lateral slope of the two planes should not exceed 0.1%. Draw a straight line perpendicular to the intersection of the downhill surface and the horizontal plane as the zero line on the downhill surface, and draw several straight lines with a spacing of 100mm on the horizontal plane and parallel to the zero line.

Inspection methods

After the manual wheelchair is weighted according to the maximum user mass indicated, it is pushed to the starting position of the downhill surface so that the right driving wheel coincides with the zero line, the casters are adjusted to the forward rolling direction, and the brakes are released. The manual wheelchair is allowed to slide down the downhill surface. Observe and record the distance that the right wheel of the manual wheelchair deviates from the zero line at the end of the test track.

This test was carried out three times, and the average of the three data was taken as the test result.

Determination of driving braking distance

Place a manual three-wheeled wheelchair on a cement road test track with a slope of 6°. The operator sits on the wheelchair and puts a counterweight on it. The wheelchair starts from the front edge of the seat 2m away from the bottom of the slope and rolls downward relying on potential energy. When the rear wheels reach the bottom of the slope, brake immediately and measure the distance traveled by the rear wheels after the wheelchair stops.

This test was carried out three times, and the average of the three data was taken as the test result.

Seat impact test

Place the manual wheelchair flat on the inspection table and allow a 5# football with a mass of 25kg±0.5kg and filled with iron sand (diameter 3.5mm) to fall freely from a height of 250mm to the seat.