JP6343137B2 - Exhaust system - Google Patents

Description

  The present invention relates to an exhaust device that has a work chamber provided on the front surface with a lifting door that can be opened downward by pulling upward, and exhausts air in the work chamber.

  Conventionally, when an experiment or the like using a medicine is performed, a toxic gas may be generated from the medicine in the human body. Therefore, in an experiment using chemicals, it is common to use an exhaust device provided with a box-shaped work chamber provided with a lifting door on the front and a predetermined isolation chamber isolated from the outside air. Thus, it is possible to perform an experiment in the work chamber by accessing from the open portion of the lift door, and to exhaust the gas in the work chamber to the isolation chamber without leaking to the outside air.

  As an example of the exhaust device, there is one in which a handle provided with a recessed groove (projecting piece) for handling and an extending piece extending to the lower end side of the handle is attached along the lower surface of the lifting door. This handle has an upper guide surface that deflects the airflow that flows along the rear surface of the lifting door located in the processing chamber (working chamber) backward and obliquely downward, and an airflow that flows into the processing chamber flowing from below the lifting door. And a lower guide surface directed along the two, the two air flows are joined together without causing turbulent flow or vortex flow, and smoothly circulated in the processing chamber. (For example, refer to Patent Document 1).

Japanese Patent No. 4456390 (pages 4, 5 and 3)

  However, in Patent Document 1, when the length of the extended piece is set to be long, it flows from the outside toward the front face of the handle when the elevator door is raised or lowered or when a person passes near the front face of the elevator door. When an air current is generated, the air current collides with the extended piece, and a part of the air current moves along the groove portion of the handle to form a vortex, and this vortex flows is retained between the extended piece and the groove portion. The air in the vicinity of the handle is entrained, the flow of air flowing into the processing chamber through the open portion of the lift door is obstructed, and the air in the processing chamber may leak into the outside air. In addition, when the length of the extended piece is short, there is a problem that a sufficient gap is not formed between the groove and the bottom plate of the working chamber when the elevator door is closed, making it difficult to operate the elevator door. It was.

  The present invention has been made paying attention to such a problem, and while making the operation of the elevating door easy, the flow of air flowing into the working chamber even if the turbulence of the airflow occurs in the vicinity of the lower end portion of the elevating door. An object of the present invention is to provide an exhaust device that prevents the air in the working chamber from leaking to the outside air.

In order to solve the above-described problem, an exhaust device of the present invention includes:
An exhaust device that has a work chamber provided on the front surface that can be opened downward by pulling upward, and exhausts air in the work chamber,
The lower end portion of the elevator door is provided with an extending piece extending below the elevator door, and a protruding piece protruding substantially horizontally from the upper part of the extending piece to the front surface of the elevator door by a predetermined length. And
The length of the extended piece is not less than 1.5 times the predetermined length of the protruding piece and not more than twice the predetermined length of the protruding piece.
According to this feature, the turning radius of the vortex formed when the airflow flowing on the front surface of the extended piece moves along the extended piece and the protruding piece is substantially the same as the length of the protruding piece. Since the length of the piece is not more than twice the predetermined length of the protruding piece, the length of the extended piece is equal to or less than the rotating diameter of the vortex, so The vortex flow is urged to flow into the work chamber via the open portion of the lift door when the lift door is opened, and leakage of the air in the work chamber to the outside air can be prevented. Furthermore, since the length of the extended piece is at least the predetermined length of the protruding piece, a sufficient gap is formed between the protruding piece and the bottom plate of the working chamber even when the elevator door is closed. The elevator door can be easily operated by putting a finger in the gap and hooking it on the protruding piece. For example, even if the extending piece and the protruding piece are formed of an opaque member, the extending piece is not more than twice the predetermined length of the protruding piece. A wide area where the inside of the working room can be visually confirmed can be secured.

The extending piece and the projecting piece are formed on a gripping member attached so as to surround a lower end side of the lifting door, and the gripping member is directed downward at an upper rear side facing the working chamber. It protrudes gradually from the said raising / lowering door, It has the concave inclined surface of side view concave shape, It is characterized by the above-mentioned.
According to this feature, the airflow flowing down along the rear surface of the lift door is guided rearward along the concave inclined surface, and the airflow and the airflow flowing in from the outside do not merge in the vicinity of the open portion of the lift door. Therefore, it is possible to suppress the occurrence of turbulent flow in the vicinity of the open portion of the lift door.

The gripping member has a linearly inclined surface extending linearly toward the concavely inclined surface at the lower rear side facing the working chamber.
According to this feature, part of the vortex flowing into the work chamber when the lift door is opened moves obliquely upward along the linear inclined surface. The airflow flowing down toward the open portion of the door can be pushed up to prevent the airflow from flowing out.

The gripping member is integrally formed of a soft resin, and a gap is formed in the lower end side of the extended piece.
According to this feature, the gripping member is integrally formed of a soft resin and a gap is formed at the lower end side of the extended piece. Since the piece elastically deforms and cushions the gap, not only can the injury be prevented, but the extended piece does not damage the bottom plate of the working chamber when the elevator door is closed.

It is a perspective view which shows the exhaust apparatus in Example 1. FIG. It is side sectional drawing which similarly shows an exhaust apparatus. It is a perspective view which shows the time of attachment to the raising / lowering door of a holding member. It is a sectional side view which shows the state in which the holding member was attached to the raising / lowering door. (A)-(c) is a sectional side view which shows the flow of the air of the holding member vicinity in steps when an airflow generate | occur | produced toward the front side of the holding member. (A) is a sectional side view showing a state where the elevator door is raised, and (b) is a sectional side view showing a state where the elevator door is lowered. It is a sectional side view which shows the state which pinched | interposed the finger at the time of the descent | fall of an elevator door. (A) is a sectional side view showing a modification of the gripping member, and (b) is a sectional side view showing a state where an air flow is generated from the state of (a) toward the front side of the gripping member.

  EMBODIMENT OF THE INVENTION The form for implementing the exhaust apparatus which concerns on this invention is demonstrated below based on an Example.

  An exhaust device according to Embodiment 1 will be described with reference to FIGS. As shown in FIG. 1, the exhaust device 1 is mainly introduced in educational institutions and research facilities, and is used when harmful gases are generated in chemical experiments using chemicals or when handling volatile harmful substances. Is done. As shown in FIG. 1 and FIG. 2, the exhaust device 1 includes a base 2 provided with opening doors 2 a and 2 a on the front surface, and a box-shaped housing 3 opened on the front surface. It is mounted on the base 2 and assembled.

  The housing 3 includes a bottom plate 3a, a top plate 3b, a back plate 3c, and side plates 3d and 3d. The top plate 3b is provided with an exhaust port 4. The exhaust port 4 is isolated from outside air (not shown). It is connected to a predetermined isolation room. The isolation chamber can purify the air sucked from the exhaust port 4.

  Further, a translucent fixing plate 5 is fixed to the upper portion of the front opening of the housing 3, and a translucent elevating door that slides up and down is provided on the front side of the fixing plate 5. An elevating plate 6 is provided. Specifically, the side plates 3d and 3d are formed with concave grooves 7 and 7 (only one is shown) facing each other along the vertical direction, and both end portions of the elevating plate 6 are formed in the concave grooves 7 and 7 respectively. By fitting, the elevating plate 6 can slide up and down along the concave grooves 7 and 7. The inside of the housing 3 partitioned by the bottom plate 3a, the top plate 3b, the back plate 3c, the side plates 3d and 3d, the fixing plate 5 and the elevating plate 6 is a working chamber 8 for performing chemical experiments using chemicals. .

  By raising the elevating plate 6 upward, the lower part of the opening of the housing 3 can be opened, and the experiment is conducted by accessing the inside of the work chamber 8 from the outside of the housing 3 through the opening 30 of the housing 3. Can be done. As described above, since the fixed plate 5 and the lift plate 6 have translucency, experiments and the like can be performed while visually confirming the inside of the work chamber 8 from the outside.

  Further, the housing 3 is provided with an intake passage 9 that extends obliquely upward from the lower portion on the front side and communicates with the work chamber 8, so that the lift plate 6 can be interposed through the intake passage 9 even when the lift plate 6 is closed. The outside air can be guided into the work chamber 8.

  As shown in FIGS. 3 and 4, a gripping member 10 surrounding the lower end side of the elevating plate 6 is attached to the lower end portion of the elevating plate 6 of the exhaust device 1. The gripping member 10 includes a fitting member 11 that is fitted to the lower end portion of the elevating plate 6, and a surrounding member 12 that is attached so as to wrap the outer peripheral surface of the fitting member 11 as a framework.

  The fitting member 11 includes a first plate body 13, a second plate body 14, and a third plate body 15 that are extruded using a material such as metal or hard resin. The first plate 13 includes a front standing portion 13a extending along the front surface 6a of the elevating plate 6, a front projecting portion 13b projecting obliquely downward from the upper end of the front standing portion 13a, and a front standing portion 13a. And a bottom surface portion 13c extending rearward from the lower end. The second plate body 14 has an L-shaped standing portion whose bottom surface extending from the bottom surface portion 13c along the rear surface 6b of the elevating plate 6 is bent rearward. The rear surface of the rear standing portion has a lower surface rearward. A bent L-shaped third plate 15 is fixed. The fitting member 11 is formed by connecting the first plate body 13, the second plate body 14, and the third plate body 15, but may be formed by one member.

  As shown in FIG. 4, the surrounding member 12 is an extruded soft resin, and includes a horizontal portion 12a extending substantially horizontally from the front end portion of the front protruding portion 13b toward the front standing portion 13a, and a horizontal portion. An extended portion 12b extending downward along the front standing portion 13a from 12a, a lower end portion 12c having a void 16 in which the inside is hollowed out, and a straight line shape in cross section protruding rearward and upward from the lower end portion 12c The inclined portion 12d, the concave inclined portion 12e having a concave shape in sectional view, which gradually protrudes forward from the vicinity of the third plate 15 of the inclined portion 12d toward the upper surface of the rear surface 6b of the elevating plate 6, and the second plate 14. And an adhesive engaging portion 12f that is adhesively engaged with the upper tip portion of the. In addition, an adhesive engaging portion 12g that is adhesively engaged with the front standing portion 13a is provided at the upper front end of the horizontal portion 12a.

  As described above, the gripping member 10 has the contact portion 12g of the horizontal portion 12a bonded and engaged with the portion of the front projecting portion 13b that is bent toward the front standing portion 13a and the second plate body 14 is engaged. The surrounding member 12 is mounted and formed on the fitting member 11 by causing the adhesive engaging portion 12f to be adhesively engaged with the upper end portion of the fitting member 11.

  As shown in FIG. 3, the gripping member 10 is fitted to the lower end portion of the lifting plate 6 by inserting the lifting plate 6 into the gap between the front standing portion 13 a and the rear standing portion of the second plate body 14. Combined. After the gripping member 10 is fitted to the lower end portion of the lifting plate 6, an adhesive or the like is poured into the gap between the gripping member 10 and the lifting plate 6 to be firmly fixed.

  As shown in FIG. 4, the front projecting portion 13 b of the gripping member 10 functions as a projecting piece that a user can hang a finger on when raising and lowering the elevating plate 6, and the extending portion 12 b It functions as a spacer between the protruding piece and the bottom plate 3 a of the housing 3 when the elevating plate 6 is closed.

  In this gripping member 10, the length B of the extending portion 12b is twice the length A of the front protruding portion 13b. In other words, the length A of the front projecting portion 13b: the length B of the extending portion 12b = 1: 2. Thus, since the length B of the extending portion 12b is twice the length A of the front protruding portion 13b, the front protruding portion 13b and the housing 3 can be connected even when the lifting plate 6 is closed. A sufficient gap is formed between the bottom plate 3a, and the elevating plate 6 can be easily operated by putting a finger into the gap and hooking it on the front protrusion 13b. Moreover, the area | region which can visually recognize the inside of the working chamber 8 via the raising / lowering board 6 is minimized by minimizing the ratio of the length A of the front protrusion part 13b and the length B of the extension part 12b to 1: 2. Can be secured widely.

  Next, it is assumed that an airflow R flowing toward the front surface side of the gripping member 10 is generated due to a person passing near the front surface of the exhaust device 1 (see FIG. 5A), and the lifting plate A smoke experiment is performed in which smoke is applied from the front side toward the gripping member 10 attached to 6, and the result (the flow of air in the vicinity of the gripping member 10) is described. Hereinafter, a state in which the elevating plate 6 is in the open state and the open portion 30 is formed will be described.

  As shown in FIG. 5 (b), a part of the airflow R collides with the extending portion 12b and moves along the horizontal portion 12a to become an airflow S that is a vortex, and other ones. The part flows into the working chamber 8 as the airflow T through the lower part 12 c of the gripping member 10. Further, a part of the airflow S is pushed upward as an airflow Sb from the front end of the front protrusion 13b. The air flow S stably rotates around a virtual point Z connecting a virtual line that hangs down from the front end of the front projecting portion 13b and a virtual line that extends horizontally from the central portion in the vertical direction of the extending portion 12b. To come.

  As described above, since the length B of the extending portion 12b is twice the length A of the front protruding portion 13b, the length B of the extending portion 12b is equivalent to the turning diameter of the airflow S. A part of the leading side of the airflow S flows into the working chamber 8 as the airflow Sa through the lower part of the lower end portion 12c, and the airflow S other than the airflow Sa again extends along the extending portion 12b and the horizontal portion 12a. To turn.

  Accordingly, as shown in FIG. 5C, the airflow S is prevented from staying between the extending portion 12 b and the front projecting portion 13 b, and the work chamber 8 is opened through the opening portion 30 of the lifting plate 6. As a result of being urged to flow into the air, the air flow Y directed from the inside of the work chamber 8 to the outside is pushed back, and leakage of air in the work chamber 8 to the outside air can be prevented.

  As shown in FIG. 5C, the airflow Sa flowing into the working chamber 8 flows along the bottom plate 3 a of the housing 3, and a part of the airflow Sa is provided behind the lower part of the gripping member 10. It moves obliquely upward along the linear inclined portion 12d.

  The airflow X flowing down along the rear surface 6b of the lift plate 6 in the work chamber 8 is guided rearward along the concave inclined portion 12e and pushed up by the airflow Sa moving obliquely upward along the linear inclined portion 12d. Therefore, the airflow X and the airflow Sa flowing along the bottom plate 3 a of the housing 3 do not merge in the vicinity of the open portion 30 of the lifting plate 6. Therefore, the turbulent flow accompanying the collision of the airflow X and the airflow Sa is prevented from occurring in the vicinity of the opening portion 30 of the lifting plate 6, and the flow of the airflow Y toward the opening portion 30 of the lifting plate 6 is reduced. Can weaken.

  As shown in FIG. 6A, when the elevating plate 6 is raised, air above the front projecting portion 13b is caught in the lower side of the horizontal portion 12a, thereby generating the airflow S described above. . Further, as shown in FIG. 6B, when the elevating plate 6 is lowered, the air on the lower side of the extending portion 12b is pushed up obliquely upward along the linear inclined portion 12d, and the elevating plate 6 It is possible to prevent the airflow X from flowing out by pushing up the airflow X flowing down along the rear surface 6b.

  Although not shown, when the smoke experiment was performed with the length of the extended portion set shorter than the front protruding portion 13b, the range in which the air flow R hits the front surface of the extended portion could not be sufficiently secured, It was found that a stable turbulent flow was formed. Further, it was found that when the smoke experiment was performed with the length of the extended portion set to be longer than twice the length of the front protruding portion 13b, a vortex was retained between the extended portion and the front protruding portion 13b. Accordingly, the length of the extending portion is set to be equal to or longer than the predetermined length A of the front protruding portion 13b and not more than twice the predetermined length A of the front protruding portion 13b.

  In addition, as shown in FIG. 7, the surrounding member 12 of the gripping member 10 is integrally formed of a soft resin, and the lower end portion 12 c of the surrounding member 12 is formed with a void 16 in which the inside is thinned. Therefore, even if the finger is sandwiched when the elevating plate 6 is lowered, the contact portion of the lower end 12c with the finger is elastically deformed and buffered by the gap 16 so that injury can be prevented. Further, when the elevating plate 6 is closed, the contact with the bottom plate 3a of the housing 3 is buffered, and the bottom plate 3a of the housing 3 is not damaged.

Modified example

  Next, a modified example of the gripping member will be described with reference to FIG. In addition, the same structure as the said Example and the overlapping structure are abbreviate | omitted.

  As shown in FIG. 8A, in the gripping member 100 of the present modification, the length C of the extended portion 120b is 1.5 times the length A of the front protruding portion 13b. According to this, when the airflow R described in the embodiment flows toward the front side of the gripping member 100, as shown in FIG. 8B, between the extended portion 120b and the front protruding portion 13b. Airflow S ′ is generated. This air flow S ′ rotates around a virtual point Z ′ connecting a virtual line that hangs down from the front end of the front projecting portion 13b and a virtual line that extends horizontally from the center in the vertical direction of the extending portion 120b. It is supposed to be.

  More specifically, since the length C of the extended portion 120b is 1.5 times the length A of the front protruding portion 13b, an imaginary line hanging from the front end of the front protruding portion 13b The airflow S ′ is set to be shorter than the imaginary line extending horizontally from the central portion in the vertical direction, and the airflow S ′ rotates stably while drawing a short elliptical orbit in the vertical direction.

  In addition, when the smoke experiment was performed by setting the length of the extended portion to 1.5 times or less the length A of the front protruding portion 13b, the length C of the extended portion 120b was set to the length of the front protruding portion 13b. It was found that the airflow S ′ becomes slightly unstable as compared with the case where the smoke experiment was performed at 1.5 times the height A.

  Accordingly, it has been found that the length of the extended portion is 1.5 times the length A of the front protruding portion 13b, so that an airflow S '(vortex) that rotates more stably can be formed. Thus, by setting the length C of the extended portion 120b to 1.5 times the length A of the front projecting portion 13b, a sufficient range can be secured for the airflow R flowing on the front surface of the extended portion 120b. And stable airflow S ′ can be formed, the occurrence of turbulent flow in the vicinity of the opening 30 of the lifting plate 6 can be prevented, and the airflow Sa ′ can be smoothly flowed into the working chamber 8, and the gripping member 100. Can be minimized.

  Further, as described in the above embodiment, the upper limit of the length of the extending portion that does not retain the airflow S ′ between the extending portion and the front protruding portion 13b is twice the length A of the front protruding portion 13b. Therefore, the extended portion is most preferably set to a length that is 1.5 to 2 times the length A of the front protrusion 13b.

  Although the embodiments of the present invention have been described with reference to the drawings, the specific configuration is not limited to these embodiments, and modifications and additions within the scope of the present invention are included in the present invention. It is.

  For example, in the above-described embodiment, the extending piece and the protruding piece are formed on the gripping member 10 attached so as to surround the lower end side of the elevating plate 6. In addition, the extending piece and the protruding piece may be separately fixed to the lower end side.

  Further, the surrounding member 12 is made of a soft resin, and the lower end portion 12c thereof has the void 16 in which the inside is hollowed out. However, the present invention is not limited to this. For example, the surrounding member 12 is formed of a hard material. A separate buffer member may be provided at the lower end of the member.

DESCRIPTION OF SYMBOLS 1 Exhaust device 3 Case 3a Bottom plate 6 Elevating plate (elevating door)
6a Front 6b Rear 8 Work chamber 10 Holding member 11 Fitting member 12 Enclosing member 12a Horizontal portion 12b Extension portion (extension piece)
12c Lower end 12d Straight slope (straight slope)
12e concave slope (concave slope)
13 1st board 13b Front protrusion part (protrusion piece)
14 Second plate 15 Third plate 16 Gap 30 Opening portion 100 Holding member 120b Extension portion R Airflow S Airflow (vortex)
Sa, Sb Airflow T, X, Y Airflow Z Virtual point

Claims (4)

An exhaust device that has a work chamber provided on the front surface that can be opened downward by pulling upward, and exhausts air in the work chamber,
The lower end portion of the elevator door is provided with an extending piece extending below the elevator door, and a protruding piece protruding substantially horizontally from the upper part of the extending piece to the front surface of the elevator door by a predetermined length. And
The length of the extended piece is 1.5 times or more of a predetermined length of the protruding piece and is 2 times or less of the predetermined length of the protruding piece. The extending piece and the projecting piece are formed on a gripping member attached so as to surround a lower end side of the lifting door, and the gripping member is directed downward at an upper rear side facing the working chamber. The exhaust device according to claim 1, wherein the exhaust device protrudes gradually from the elevating door and has a concave inclined surface having a concave shape in a side view. The exhaust device according to claim 2 , wherein the gripping member has a linear inclined surface extending linearly toward the concave inclined surface at a lower rear side facing the working chamber. The exhaust device according to claim 2 or 3 , wherein the gripping member is integrally formed of a soft resin, and a gap is formed in a lower end side of the extending piece.

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