Illustration of an early massage chair design by Roland Labbe.
Imagine this scenario: you come home after a long day. Your back is stiff, your shoulders ache and your feet are throbbing with pain. You slip off your shoes, sit back in a reclining chair and pick up a remote. But you’re not about to watch television — you’re telling your chair about all your aches and pains. Then your chair gives you a massage.
Robotic massage chairs have been around for a few decades. In the United States, they’re luxury items that can cost several thousand dollars. While massage chairs have a relatively small market in the United States, that’s not the case everywhere. Many Web sites claim that massage chairs are much more common in Japan — some sites estimate that more than 20 percent of Japanese households have one.
The idea behind a robotic massage chair is pretty simple. A device on or inside the chair provides the person sitting in it the sensation of receiving a massage. Some chairs only have simple vibrating elements. Others contain complex machinery designed to mimic a human massage therapist’s techniques. All of them are designed to provide comfort and relief to weary people with disposable income.
While many of the massage chairs on the market rely on a mechanical approach, inventors have come up with several other techniques to perfect the massage chair. Some have created designs that use water to massage away tension and stress. Others use a series of airbags to squeeze muscles and promote blood circulation. Several massage chair manufacturers use a combination of technologies in their products.
How do these machines work? Sit back, relax and set your chair to “shiatsu” as we take you through step by step. Let’s start with the mechanical approach.
EASY MASSAGE CHAIRS
In 1948, Roland A. Labbe filed a patent application for a massage chair. Labbe’s design consisted of a stool mounted on a pedestal. A metal frame attached to the back section of the pedestal. Labbe designed the chair to vibrate and stretch the person sitting in the chair as a means to relieve stress, tension and pain. He also thoughtfully designed the ability for the chair to accept attachments that could provide other forms of massage. Compared to today’s chairs, his design looks a bit intimidating.
Most massage chairs rely on a combination of motors, gears, rollers and vibrating mechanisms. This kind of chair dates back more than half a century. Over the last few decades they’ve become much more sophisticated.
The simplest massage chairs use a series of vibrating surfaces to provide a massage. To create the vibrations, manufacturers use small devices that contain a weighted wheel or gear. The weight isn’t centered on the wheel, which makes the wheel unbalanced. When the device’s electric motor rotates the wheel rapidly, the rotation causes a vibration. Cell phones with a vibrating feature contain a small version of this kind of device. A massage chair needs several of these devices to generate vibrations across its surface without unbalancing the entire chair.
While no two massage chair manufacturers use the exact same design, there are some general design techniques that apply to most models. If you were to strip away the upholstery of the chair, you’d see a frame that supports a system of motors, gears and rollers.
When you’re getting a massage from a massage chair, it’s the rollers that act like a human’s hands. The rollers move in patterns determined by the structure of the frame. Some massage chairs rollers have a limited range of motion — they can only move up and down the back of the chair because they travel along a track attached to the frame. Electric motors provide the energy for the rollers.
Other massage chairs have more complexity. On these chairs, the manufacturer mounts the rollers onto a mechanical arm that can move laterally as well as vertically. This means the rollers can move left and right, or even in circles. Again, an electric motor powers the mechanical arm’s movements. A microprocessor in the massage chair stores recorded patterns the manufacturer pre-programs into the chair.
Many massage chairs allow the user to adjust the intensity of the massage. There are two main ways to adjust the intensity. One is to change how far the rollers move away from the frame when in massage mode. The second is to mount the frame on a pivot in the backrest, allowing it to move closer to or further away from the user’s back.
Since many massage chairs are recliners, manufacturers have to design electrical and mechanical systems that can operate in multiple positions. Some massage chairs have a motorized reclining system. The user can change the chair’s position by pressing a button on the massage chair’s control system. Other chairs require the user to pull a release handle before physically pushing back against the backrest of the chair.
Not all massage chairs rely on a purely mechanical approach. One design uses water, yet users stay completely dry. How does that work? Find out in the next section.
I KNEAD A MASSAGE
- Many massage chairs can perform a variety of massage techniques, such as:
- Kneading— the rollers move in a circular pattern
- Rolling— the rollers move up and down the backrest
- Tapping— the rollers alternate pushing in and out from the backrest, simulating the popular “karate chop” massage technique
- Gripping— the chair includes devices that grip user’s legs or arms in a snug hold before releasing
- Shiatsu— the rollers press against certain points on the user’s back (sometimes called acupoints) to relieve tension
One alternative to the purely mechanical approach is to use water. That’s the principle behind the design of the Hydro-Massage Chair invented by Frank J. Arzt. Arzt’s design allows the user to experience an invigorating massage using jets of water, yet remain perfectly dry.
His design includes a waterproof membrane similar to the kind found on a waterbed. The backrest for the chair contains the membrane. The front of the membrane — the side that is in contact with the user’s back — is restrained by a series of bars. Without the bars, the membrane becomes misshapen whenever the pressure of the water inside it changes. Valves at the top end of the membrane allows users or the manufacturer to fill the membrane cushion with water.
Along the back of the membrane are a series of nozzles. The nozzles connect by tubes to an electric pump, and a heating and cooling system. The pump re-circulates the water inside the chair, pushing it through the nozzles to create the massage sensation. The user sits back in the chair and receives a massage from the water jets. The heating and cooling system can adjust the water’s temperature to the user’s preference.
Arzt’s patent suggests that the nozzles could include a rotor inside the nozzle’s central passageway. The rotation of the rotor causes the water jet to rotate as well, increasing the area of impact on the user. By pulsing the water through the nozzles, the chair could simulate the tapping sensation you can get from some mechanical massage chairs.
Although Arzt filed his patent in 2000, the market hasn’t been flooded — pun intended — with hydro massage chairs. This could be due to the fact that massage chairs are still a small market for much of the world or perhaps the manufacturing process is too complex. But there are dry hydro-massage tables and mattresses on the market, so we may still see a chair variation in the future.
Some massage chairs use another technique that relies on air. How do massage chairs use air to relax an aching back? Keep reading to find out.
Arzt’s early hydro massage chair designs revealed a challenging problem. The water jets caused the waterproof membrane to distend and stretch in ways Arzt had not intended. The chair’s back would bulge out from the water pressure. To contain the membrane, Arzt added bars across the frame, making it look like a ladder. The bars held the membrane in place. But the membrane still bulged out near the top of the chair. No problem, claimed Arzt. It would wrap around the user’s neck and shoulders to provide a comfortable support for his or her head.