JP2007014492A - Hold detection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a simply- and economically-structured, safe medical apparatus which comprises means to observe a pushing bar holding status and to communicate a signal in line with the holding status to a control circuit with high reliability during a solution sending action in which the pushing bar pushes out a solution contained in a container having a solution sending section at its one end through the other end according to a control by the control circuit built in the apparatus. <P>SOLUTION: The hold detection apparatus for a pushing bar is simple and economical, in which an indication signal is generated magnetically according to the fact whether or not the pushing bar is held by a hold structure for holding the pushing bar and an indication signal communication means to communicate the generated indication signal to the control circuit wirelessly is included. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an improvement of a syringe pusher detection device mounted on a medical device such as a push-out type liquid feeding device or a hemodialysis device that feeds liquid stored in a container in advance with a pusher.

  In general, in a mechanism that pushes liquid stored in a container out of the container with a pusher that moves along the inner cylinder of the container, the pusher is moved while being pressed against the collar provided at the end of the pusher. A method of extruding the applied liquid is adopted. In this case, the container containing the liquid is provided with a liquid feeding section having a small-diameter hole for liquid feeding on the side opposite to the surface pressed by the pusher. In many cases, a tube constituting a liquid supply path is connected to the liquid supply unit, and liquid can be supplied to a desired place by the pressing operation of the pusher. This pressing against the pusher may be manually pushed in if liquid feeding control does not require accuracy, but if the liquid feeding is performed at a constant speed for a long time, it is performed using a mechanical device. .

  As an example of liquid feeding using such a mechanical device, there is a conventional example disclosed in Patent Document 1. This example shows a syringe pump device used for injection of an anticoagulant heparin that prevents blood coagulation in the extracorporeal circuit of the hemodialysis apparatus. In FIG. 2 of Patent Document 1, the flange 19 of the plunger 18 (presser) of the syringe 6 is engaged with the groove 21 provided in the movable arm 20 (holder), and the rack bar 22 and the pinion 23 of the motor 3 are engaged. Thus, the movable arm 20 is moved linearly, and as a result, the operation of pushing out the anticoagulant in the syringe 6 with the plunger 18 is executed.

However, like the hemodialysis machine shown in this conventional example, when a medical solution is automatically injected into a patient for a long time, if the syringe pusher is removed from the holder holding mechanism for some reason, In such a syringe pump device, it is indispensable to add a function that can always monitor the gripping state of the pusher. However, Patent Document 1 discloses a specific disclosure regarding the function. Not done.
Japanese Utility Model Publication No. 6-13743

  The problem to be solved is that the pusher gripping state is always maintained during the liquid feeding operation in which the liquid contained in the container having the liquid feeding part at one end is pushed out by the pusher from the other end side according to the control by the control circuit incorporated in the apparatus. There is no means for monitoring and transmitting the grip state signal to the control circuit with high reliability, and a safe medical device cannot be realized with a simple and inexpensive configuration.

  The present invention provides a sign signal transmission means for magnetically generating a sign signal according to whether or not the pusher is gripped by a gripping mechanism for gripping the pusher and transmitting the generated sign signal to the control circuit wirelessly. In particular, the sign signal transmission means includes a magnetic plate extending opposite to the moving direction of the gripping mechanism and a magnetosensitive element on the opposite surface, and the pusher is moved toward the magnetic plate. The main feature is that a magnet is provided that comes close to and away from each other depending on whether or not it is gripped, and that the state of proximity and separation of the magnet can be converted into an electrical signal by the magnetosensitive element.

  In the gripping detection device of the present invention, since the sign signal generated magnetically according to the gripping state of the pusher is reliably transmitted to the control circuit wirelessly, if the pusher is detached from the gripping mechanism for some reason, Because it is possible to stop the medical action in the device and issue an alarm to the administrator such as a doctor or nurse, a safe medical device equipped with a pusher grip detection device with a simple and inexpensive configuration There is an advantage that can be provided.

  Realizing a safe medical device by reliably detecting the gripping state of the pusher, that is, the problem of detachment of the pusher while the liquid stored in the container having the liquid feeding part at one end is pushed out from the other end by the pusher This was achieved with a simple and inexpensive configuration without compromising the liquid feeding function of the pusher.

  FIG. 1 is a schematic view of an embodiment of the apparatus of the present invention, in which 1 is a liquid feeding device, 2 is a container containing a liquid, 3 is a container flange, 5 is a pusher, and 6 is a pressing surface of the pusher. Consists of parts, 7 is a holder, 8A and 8B are hook-like hooks, 9A and 9B are pivoting fulcrums of hook-like hooks 8A and 8B, 10 is a spring of elastic biasing means for hook-like hooks 8A and 8B, 11 The release button, 13 is a pusher gripping detection chip, 102 is a detection lever, 104 is a magnet, 105 is installed on the liquid feeding device 1 side, and the magnetic plate 106 combined so as to face each other is provided between the facing magnetic plates 105 Magnetosensitive element, 14 is a guide rod coupled to the holder 7, 17 is a drive motor, 20 is a lead screw, 21 is a nut that engages with the lead screw 20, and the guide rod 14 is moved according to the rotation of the lead screw 20. That the carriage, the linear encoder for detecting the moving position of the carriage 21 23, 24 is a clamp for closing the liquid supply path 25 in response to a command.

  In the figure, the power of the drive motor 17 attached to the support frame 16 is transmitted to the lead screw 20 via the driven gear 19 that meshes with the pinion gear 18 at one end of the pinion gear 18 and the lead screw 20 to rotate the lead screw 20. The carriage 21 containing a nut (not shown) that meshes with the lead screw 20 is linearly moved in accordance with this rotation. The carriage 21 is provided with an optical sensor 22, and the current position of the carriage 22 can be grasped from the slit signal of the linear encoder 23 arranged so as to face the optical sensor 22. The guide bar 14 and the holder 7 are integrally coupled to the carriage 21. When the carriage 21 linearly moves in the arrow S direction, the holder 7 also linearly moves in the arrow S direction at the same time. The carriage 21 also includes a clutch mechanism that can release the engagement between the nut and the lead screw 20 contained therein. When the release button 11 is pressed, the clutch mechanism is activated and the nut and lead screw contained in the carriage 21 are engaged. The 20 meshing is released, and the holder 7 can be moved manually. The drive motor 17 is generally a stepping motor or a DC motor. In addition to an optical type as the linear encoder 23, an optical or magnetic rotary encoder is provided at the other end of the lead screw 20 as an alternative to the linear encoder 23. The same function can be realized even if installed. A similar function can be realized even if such a drive mechanism is composed of a linear motor and a linear encoder.

  The holder 7 has a pusher gripping detection chip 13 which faces the pressing surface of the collar 6 and can move linearly, and a dogleg shape which moves around the fulcrum 101 by pressing the pusher gripping detection chip 13 on the tip. A lever 102 is prepared. One end of the detection lever 102 is urged by a tension spring 103 in a direction in which the detection lever 102 comes into contact with the pusher grip detection chip 13, and a magnet 104 is provided on the other end side. For this reason, the detection lever 102 is rotated by pushing the pusher gripping detection chip 13, and as a result, the magnet 104 is also moved in the direction of arrow R in the figure. Further, in the liquid feeding device 1, a magnetic plate 105 combined so as to face along the moving direction of the holder 7 is extended, and a magnetosensitive element 106 is provided between the facing magnetic plates 105. Therefore, when the facing magnetic plate 105 is short-circuited with a magnet, a magnetic flux passes through the magnetic sensing element 106 and an active signal is output from the magnetic sensing element 106.

  FIG. 2 is a view of FIG. 1 as viewed from the direction of arrow V, and shows the positional relationship among the magnet 104, the magnetic plate 105, and the magnetosensitive element 106 as described above. As an example, the magnet 104 provided at one end of the detection lever 102 is magnetized like the (N) pole and (S) pole in the figure, and when the magnet 104 is close to the magnetic plates 105A and 105B, the magnetic flux generated by the magnet is generated. Flows from the magnetic plate 105 </ b> A to the magnetic plate 105 </ b> B. As a result, the magnetic flux passes through the magnetosensitive element 106, and an active signal appears at the output terminal 107. Accordingly, when the push-in state of the pusher grip detection chip 13 changes in accordance with the grip state of the pusher 5 and the detection lever 102 also rotates and the magnet 104 approaches or separates from the magnetic plate 105, the presence or absence of the pusher grip is determined. A sign signal transmitting means for generating a sign signal indicating the state of the mark and wirelessly transmitting the sign signal from the holder 7 side to the control circuit in the liquid delivery apparatus 1 is configured.

  A packing 4 that is in close contact with the inner wall of the container 2 is provided on the liquid contact surface side of the pusher 5 inserted into the container 2. When the flange 6 of the pusher 5 is pushed in while supporting the flange 3, the container 2 The liquid stored in the container 2 is fed from the liquid feeding path 25 connected to the liquid feeding section 26. Clamps 24A and 24B are provided in the middle of the liquid supply path 25, and the linear motion pins 27A and 27B incorporated therein are arranged to face each other so as to close the liquid supply path 25 in response to a command signal. . It is obvious that the same purpose can be achieved with one clamp using either the clamp 24A or the clamp 24B as a simple wall.

  FIG. 3 shows a state in which the clamps 24A and 24B are activated and the liquid supply path 25 is closed by the linear motion pins 27A and 27B. When the pusher 5 is pushed in this state, the liquid pressure inside the container 2 increases, but the liquid in the container 2 does not flow beyond the closed position of the liquid feeding path 25. FIGS. 4A, 4B, and 4C show a process of gripping the collar portion 6 of the pusher 5 in the closed state shown in FIG. When the drive motor 17 is rotated according to the operation start command of the liquid delivery device 1, the holder 7 is moved in the direction of arrow M as shown in FIG. At this time, the slanting contact surface formed at the front end portion of the hook-like hooks 8A and 8B biased in the closing direction by the spring 10 is designed so as to hit the corner of the hook portion 6 in advance. When further moved in the direction, the hook-like hooks 8A and 8B ride on the maximum dimension part of the hook part 6 while resisting the urging force of the spring 10 by the effect of the oblique contact surface as shown in FIG. . When the holder 7 is further moved in the direction of arrow M, as shown in FIG. 4- (c), hook-like hooks 8A and 8B finally get over the hook part 6, and hook-like hooks 8A and 8B hooking parts are springs. The collar 6 is automatically gripped by the urging force of 10, and preparation for liquid feeding is completed.

  The holder 7 is provided with a pusher gripping detection chip 13 that faces the pressing surface of the collar 6 and is capable of linear movement, and a detection lever 102 that is movable around the fulcrum 101 by pressing the pusher gripping detection chip 13 at the tip. Therefore, in the process of shifting from FIG. 4- (b) to FIG. 4- (c), the flange portion 6 pushes the pusher grip detection chip 13 in the direction opposite to the arrow M direction, and pushes the detecting lever 102 connected thereto. The magnet 104 is opposed to the magnetic plate 105 side, and an active signal is output to the magnetosensitive element 106. Therefore, if the output of the magnetic sensing element 106 is monitored by a control circuit provided inside the liquid feeding device 1, it is possible to detect whether the holder 7 has gripped the collar 6 or the pusher 5. .

  After the pusher 5 is automatically gripped in this way, liquid feeding is executed in accordance with a predetermined sequence. After the liquid feeding is completed, the empty container 2 is replaced and the holder is moved to a predetermined position. Although it is necessary to perform the pull-back operation quickly, it is often more convenient to perform manual operation for such a request. Therefore, the gripping mechanism of the present invention is provided with manual release means as shown in FIG. In this figure, when the operator manually pushes the release button 11 in the direction of the arrow P, the oblique contact surface of the inner wall of the release button 11 that contacts the rear ends of the hooks 8A and 8B moves in the direction of the arrow P. The movement of reducing the distance between the rear ends of the hook-shaped hooks 8A and 8B against the urging force of the spring 10 is caused, so that the tip portions of the hook-shaped hooks 8A and 8B rotate about the rotation fulcrums 9A and 9B. As a result, the gripping of the buttocks 6 is released. At this time, as described above, when the release button 11 is pressed, the clutch mechanism is operated to release the engagement between the nut contained in the carriage 21 and the lead screw 20, and the holder 7 can be moved manually. Therefore, if the holder 7 is moved in the direction opposite to the arrow P direction while the release button 11 is pushed in the direction of the arrow P, the holder 7 is quickly moved toward the position at the start of liquid feeding simultaneously with the release of the gripping portion 6. It is possible.

  FIG. 6 is a block diagram showing only the main part as an example of a control circuit used for controlling a liquid delivery device equipped with the gripping mechanism of the present invention. 601 is a microprocessor, 602 is an operation / display panel, 603 is an initial setting input circuit, 604 is an alarm buzzer, 605 is an abnormal display red light, 617 is a motor drive circuit, 622 is a position information processing circuit of the carriage 21, Reference numerals 624A and 624B denote clamp drive circuits for the clamps 24A and 24B, respectively.

  When the operator finishes mounting the container 2 on the liquid delivery device 1 and prepares the liquid delivery path 25 and performs a liquid entry start key input from the operation / display panel 602, the microprocessor 601 first starts the clamp drive circuit 624A. A clamp command is output to 224B and 224B, and the liquid supply path 25 is closed by the clamps 24A and 24B. Thereafter, the microprocessor 601 outputs a rotation command to the motor drive circuit 617, rotates the drive motor 17, moves the carriage 21, and moves the holder 7 in the direction of arrow M in FIG. Further, as in the process shown in FIGS. 4B and 4C, the holder 7 is moved and the pusher 5 is gripped. During this time, the microprocessor 601 grasps the gripping state of the pusher 5 by monitoring the gripping detection signal of the magnetosensitive element 106 that changes in accordance with the gripping state of the pusher 5, and also uses the optical type provided in the carriage 21. The encoder signal signal generated from the sensor 22 is acquired via the position information processing circuit 622 so that the current position of the carriage 21 can be accurately grasped.

  As a result, even if the pusher comes off during liquid feeding, the removal can be detected instantaneously by the control circuit, and at the same time the liquid feeding is stopped, a warning is given to the doctor or nurse with the buzzer 604 or red light 605. It is possible to prevent the danger given to the patient. In addition, as an embodiment of the present invention, the liquid feeding device 1 that automatically executes the gripping of the pusher 5 and manually releases the gripping has been described as an example, but it can also be applied to a general manual liquid feeding device. Is obvious and has a similar effect.

  As described above, in the present invention, the pusher gripping state is maintained during the liquid feeding operation in which the liquid stored in the container having the liquid feeding part at one end is pushed out by the pusher from the other end side according to the control by the control circuit incorporated in the apparatus. Since there is a means to constantly monitor and transmit the gripping state signal to the control circuit with high reliability, if the pusher is removed from the gripping mechanism for any reason, the medical action in the device is stopped. Since it is possible to issue an abnormality alarm to a manager such as a doctor or nurse, it is very useful in that a safe medical device can be provided with a simple and inexpensive configuration. is there.

  It can be used for medical devices such as push-out type liquid feeders and syringe pumps that feed the liquid stored in the container in advance with a pusher. It can be applied to applications that require special treatment.

It is explanatory drawing which showed the implementation method of the holding | grip detection apparatus of this invention mounted in the liquid feeding apparatus. Example 1 It is explanatory drawing which showed the relative positional relationship of the magnet seen from the arrow direction V of FIG. It is explanatory drawing which showed the obstruction | occlusion state of the liquid feeding path by a clamp. It is explanatory drawing which showed the automatic holding process with respect to a presser with the liquid feeding apparatus carrying the holding | grip detection apparatus of this invention. It is explanatory drawing which showed the state which released the holding | grip with respect to a pusher with the liquid feeding apparatus carrying the holding | grip detection apparatus of this invention. It is explanatory drawing which showed the main control circuits of the liquid feeding apparatus carrying the holding | grip detection apparatus of this invention with the block diagram.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Liquid supply apparatus 2 Container 5 Pusher 6 Eaves part 7 Holder 8A, 8B Hook hook 10 Spring 11 Release button 13 Pusher grip detection chip 14 Guide rod 17 Drive motor 20 Lead screw 21 Carriage 22 Optical sensor 23 Linear encoder 24 Clamp 102 Detection lever 104 Magnet 105 Magnetic plate 106 Magnetosensitive element 601 Microprocessor 604 Buzzer 605 Red light

Claims (2)

Whether or not the pusher is gripped by a gripping mechanism that grips the pusher in a device that pushes out liquid stored in a container having a liquid feeding part at one end with a pusher from the other end according to control by a control circuit incorporated in the device A gripping detection apparatus comprising: a sign signal transmission means for wirelessly transmitting a sign signal corresponding to the control signal to the control circuit by magnetic generation. The marking signal transmission means includes a magnetic plate extending opposite to the moving direction of the gripping mechanism and a magnetosensitive element on a facing surface, and depending on whether the pusher is gripped toward the magnetic plate. The grip detection device according to claim 1, further comprising a magnet that is in close proximity to and away from, and that converts the state of proximity to and away from the magnet into an electrical signal by the magnetosensitive element.

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