Patent Application
20100109407
The present invention relates generally to chairs for supporting a patient during examinations and treatments, and more particularly to a chair for use in a dental operatory.
Conventional dental operatories generally include an articulating dental chair for supporting a patient in a variety of positions to facilitate the performance of dental procedures and operations. For example, dental chairs are generally adapted to be raised and lowered relative to a floor surface, and to be moved between a first orientation/position where a seatback is upright or inclined relative to a seat base to support the patient in a seated position, and a second orientation/position where the seatback is reclined to support the patient in a generally supine position.
In some dental chairs, the seat cushion is supported by a chair frame and the back cushion is coupled to an upright support that moves relative to the chair frame along a predetermined path or track (i.e., the support does more than merely pivot with respect to the chair frame). This upright support is sometimes referred to as a “carriage.” A lower portion of the carriage is typically received between sidewalls of the chair frame. The carriage slides relative to the chair frame between the sidewalls and along the predetermined path to move the dental chair between the first and second orientations mentioned above.
Typically, once the first or second orientation/position is requested by a user, the motions associated with that orientation are performed until completion of the orientation. Often times, however, there may be an obstruction below the seatback that may interfere with the reclining seatback in the second orientation/position. The seatback is typically very heavy as it is meant to support a patient, and may cause pain or discomfort to the obstruction if the obstruction is another person. Despite the obstruction, the seatback typically continues to try to recline, causing additional pain or discomfort.
As an example, a dental hygienist may be sitting with his or her legs below the seatback, get distracted (e.g., assisting the dentist, preparing for the procedures, reviewing the charts, etc.), and not notice that the seatback is reclining until contact with the seatback. Upon contact by the seatback with the hygienist's legs, the seatback typically tries to continue to recline despite the dental hygienist's legs, often causing pain or discomfort. As such, the hygienist may be pinned down by the heavy seatback.
Thus, a need therefore exists in the art for a safer manner of reclining the seatback of the dental chair.
The invention addresses these and other problems associated with the prior art by providing dental devices with cylinders, trunnions, and limit switches. The dental devices may be dental chairs. When the limit switch of the dental device is actuated, downward movement of the seat back may be stopped, often limiting further pain or discomfort to a user.
In some embodiments, the dental device may comprise a cylinder and a trunnion having a cavity and an outer surface. A portion of the cylinder is slidably mounted within the cavity of the trunnion and a portion of the cylinder protrudes out of the trunnion. The device may also include a limit switch coupled to the outer surface of the trunnion, where the limit switch contacts the cylinder. Separation of the limit switch and the cylinder causes actuation of the limit switch. The actuation of the limit switch stops a downward movement of the device. In other embodiments, the limit switch is coupled to the portion of the cylinder that protrudes out of the trunnion, and the limit switch contacts the trunnion. Separation of the limit switch and the trunnion, in these embodiments, causes actuation of the limit switch, stopping the downward movement of the device.
The invention also addresses problems associated with the prior art by providing a method of operating the dental device. The method includes providing a limit switch for the device that controls a downward movement of the device and initiating the movement of the device. The movement includes use of a cylinder and a trunnion. The method may also include detecting an obstruction, and in response to the detected obstruction, actuating the limit switch to stop the movement of the device.
These and other advantages and features, which characterize the invention, are set forth in the claims annexed hereto and forming a further part hereof. However, for a better understanding of the invention, and of the advantages and objectives attained through its use, reference should be made to the Drawings, and to the accompanying descriptive matter, in which there are described exemplary embodiments of the invention.
Turning to the drawings, wherein like numbers denote like parts throughout the several views,
The chair 2 generally comprises a base 4, a lift arm 6 extending upwardly from base 4, and a seat assembly 8 supported by lift arm 6. The lift arm 6 raises and lowers the seat assembly 8 relative to the base 4. Lowering and raising the lift arm 6 is generally disclosed in U.S. patent application Ser. No. ______, filed on even date herewith by ______ et al. and entitled “DENTAL CHAIR WITH CANTILEVER FORWARD BASE” (MIDTF 467P2), the entire disclosure of which is incorporated by reference herein.
A seatback support 10 (referred to as a “carriage”) extends generally upwardly from the seat assembly 8 for supporting a seatback frame 12 and a back cushion 14 mounted to the seatback frame 12. The seat assembly 8 includes a chair frame 20 pivotally mounted on a base structure 5, which is attached to the lift arm 6, a casing 22 mounted to the chair frame 20, and a seat cushion 24 positioned over the chair frame 20 and the casing 22. The seatback frame 12 may move downwardly by the downward movement of the seatback support 10 relative to the chair frame 20. The seatback frame 12 may move upwardly by the upward movement of the seatback support 10 relative to the chair frame 20. Indeed, the seatback frame 12 of the chair 2 can move from the generally upright orientation/position shown in
It is worth noting that movement of the seatback frame 12 may be independent from movement of the lift arm 6, and vice versa. For example, the seatback frame 12 may be moved downwardly to a generally reclined position without raising or lowering the lift arm 6. Indeed, the two separate motions may be performed consecutively or may be performed at about the same time. Moreover, the chair 2 may be preprogrammed using conventional techniques to achieve a certain setting, which may include movement of the seatback frame 12 alone, movement of the lift arm 6, alone, or movement of both the seatback frame 12 and the lift arm 6. Movement by both to accomplish the preprogrammed setting may be performed consecutively or at about the same time.
The chair 2 may have an input member (not shown) for moving the seatback frame 12 downwardly, a separate input member (not shown) for moving the seatback frame 12 upwardly, a separate input member (not shown) for lowering the lift arm 6, a separate input member (not shown) for raising the lift arm 6, and/or a separate input member (not shown) for a certain preprogrammed setting. The input member may be a button that may be depressed, a foot pedal that may be depressed, etc. Alternatively, the input member need not be depressed and may simply require contact. The user may select any of these positions by depressing the foot pedal (not shown), for example, until the desired position is achieved. However, when a setting is preprogrammed, the user may simply depress, for example, the preprogrammed input member to initiate the movement of the preprogrammed setting. The movement may occur without further action by the user, and the user may even be able to walk away from the chair 2 to tend to another matter.
Thus, the transition of the chair 2 to the manner shown in
To move the seatback frame 12, the chair frame 20 supports a drive mechanism 26 between first sidewall 28 and second sidewall 30 (
To support this arcuate motion, the chair 2 may also contain a hydraulic fluid reservoir 41 and control circuitry 42, both in the lift arm 6. The control circuitry 42 may be in the form of a printed circuit board (PCB). The chair 2 may also include a solenoid 43, which is associated with the drive mechanism 26 for the downward movement of the seatback frame 12. Solenoid 43 opens or closes a valve 44, with hydraulic fluid passing through the valve 44 when the valve 44 is opened. The chair 2 may additionally include a solenoid 45, which is associated with the drive mechanism 26 for the upward movement of the seatback frame 12. The solenoid 45 may also open or close the valve 44. Indeed, the valve 44 may be placed between the solenoids 43 and 45. Each of the solenoids 43, 45 may be configured to normally keep the valve 44 closed unless an electronic signal is sent to either of the solenoids 43, 45 to open the valve 44.
Additional solenoids and valves (not shown) may be utilized for the downward movement of the lift arm 6 to lower the lift arm 6. Similarly, separate solenoids and valves (not shown) may be utilized for the upward movement of the lift arm 6 to raise the lift arm 6. Nonetheless, all of the solenoids and valves, including the solenoids 43, 45 and the valve 44, may be within a manifold (not shown) in base 4. A pump 47 may be present as illustrated in
Turning to
The drive mechanism 26 may include a one-way hydraulic cylinder 68 positioned within a cavity of a housing such as within a cavity of a trunnion 70. A portion of the cylinder 68, such as that closest to seatback support 10, may protrude out of the trunnion 70. The portion of the cylinder 68 that protrudes out of trunnion 70 may have an outside diameter of about 2¼ inches and an inside diameter of about 1¾ inches. The portion of the cylinder 68 within the cavity of the trunnion 70, and that does not protrude, may have an inside diameter of about 1½ inches. The trunnion 70 may have an outside diameter of about 2¼ inches. The trunnion 70 may also be pivotally mounted to the chair frame 20. Pivot axis 71 illustrates the general pivot point of the trunnion 70.
Returning to
As the force of drive mechanism 26 is released by the exiting hydraulic fluid, one or more return springs 76 (
Once the reclined position is achieved, the control circuitry 42 stops signaling the solenoid 43, and the solenoid 43 closes the valve 44. When a reclined position is achieved by the seatback frame 12 may depend upon, for example, a preprogrammed setting, the length of time the request is held for by a user, etc. Nonetheless, additional hydraulic fluid may be prevented from exiting the cylinder 68 when the valve 44 is closed, and the reclined position may be maintained until a request for the generally upright position is received.
When a user requests that the seatback frame 12 transition into an upright position (e.g., with the user still sitting in the chair 2), the request may cause a signal to be sent to the control circuitry, which in turn, may cause the control circuitry 42 to send a signal to the solenoid 45 to open the valve 44. The control circuitry 42 may utilize transistor circuits to send electrical current to the solenoid 45, which moves a spool to open the valve 44. As such, the hydraulic fluid may flow from the hydraulic fluid reservoir 41 to the manifold (not shown) containing the solenoid 45, then through the opened valve 44, up into back hose 72, and into the cylinder 68. As the hydraulic fluid may be under pressure, the pressure may cause the fluid to flow upwards into the back hose 72. The front hose 73 may again serve as a catchall hose to transport seeping hydraulic fluid into the hydraulic fluid reservoir 41.
As the hydraulic fluid enters the cylinder 68, the hydraulic fluid acts on the cylinder rod 38, which in turn applies a pushing force to move the lower portion 34 of the seatback support 10 toward a rearward end 79 of each arcuate track 40. The first, second, and third guide shafts 46, 54, 56 (
Next, the chair 2 may further include a locking assembly 80 (
Turning to the view of the limit switch 82 in
A restraint member such as a fastener 86 (such as a pin, a screw, etc.) may be coupled to the trunnion 70 and operable to engage the bracket 84 (e.g., by passing through the bracket 84). The fastener 86 may reduce or inhibit rotational movement of the cylinder 68 within the trunnion 70. The fastener 86 may be a low pressure fitting, and may also reduce or prevent interference with other components (e.g., interference of the front hose 73 on the cylinder 68 with the springs 76 in
The limit switch 82 may start off in a contacting state, as illustrated in
Turning to
The obstruction may be an operator or a portion of the operator such as the legs of the operator. Alternatively, the obstruction may be an inanimate object such as the box 92 (
Turning to
Indeed, actuation of the limit switch 82 may stop the flow of electric current to the solenoid 43. For example, there may be an interlock in control circuitry 42 between the limit switch 82 and the solenoid 43 such that they are wired together, with the electric current flowing from the limit switch 82 to the solenoid 43. Actuation of the limit switch 82 may break the electric current and cut power to the solenoid 43, which closes the valve 44.
Those of ordinary skill in the art will appreciate that by stopping the downward movement of the seatback frame 12 against the box 92, further damage to the box 92 may be reduced. Furthermore, when the obstruction is an operator or portion of the operator, stopping the downward movement may limit further pain or discomfort to the operator.
The transition of the limit switch 82 from the contacting state to the non-contacting state is illustrated in further detail in
By
It is worth noting that the limit switch 82 may be actuated more often when the user utilizes a preprogrammed setting because in such an instance, the user may walk way from the chair 2 as he or she may not need to keep an input member depressed for the movement to occur.
In some embodiments, program code may be implemented to prevent (e.g., temporarily prevent) initiation of a downward movement in response to actuation of the limit switch 82. As such, a user, for example, may not be able to lower the seatback frame 12 any further if he or she accidentally clicks on the input member (not shown) to move the seatback frame 12 downwards instead of the input member to move the seatback frame 12 upwards. Furthermore, in some embodiments, program code may be implemented to automatically initiate another movement. For example, an upward movement of the seatback frame 12 may be initiated via the program code upon actuation of the limit switch 82 to ease a user's pain or discomfort.
In general, the program code may include the routines executed to implement or initiate movements of the chair 2, whether the program code is implemented as part of an operating system or a specific application, component, program, object, module or sequence of instructions, or even a subset thereof, will be referred to herein as “computer program code,” or simply “program code.” Program code typically comprises one or more instructions that are resident at various times in various memory and storage devices in a computer, and that, when read and executed by one or more processors in the computer such as with control circuitry 42 (
Given the typically endless number of manners in which computer programs may be organized into routines, procedures, methods, modules, objects, and the like, as well as the various manners in which program functionality may be allocated among various software layers that are resident within a typical computer (e.g., operating systems, libraries, API's, applications, applets, etc.), it should be appreciated that the invention is not limited to the specific organization and allocation of program functionality described herein.
With reference to
Next, in some embodiments, the chair 2 may include at least one at electric field sensor (not shown) having capacitive sensing in the seatback frame 12. The sensor may be operable to detect a change in capacitance created by contact with an obstruction that is a user and actuate the limit switch 82. The sensor (not shown) may function cooperatively with the limit switch 82, and may additionally actuate the limit switch 82. A single sensor may cover, for example, the entire seatback frame 12. Alternatively, multiple sensors may cover separate portions of the seatback frame 12. More information about electric field sensors may be found in U.S. patent application Ser. No. ______, filed on even date herewith by ______ et al. and entitled “DEVICE WITH AN ELECTRIC FIELD SENSOR, CONTROL CIRCUITRY, AND A SOLENOID” (MIDTF 472P2), the entire disclosure of which is incorporated by reference herein.
While exemplary embodiments have been described in considerable detail herein, it is not the intention of the application to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. For example, with reference to
Alternatively, as the outer diameter of the trunnion 70 and the outer diameter of the protruding portion of the cylinder 68 may be the same, the limit switch 82 may simply be placed in between the trunnion 70 and the cylinder 68, on either the trunnion 70 or the cylinder 68. Moreover, with respect to the trunnion 70, the limit switch 82 may be generally placed on the vertical outer surface (e.g., directly on the vertical outer surface or indirectly on the vertical outer surface) closest to the protruding portion of the cylinder 68, instead generally placed on the horizontal outer surface 81 that the limit switch 82 is placed on in
Additionally, with reference to
Therefore, the invention in its broader aspects is not limited to the specific details or representative devices and method, and illustrative examples shown and described. Accordingly, departures may be made form such details without departure from the spirit or scope of applicant's general inventive concept.
U.S. patent application Ser. No. ______, filed on even date herewith by ______ et al. and entitled “DENTAL CHAIR WITH CANTILEVER FORWARD BASE” (MIDTF 467P2), the entire disclosure of which is incorporated by reference herein. U.S. patent application Ser. No. ______, filed on even date herewith by ______ et al. and entitled “PATIENT CHAIR WITH LOCKING ASSEMBLY” (MIDTF 469P2), the entire disclosure of which is incorporated by reference herein. U.S. patent application Ser. No. ______, filed on even date herewith by ______ et al. and entitled “DEVICE WITH AN ELECTRIC FIELD SENSOR, CONTROL CIRCUITRY, AND A SOLENOID” (MIDTF 472P2), the entire disclosure of which is incorporated by reference herein.
