JP2017217222A - Air motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air motor whose rotation is easy to control.SOLUTION: A second chamber R2 incorporating a cylinder 16 of a brake 9 is positioned on the upstream side of a first chamber R1 incorporating an impeller 2 and it is possible to cause the pressure of air E to act on the cylinder 16 before acting on the impeller 2. As a result, the timing of the brake 9 is not delayed and the rotation can be controlled further accurately.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an air motor, and more particularly to an air motor suitable for use in a medical field where countermeasures against electromagnetic fields are required.

  Attempts have been made to perform image-guided surgery while installing MRI in the operating room and taking MRI images during surgery. In the operating room where the MRI is installed, if electric noise such as electromagnetic waves is generated from the medical device, the MRI image is adversely affected. Therefore, the electric motor cannot be used for the medical device used in the operating room.

  Therefore, an air motor that is driven by a compressed gas such as air is used. This type of air motor has an impeller that rotates with compressed gas, and has a structure in which power is obtained from an output shaft formed at the center of rotation of the impeller. In medical equipment, it is required to obtain not only motive power but also a necessary amount of rotation accurately, so a brake is combined with an impeller.

  The brake is always energized in the direction in contact with the impeller, and in a state where compressed gas is not supplied to the impeller, the brake contacts the impeller and stops rotating. The brake is integrally formed with a cylinder located on the downstream side of the impeller, and the pressure of the exhaust gas that has passed through the impeller acts on the cylinder so that the cylinder moves in a direction away from the impeller together with the brake so that the impeller can rotate. Become. When the supply of the compressed gas is stopped, the exhaust pressure is lost, and the brake is again brought into contact with the impeller by the urging force to stop the rotation. Thus, it rotates only at the time of supply of compressed gas, and when supply is stopped, rotation stops by a brake (for example, refer to patent documents 1).

Japanese Patent No. 3557174

  However, in such a related technology, since the cylinder for operating the brake is provided on the downstream side of the impeller, the operation timing of the brake is delayed with respect to the supply timing of the compressed gas, and the rotation control is accordingly performed. It was difficult.

  The present invention has been made paying attention to such related technology, and an object of the present invention is to provide an air motor that can be easily controlled for rotation.

  According to a first aspect of the present invention, an impeller having an output shaft as a center is rotatably housed, and a normal blowout that allows a compressed gas to be blown to the impeller to rotate the impeller in a forward direction and a reverse direction, respectively. The brake is connected to the downstream end of the road and the reverse blow-off path, and an exhaust port for discharging the compressed gas after the rotational force is applied to the impeller is formed, and the brake contacts the impeller with a predetermined urging force. Is connected to the upstream end of the normal blow-out path and the reverse blow-out path, and the downstream end of the positive supply path and the reverse supply path are selectively connected to either one of them. A cylinder that is integrated with the brake and that can move in the direction of contact with and away from the impeller of the brake is housed. The cylinder attaches the brake to the upstream end of the forward / reverse air supply path and the downstream end of the forward / reverse air supply path. It can be closed by force and pressure is applied to either the forward or reverse air supply path. Only when gas is supplied, the brake moves in a direction away from the impeller against the urging force and opens each upstream end of the forward / reverse air supply path and each downstream end of the forward / reverse air supply path. And a second chamber that allows a flow of compressed gas to the first chamber side.

  According to a second aspect of the present invention, a third chamber is formed in the middle of the normal air supply path and the reverse air supply path, and the normal air supply path and the reverse air supply path are selectively provided in the third chamber. A block that can be closed is movably stored, and the block is moved to the other side by the pressure of compressed gas supplied to either one of the normal air supply path and the reverse air supply path, and only the other side is blocked. Features.

  According to the third aspect of the present invention, the block is moved by engaging the wall portion of the third chamber on both the normal air supply path side and the reverse air supply path side of the block when the normal air supply path or the reverse air supply path is closed. And a stopper that exposes the side surface of the block on the closed side is formed.

  The fourth aspect of the present invention is characterized in that the stopper closes the forward or reverse air supply path on the same side when the block blocks either the normal air supply path or the reverse air supply path.

  The fifth aspect of the present invention is characterized in that a weight reducing hole is formed at a symmetrical position around the output shaft of the impeller.

  The sixth aspect of the present invention is characterized in that the downstream ends of the forward blowing path and the reverse blowing path are branched into a plurality and connected to the first chamber.

  According to the first aspect of the present invention, the second chamber containing the brake cylinder is located on the upstream side of the compressed gas from the first chamber containing the impeller, and the pressure of the compressed gas acts on the impeller. Since it can be applied to the cylinder before it is operated, there is no delay in brake timing, and more accurate rotation control can be performed.

  According to the second aspect of the present invention, the block housed in the third chamber is automatically moved by the pressure of the supplied compressed gas, and is supplied to the second chamber in order to close the non-supply side. It is possible to prevent a part of the compressed gas from flowing back through the normal air supply path or the reverse air supply path that is not on the supply side.

  According to the third aspect of the present invention, when the normal air supply path or the reverse air supply path is closed by the block, the movement is restricted by the stopper and the side surface on the closed side of the block is exposed. When the gas is supplied again, the pressure of the compressed gas acts in the direction of pushing the exposed side surface, and the block can be reliably moved to the closing side.

  According to the fourth aspect of the present invention, when the stopper closes either the normal air supply path or the reverse air supply path by the block, the normal air outlet or the reverse air outlet on the same side is closed. The flow of compressed gas on the supply side is ensured by preventing excessive flow of compressed gas into the channel or the reverse outlet.

  According to the fifth aspect of the present invention, since the weight reduction hole is formed in the impeller, the impeller becomes lightweight, and when the impeller comes into contact with the brake, the impeller prevents excessive rotation due to the inertia of the impeller. The car can be stopped reliably.

  According to the sixth aspect of the present invention, the downstream ends of the forward outlet and the reverse outlet are branched into a plurality and connected to the first chamber, so that compressed gas is blown against the impeller from a plurality of directions. And the rotation of the impeller can be stabilized.

Sectional drawing which shows the air motor which concerns on 1st Embodiment. Sectional drawing which shows the air motor to which the compressed gas to the normal rotation direction was supplied. Sectional drawing which shows the air motor to which the compressed gas to the reverse rotation direction was supplied. Sectional drawing which shows the bottom face of a 2nd chamber. Sectional drawing which shows a 1st chamber. Sectional drawing which shows the air motor which concerns on 2nd Embodiment. Sectional drawing which shows the 1st chamber of 2nd Embodiment.

  1-5 is a figure which shows the air motor 1 which concerns on 1st Embodiment of this invention.

  Below, the case where air (compressed gas) E is used as a drive fluid is demonstrated, and the structure toward the upstream from the downstream of the flow of the air E is demonstrated in order. The first chamber R1 defines a cylindrical first space and is located on the most downstream side, and the impeller 2 is accommodated therein. The impeller 2 has a disk shape having blades around it, and an output shaft 3 is formed at the center. The impeller 2 has two fan-shaped weight reduction holes 4 formed at symmetrical positions around the output shaft 3 (four in total).

  The impeller 2 has an output shaft 3 supported inside the first chamber R <b> 1 via a bearing 5, and can rotate in the forward and reverse directions around the output shaft 3.

  As shown in FIG. 5, the downstream ends 7a and 7b of the forward outlet 6a and the reverse outlet 6b are formed on one end side of the first chamber R1, respectively. And the impeller 2 can be rotated in the direction according to the blowing direction of the air E by blowing the air E toward the impeller 2 from each downstream end 7a, 7b. In FIG. 5, the white arrow is the forward direction, and the black arrow is the reverse direction. The air E that has rotated the impeller 2 is discharged from an exhaust port 8 formed on the opposite side of each downstream end 7a, 7b in the first chamber R1. The output shaft 3 of the impeller 2 is combined with a mechanism such as a medical device, and the rotation of the output shaft 3 gives a necessary amount of power to the device.

  A brake 9 is also housed in the first chamber R1. The brake 9 has a cup shape that can freely come into contact with a peripheral portion other than the weight reducing hole 4 of the impeller 2. A connecting shaft 10 is formed at the center of the brake 9, and the connecting shaft 10 is slidably supported, so that the brake 9 can be brought into and out of contact with the impeller 2. The connecting shaft 10 is provided with a spring 11 and urges the brake 9 so as to always contact the impeller 2. The impeller 2 can rotate only when the brake 9 is separated from the impeller 2, and the rotation is stopped when contacting the brake 9.

  The forward outlet 6a and the reverse outlet 6b extend upstream of the air E and are connected to the second chamber R2. The forward outlet 6a and the reverse outlet 6b pass through the second chamber R2 once and are connected to the second chamber R2 in a state of being largely detoured upstream.

  The second chamber R2 defines a cylindrical second space, and the bottom surface 12 has upstream ends 13a and 13b of a forward outlet 6a and a reverse outlet 6b as shown in FIG. The downstream ends 15a and 15b of the reverse air supply path 14b are connected. The forward air outlet 6a, the reverse air outlet 6b, the normal air supply passage 14a, and the reverse air supply passage 14b each have a hollow shape with a square cross section.

  The connecting shaft 10 of the brake 9 is also inserted into the second chamber R2. The connecting shaft 10 of the brake 9 inserted into the second chamber R2 is integrated with a disk-like cylinder 16 accommodated in the second chamber R2. Accordingly, the cylinder 16 can also freely reciprocate integrally in the direction in which the brake 9 contacts and separates from the impeller 2 (vertical direction). A substantially sealed space is formed by the cylinder 16 and the bottom surface 12 of the second chamber R2.

  The normal air supply path 14a and the reverse air supply path 14b extend further upstream from the second chamber R2, and a third chamber R3 that defines a third space is formed in the middle. The third chamber R3 has a structure in which the normal air supply path 14a and the reverse air supply path 14b are communicated, and the normal air supply path 14a and the reverse air supply path 14b are bent in a crank shape in the third chamber R3, and from the third chamber R3. The interval between the upstream side and the downstream side is wider than the downstream side. Upstream ends 17a and 17b are formed at the front ends of the wide positive air supply passage 14a and the reverse air supply passage 14b.

  A block 18 is housed in the third chamber R3 so as to be movable toward the normal air supply path 14a and the reverse air supply path 14b. Shafts 19a and 19b penetrating the wall of the third chamber R3 are formed on both sides of the block 18, and stoppers 20a and 20b are formed at the ends of the shafts 19a and 19b, respectively.

  The stoppers 20a and 20b are larger in diameter than the shafts 19a and 19b, and restrict the movement amount of the block 18 by engaging with the wall of the third chamber R3. The block 18 moves by a width capable of selectively closing the normal air supply path 14a and the reverse air supply path 14b on the downstream side of the third chamber R3 by engaging the stoppers 20a and 20b. When the block is closed, it does not move any more, and the side surfaces 21a and 21b of the block 18 on the closed side are necessarily exposed.

  In addition, there are a detoured forward blowing path 6a and a reverse blowing path 6b at the positions of the stoppers 20a and 20b, and insertion holes 22a and 22b are also formed at positions corresponding to the stoppers 20a and 20b.

  When the block 18 closes either the normal air supply path 14a or the reverse air supply path 14b, the stoppers 20a and 20b are inserted into the insertion holes 22a and 22b of the normal air outlet path 6a or the reverse air outlet path 6b on the same side. Is inserted to close the normal air outlet 6a or the reverse air outlet 6b.

  The insertion holes 22a and 22b have shapes that match the stoppers 20a and 20b, and the insertion holes 22a and 22b themselves are also blocked by inserting a part of them into the insertion holes 22a and 22b.

  The upstream end 17a, 17b of the normal air supply path 14a and the reverse air supply path 14b is used by the air motor 1 via a small solenoid valve (not shown because the electromagnetic noise of this small solenoid valve is small) and a tube. Connected to an air pump (not shown) installed outside the room. Since the air pump is installed outside, high-frequency electromagnetic noise generated from the air pump can be completely blocked.

  When the air motor 1 is used, either a normal air supply path 14a or a reverse air supply path 14b is selected with a small solenoid valve, and the air E is supplied from the upstream end 17a, 17b of the selected one, thereby making the blade The vehicle 2 rotates forward or backward, and necessary power is obtained from the output shaft 3 according to the amount of rotation.

  FIG. 2 shows a case where air E is supplied to the positive air supply path 14a.

  Immediately before the air E is supplied, when the air E is supplied to the positive air supply path 14a in the state of FIG. 1, the side surface 21a on the side of the positive air supply path 14a of the block 18 is exposed, so that the air E The pressure acts in the direction of pushing the side surface 21a, and moves the block 18 toward the reverse air supply path 14b.

  Even if the block 18 moves to the reverse air supply path 14b side, the stopper 20a engages with the wall part of the third chamber R3 on the normal air supply path 14a side, so that the block 18 is moved to the opposite end of the third chamber R3. Instead, it stops just at the position where the normal air supply path 14a is opened and the reverse air supply path 14b is closed, and the side surface 21b of the reverse air supply path 14b is kept exposed.

  The stopper 20a engaged with the wall of the third chamber R3 has a tip located in the insertion hole 22a, and the insertion hole 22a itself is kept closed by the stopper 20a. Since the other stopper 20b is inserted into the insertion hole 22b of the reverse blowing path 6b, the reverse blowing path 6b is closed and the insertion hole 22b itself is also closed.

  Since the regular air supply path 14a is opened, the air E is supplied into the second chamber R2 from the downstream end 15a of the regular air supply path 14a. The static pressure of the air E supplied into the second chamber R2 acts on the cylinder 16 first and raises the cylinder 16 against the urging force of the spring 11. When the cylinder 16 is raised, all the openings in the bottom surface 12 of the second chamber R2 are opened.

  The air E flows into the second chamber R2 from the downstream end 15a of the normal air supply path 14a and tries to enter the other three passages, but the reverse air supply path 14b is blocked by the block 18 and reversely blown out. Since the path 6b is closed by the stopper 20b, the air E flows only to the front outlet path 6a side.

  That is, since the block 18 closes the reverse air supply path 14b that is not on the supply side, it is possible to prevent the air E from flowing back through the block 18 and the stopper 20b also causes the air E to be extraneous into the reverse air discharge path 6b. In order to prevent the inflow, the air E flows only on the necessary front outlet 6a side.

  The air E that has flowed into the normal blow-out path 6a is blown from the downstream end 7a to the impeller 2 in the first chamber R1, and the impeller 2 is rotated in the forward rotation direction by the pressure gradient. The rotational force of the impeller 2 in the forward rotation direction is taken out from the output shaft 3, and the combined equipment can be operated. The air E after rotating the impeller 2 is discharged from the exhaust port 8 to the outside.

  When the necessary amount of rotation is obtained and the impeller 2 is stopped, the supply of the air E to the regular air supply path 14a is stopped. Then, since the pressure of the air E acting on the cylinder 16 is lowered, the cylinder 16 is lowered together with the brake 9 by the urging force of the spring 11, the cylinder 16 closes all the openings of the second chamber R2, and the brake 9 The rotation of the impeller 2 is stopped in contact with the car 2.

  The second chamber R2 containing the cylinder 16 integrated with the brake 9 is located on the upstream side of the flow of the air E relative to the first chamber R1 containing the impeller 2, and causes the pressure of the air E to act on the impeller 2. Since it can act on the cylinder 16 before, there is no timing delay of the brake 9, and more accurate rotation control can be performed.

  When the impeller 2 is braked by the brake 9, the impeller 2 is lightened by the weight reduction hole 4, so that the impeller 2 can be prevented from rotating too much due to the inertia of the impeller 2, and the rotation of the impeller 2 can be accurately performed. Can be controlled.

  When the impeller 2 is rotated in the reverse direction, the air E may be supplied to the reverse air supply path 14b as shown in FIG. By doing so, an operation opposite to the forward rotation direction occurs, and the impeller 2 can be rotated in the reverse rotation direction.

  6 and 7 are views showing a second embodiment of the present invention. This embodiment includes the same components as those in the first embodiment. Therefore, components similar to those are denoted by common reference numerals and redundant description is omitted.

  In the air motor 23 according to this embodiment, the forward air outlet 6a and the reverse air outlet 6b each have downstream ends 7a, 7b, 24a, and 24b branched into two, and the first chamber R1 has connection points thereof. Two were provided.

  Connection ports of the respective downstream ends 7a, 7b, 24a, 24b are formed at the opposing positions of the first chamber R1, and the air E is blown out so as to act on the impeller 2 from the opposing positions in the same rotational direction. The exhaust port 25 is also formed on the opposite side of the exhaust port 8, and the exhaust from each downstream end 7a, 7b, 24a, 24b is performed smoothly. By blowing the air E from the plural directions to the impeller 2 in this way, the rotation of the impeller 2 can be further stabilized.

  In each of the above embodiments, the air E is taken as an example of the compressed gas, but the present invention is not limited to this, and nitrogen gas or other gas may be used.

DESCRIPTION OF SYMBOLS 1, 23 Air motor 2 Impeller 3 Output shaft 4 Weight reduction hole 6a Normal blowout path 6b Reverse blowout path 8, 25 Exhaust port 9 Brake 14a Positive supply path 14b Positive supply path 16 Cylinder 18 Block 20a, 20b Stopper E Air (Compressed gas)
R1 1st chamber R2 2nd chamber R3 3rd chamber

Claims (6)

An impeller having an output shaft as a center is rotatably accommodated, and a downstream end of a forward blow path and a reverse blow path that can freely blow compressed gas to the impeller to rotate the impeller in the forward direction and the reverse direction, respectively. A first chamber that is connected to each other, has an exhaust port that discharges compressed gas after a rotational force is applied to the impeller, and stores a brake that contacts the impeller with a predetermined urging force;
The upstream ends of the forward and reverse air outlets are connected, and the downstream ends of the normal and reverse air supply passages that selectively supply compressed gas to one of them are connected, and the brake blades are integrated with the brake. A cylinder that is movable in the direction of contact with and away from the vehicle is housed, and the cylinder can block the upstream end of the forward / reverse air discharge path and the downstream end of the forward / reverse air supply path by the urging force of the brake and forward / reverse. Only when compressed gas is supplied to one of the air supply paths, it moves in the direction away from the impeller with the brake against the urging force, and the upstream ends of the forward / reverse outlet paths and the forward / reverse air supply paths An air motor comprising: a second chamber that opens each downstream end of the first chamber and allows a flow of compressed gas to the first chamber side. A third chamber is formed in the middle of the normal air supply path and the reverse air supply path.
A block capable of selectively closing the normal air supply path and the reverse air supply path is movably accommodated in the third chamber, and the block is supplied to either the normal air supply path or the reverse air supply path. 2. The air motor according to claim 1, wherein the air motor is moved to the other side by the pressure of the compressed gas and is closed only on the other side.   Engage with the wall of the third chamber to restrict the movement of the block on both the normal air supply path side and the reverse air supply path side of the block when the normal air supply path or the reverse air supply path is closed. The air motor according to claim 2, wherein a stopper for exposing a side surface of the air motor is formed.   4. The air motor according to claim 3, wherein the stopper closes the normal blow-out path or reverse blow-out path on the same side when either the normal air supply path or the reverse air supply path by the block is closed.   The air motor according to any one of claims 1 to 4, wherein a weight reduction hole is formed at a symmetrical position around the output shaft of the impeller. The air motor according to any one of claims 1 to 5, wherein downstream ends of the normal blow-out path and the reverse blow-out path are branched into a plurality and connected to the first chamber.

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