Vehicle seats
First Claim
1. A vehicle seat comprising a base part, a suspension including a gas spring, a seat part mounted on the suspension for upward and downward resilient movement relative to the base part, a source of compressed gas, valve means connecting the interior of the gas spring selectively to the source of compressed gas and to atmosphere, and electric circuit means including sensing means operative to sense any displacement of the seat part from a selected ride position, means operable in response to said sensing means for actuating the valve means to allow compressed gas to enter or leave the gas spring until the seat part has returned to its selected ride position, desensitizing means for inhibiting the electric circuit means from raising or lowering the seat part in response merely to vibrational movement of the seat part relative to the base part, an electric motor driven seat height control means operable to change the response of the sensing means and thereby cause the selected ride position to be raised or lowered, a coupling interconnecting the seat part and base part, two members of said coupling being relatively movable in response to upward or downward movement of the seat part relative to the base part thereby to change the response of the sensing means, and wherein said seat height control means is operable to vary the relative static position of said coupling members and thereby vary the response of the sensing means, said desensitizing means comprising time delay means operable to prevent activation of the valve means by said sensing means in response to any displacement of the seat part from the ride position which is maintained for less than a predetermined time period, and de-activation means arranged to render said time delay means inoperative during energisation of the said electric motor of the height control means.
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0 Petitions
Accused Products
Abstract
A vehicle seat has a seat part mounted on a base part by a suspension which includes a gas spring. Valve means are provided to control the seat ride position by controlling the entry and exit of compressed gas into and out of the gas spring. The difference between the actual ride position and a selected ride position of the seat is sensed, and a control circuit is used actuating the valve means to raise or lower the seat to reduce this difference to zero. In order to prevent seat vibration, such as is caused by passage of a vehicle over rough terrain, from continually causing actuation of the valve means, the control circuit is provided with desensitizing means.
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Citations
8 Claims
- 1. A vehicle seat comprising a base part, a suspension including a gas spring, a seat part mounted on the suspension for upward and downward resilient movement relative to the base part, a source of compressed gas, valve means connecting the interior of the gas spring selectively to the source of compressed gas and to atmosphere, and electric circuit means including sensing means operative to sense any displacement of the seat part from a selected ride position, means operable in response to said sensing means for actuating the valve means to allow compressed gas to enter or leave the gas spring until the seat part has returned to its selected ride position, desensitizing means for inhibiting the electric circuit means from raising or lowering the seat part in response merely to vibrational movement of the seat part relative to the base part, an electric motor driven seat height control means operable to change the response of the sensing means and thereby cause the selected ride position to be raised or lowered, a coupling interconnecting the seat part and base part, two members of said coupling being relatively movable in response to upward or downward movement of the seat part relative to the base part thereby to change the response of the sensing means, and wherein said seat height control means is operable to vary the relative static position of said coupling members and thereby vary the response of the sensing means, said desensitizing means comprising time delay means operable to prevent activation of the valve means by said sensing means in response to any displacement of the seat part from the ride position which is maintained for less than a predetermined time period, and de-activation means arranged to render said time delay means inoperative during energisation of the said electric motor of the height control means.
- 6. A vehicle seat comprising a base part, a seat part, a suspension mounting the seat part on the base part for upward and downward resilient movement relative thereto, said suspension including a gas spring, a source of compressed gas, valve means connecting the interior of the gas spring selectively to a source of compressed gas and to atmosphere, and electric circuit means including sensing means arranged to sense displacement of the seat part from a selected ride position and to output a corresponding signal, means arranged to receive said signal and to actuate the valve means in response thereto to allow compressed gas to enter or leave the gas spring until the seat has returned to its selected ride position, averaging means arranged normally to average said signal prior to receipt by the valve-actuating means to reduce the possibility of the valve-actuating means causing raising or lowering of the seat part in response merely to vibrational movement of the seat part relative to the base part, said averaging means being de-activatable to enable the valve-actuating means to be directly responsive to said signal under pre-determined operational conditions of the seat, adjustment means operable to change said selected ride position, said averaging means comprising a delay circuit path and a no-delay circuit path in parallel and both arranged to receive said signal from the sensing means, the delay circuit path being operative to average said signal in passage therealong, and control means normally inhibiting said no-delay circuit path while enabling the delay circuit path, the control means being operative in response to energisation of said adjustment means to inhibit said delay circuit path and enable the no-delay circuit path.
Specification