Hospital bed
First Claim
1. A hospital bed adjustable in height and selectively movable to Trendelenburg and reverse Trendelenburg positions at any height comprising:
- a base having first and second ends;
a bed support frame having first and second ends;
first and second actuators; and
first and second mechanical drives connected between said first and second ends of said base and said bed support frame, respectively, each of said mechanical drives being connected to one of said actuators whereby selectively operating said actuators to move said ends of said bed support frame in the same direction changes the height of said bed support frame relative to said base, and selectively operating said actuators to move said first and second ends of said bed support frame vertically relative to one another moves said bed support frame to the Trendelenburg and reverse Trendelenburg positions;
each of said first and second mechanical drives comprising a lift arm link having first and second ends, said first end being pivotally connected to one end of said base and said second end being operably pivotally connected to a drive mechanism, said lift arm link being pivotally connected intermediate its ends to said bed support frame;
said drive mechanism having a drive screw connected to ne of said actuators and having an output block operably connected to said drive screw and said second end of said lift arm link whereby said output block translates in response to said actuator rotating said drive screw;
each of said drive mechanisms further comprising;
a lift nut mateably threaded with said drive screw, said lift nut being operable to translate along said drive screw in response to rotation of said drive screw; and
said output block is slidably mounted on said lift nut whereby operation of said actuator in first and second rotational directions translates both said lift nut and output block in respective first and second directions thereby lowering and raising one end of said bed support frame respectively.
2 Assignments
0 Petitions
Accused Products
Abstract
A hospital bed has two mechanical drive mechanisms connected between each end of a bed support frame and a base, each of which has a respective actuator. Selective operation of each of the drive mechanisms with the actuators permits either end of the bed support frame to be inclined to the Trendelenburg and reverse Trendelenburg positions at any height of the hospital bed. The drive mechanisms transfer forces for raising and lowering the bed support frame but do not transfer force when the bed is lowered onto an obstacle. When an obstacle is encountered, a switch interrupts operation of its respective actuator.
171 Citations
12 Claims
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1. A hospital bed adjustable in height and selectively movable to Trendelenburg and reverse Trendelenburg positions at any height comprising:
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a base having first and second ends; a bed support frame having first and second ends; first and second actuators; and first and second mechanical drives connected between said first and second ends of said base and said bed support frame, respectively, each of said mechanical drives being connected to one of said actuators whereby selectively operating said actuators to move said ends of said bed support frame in the same direction changes the height of said bed support frame relative to said base, and selectively operating said actuators to move said first and second ends of said bed support frame vertically relative to one another moves said bed support frame to the Trendelenburg and reverse Trendelenburg positions; each of said first and second mechanical drives comprising a lift arm link having first and second ends, said first end being pivotally connected to one end of said base and said second end being operably pivotally connected to a drive mechanism, said lift arm link being pivotally connected intermediate its ends to said bed support frame; said drive mechanism having a drive screw connected to ne of said actuators and having an output block operably connected to said drive screw and said second end of said lift arm link whereby said output block translates in response to said actuator rotating said drive screw; each of said drive mechanisms further comprising; a lift nut mateably threaded with said drive screw, said lift nut being operable to translate along said drive screw in response to rotation of said drive screw; and said output block is slidably mounted on said lift nut whereby operation of said actuator in first and second rotational directions translates both said lift nut and output block in respective first and second directions thereby lowering and raising one end of said bed support frame respectively. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A mechanical drive adapted to be connected to an actuator for moving a load on a bed support frame relative to a base, said load exerting a gravitational force on said mechanical drive, said mechanical drive comprising:
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a drive screw adapted to be connected to the actuator; a lift nut rotatably mounted to said drive screw, said lift nut being operable to translate along said drive screw in response to rotation of said drive screw; an output block slidably mounted on said lift nut whereby operation of the actuator in first and second rotational directions translates both said lift nut and output block in respective first and second directions thereby moving the load in correspondingly different directions; and
,a linkage having one end pivotally connected to said output block and another end pivotally connected to said base, said linkage pivotally connected to the load at a point intermediate its ends and being operable to apply the gravitational force of the load to said output block to bias said output block against said lift nut. - View Dependent Claims (9, 10, 11)
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12. A hospital bed comprising:
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a base having first and second ends; a bed support frame having first and second ends; first and second actuators mounted on said bed support frame; and first and second mechanical drives, each of said mechanical drives operatively connected between one of said actuators and said base and including; a drive screw connected to one of said actuators, a lift nut rotatably mounted on said drive screw, said lift nut translating along said drive screw in response to rotation of said drive screw, an output block slidably mounted on said lift nut whereby rotation of said actuator in first and second directions translates both said lift nut and said output block in respective first and second directions thereby generally raising and lowering one end of said bed support frame, a linkage having one end pivotally connected to said output block and another end pivotally connected to said base, and a switch connected to said drive mechanism for detecting a relative motion between said lift nut and said output block in response to an obstacle obstructing said one end of said bed support frame from lowering, said switch being operable upon activation of said switch to interrupt operation of an actuator lowering said one end of said bed support frame.
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Specification