HYDRAULIC ADJUSTING APPARATUS FOR HOSPITAL BEDS OR THE LIKE

• US 3,724,003 A
• Filed: 01/03/1972
• Issued: 04/03/1973
• Est. Priority Date: 07/08/1971
• Status: Expired due to Term

• Current Assignee: August Kraisel, Hans Ellwanger, Walter Kraus, Wilheim Zirps
• Original Assignee: August Kraisel, Hans Ellwanger, Walter Kraus, Wilheim Zirps
• Inventors: Ellwanger, Hans, Kraisel, August, Kraus, Walter, Zirps, Wilheim
• Primary Examiner(s): Nunberg, Casmir A.
• Application Number:
  US05/214,949
• Time in Patent Office: 456 Days
• Field of Search: 5/63,66-69 60/97P,DIG.2 91/412,459
• US Class Current: 5/614
• CPC Class Codes: A61G 7/002 having adjustable mattress frame
• CPC Class Codes: A61G 7/018 Control or drive mechanisms
• CPC Class Codes: Y10S 60/911 Fluid motor system incorporating electrical system

Abstract

The head and foot ends of a mattress supporting frame or operating table are articulately connected with the piston rods of two hydraulic motors whose double-acting cylinders are articulately connected to a shiftable bottom frame. The lower chambers of the cylinders can be connected with a supply conduit for pressurized fluid by way of discrete working conduits and discrete solenoid operated directional control valves. The upper chambers of the two cylinders are connected to each other by a first control conduit and the first control conduit is connected with the working conduit for the cylinder at the head end by means of a second control conduit. The supply conduit receives pressurized fluid from a single pump and each valve is further connected with a return conduit for spent fluid. The valve members of the two valves are movable independently of each other between first or neutral positions in which they seal the supply conduit and the return conduit from the respective working conduits, second positions in which they connect the supply conduit with the respective working conduits, and third positions in which they connect the return conduit with the respective working conduits. A solenoid operated shutoff valve can be installed in the working conduit for the cylinder at the head end to seal the lower chamber of such cylinder from the supply and return conduits as well as from the respective working conduit and both control conduits when the foot end is to be raised or lowered without any changes in the level of the head end. The single pump can supply pressurized fluid to the motors for one or more additional frames or tables as well as to auxiliary cylinders which can move the head rest and/or the foot rest of a frame or table between different levels and/or different positions of inclination.

Claims

1. In a structure of the character indicated, particularly in a hospital bed, a combination comprising an adjustable component having spaced first and second portions;

and an adjusting apparatus for moving said portions of said component together with and relative to each other, said apparatus including a source of pressurized hydraulic fluid, a pair of hydraulic motors, one for each of said portions, each of said motors comprising a double-acting cylinder member, a piston reciprocable in and dividing the interior of said cylinder member into first and second chambers, and a piston rod connected with said piston and extending through and beyond said second chamber, one of said members being connected with the respective portion of said component, supply conduit means connected with said source, a pair of working conduits each connected with a different one of said first chambers, control conduit means connecting said second chambers with each other and with one of said working conduits, a pair of directional control valves each connected with said supply conduit means and with a different one of said working conduits, and fluid evacuating conduit means connected with said valves, each of said valves having a portion movable between a plurality of positions including a first position in which the respective working conduit is sealed from said supply conduit means and from said evacuating conduit means, a second position in which the respective working conduit is connected with said supply conduit means, and a third position in which the respective working conduit is connected with said evacuating conduit means.

2. A combination as defined in claim 1, wherein said component is the mattress supporting frame of a hospital bed and said first and second portions respectively constitute the head and foot ends of said frame.

3. A combination as defined in claim 2, wherein said one member is said piston rod member and said valves are solenoid-operated directional control valves.

4. A combination as defined in claim 3, wherein said one working conduit is connected with the first chamber of the cylinder member of the motor for said head end of said frame.

5. A combination as defined in claim 1, further comprising third valve means provided in said one working conduit intermediate the respective first chamber and the connection of said one working conduit with said control conduit means, said third valve means having a portion movable between first and second positions in which said third valve means respectively permits and prevents the flow of fluid between said last mentioned first chamber and said control conduit means.

6. A combination as defined in claim 5, wherein said third valve means is a solenoid-operated valve.

7. A combination as defined in claim 5, wherein said third valve means is a shutoff valve and said portion of said third valve means normally dwells in said second position.

8. A combination as defined in claim 1, further comprising at least one second component and additional adjusting apparatus for said second component, said supply conDuit means and said evacuating conduit means forming part of said additional adjusting apparatus.

9. A combination as defined in claim 1, further comprising an auxiliary component movable relative to said first mentioned component, said adjusting apparatus further comprising a third motor for moving said auxiliary component and directional control valve means interposed between said third motor and said supply and evacuating conduit means.

10. A combination as defined in claim 9, wherein said first mentioned component is the mattress supporting frame of a hospital bed and said first and second portions respectively constitute the head and foot ends of said frame, said auxiliary component constituting a head rest which is pivotably connected with said frame in the region of said head end.

11. A combination as defined in claim 9, wherein said first mentioned component is the mattress supporting frame of a hospital bed and said first and second portions respectively constitute the head and foot ends of said frame, said auxiliary component constituting a foot rest articulately connected with said frame in the region of said foot end.

12. A combination as defined in claim 1, wherein said source comprises a pump and electric motor means for driving said pump in response to movement of at least one of said portions of said valves from the respective first position.

13. A combination as defined in claim 1, further comprising a base articulately connected with the other member of each of said motors.

14. A combination as defined in claim 1, wherein each of said pistons has a relatively large end face adjacent to the respective first chamber and a relatively small second end face adjacent to the respective second chamber.

15. A combination as defined in claim 1, wherein said cylinders are mounted in at least substantially upright positions and said first chambers are located below the respective second chambers.