Linkage for lift/lowering control for a patient supporting platform

An elongate base for a patient supporting platform, comprising:

• a frame;
• first and second hydraulic jacks mounted at spaced apart locations on said frame adjacent opposite ends thereof, each of said first and second hydraulic jacks being configured to connect to said patient supporting platform for effecting a lifting and lowering of said patient supporting platform relative to said frame, said first and second hydraulic jacks each having a reciprocal input mechanism for effecting when reciprocated a lowering of said patient supporting platform, each said reciprocal input mechanism having a first part of a two part releasable connection thereon;
• a first manually operable member and a first mount for supporting said first manually operable member for reciprocal movement relative to said frame;
• a first linkage member having thereon a second part of said first two part releasable connection, said second part being releasably connected to said first part to effect a connecting of said first manually operable member to said reciprocal input mechanism on said first hydraulic jack, said first linkage including a releasable coupling mechanism interconnecting said first linkage member and said first manually operable member;
• a second manually operable member and a second mount for supporting said second manually operable member for reciprocal movement relative to said frame;
• a second linkage member having thereon a second part of said first two part releasable connection, said second part being releasably connected to said first part to effect a connecting of said second manually operable member to said reciprocal input mechanism on said second hydraulic jack, said second linkage member including a releasable coupling mechanism interconnecting said second linkage member and said second manually operable member.

An elongate base for a patient supporting platform, comprising:

• a frame;
• a manifold plate mounted on said frame;
• a hydraulic jack configured to connect to said patient supporting platform for effecting a lifting and lowering of said patient supporting platform relative to said frame, said manifold plate having connective passageways hydraulically connected to said hydraulic jack and a reciprocal input mechanism for effecting when reciprocated a lowering of said patient supporting platform, said reciprocal input mechanism comprising a plunger reciprocally movably supported in a hollow sleeve and having a region along a length thereof of reduced cross sections, at least one of said connective passageways being hydraulically connected to and extending between a hydraulic fluid reservoir for said hydraulic jack and said region;
• a valve member on said plunger oriented adjacent one end of said region and being reciprocally movable with said plunger, a valve seat on said hollow sleeve adjacent said one end of said region at least when said valve member and said valve seat engage one another;
• an elastically yieldable member for effecting continual urging of said valve member toward said valve seat;
• hydraulic fluid pressure equalizing means on said plunger and said hollow sleeve for assuring equalized fluid pressure acting on both ends of said region so that only a return force of said elastically yieldable member needs to be overcome in order to cause movement of said valve member away from said valve seat.

An elongate base for a patient supporting platform, comprising;

• a frame;
• first and second hydraulic jacks mounted at spaced apart locations on said frame adjacent opposite ends thereof, each of said first and second hydraulic jacks being configured to connect to said patient supporting platform for effecting a lifting and lowering of said patient supporting platform relative to said frame, said first and second hydraulic jacks each having a reciprocal input mechanism for effecting when reciprocated a lifting of the respective end of the patient supporting platform, each said reciprocal input mechanism having a first fastener part of a two part releasable fastener connection thereon, said two part releasable fastener connection being configured for a connected condition and an unconnected condition;
• a manually operable member and a mount for mounting said manually operable member for reciprocal movement relative to said frame;
• and
• a linkage member having thereon a pair of longitudinally spaced second fastener parts of each of said two part releasable fastener connections, said first and second fastener parts being configured to releasably connect to and disconnect from a respective other of said first and second fastener parts to effect a connecting of said manually operable member to each of said reciprocal input mechanisms, said first linkage being configured to convert the reciprocal movement of said manually operable member to a simultaneous reciprocal movement of said first linkage member and said reciprocal input mechanisms through a connected said first and second fastener parts to effect a simultaneous lifting of said patient supporting platform in response to the reciprocal movement of said manually operable member.