Emergency stop valve

Abstract

The invention relates to shut-off valve for controlling flow of a pressurised gas. The shut-off valve comprising a body defining a passage extending between a gas inlet channel and a gas outlet channel, a sealing element, and an emergency stop mechanism. The sealing element arranged to, in a first position, close the passage, and in a second position, open the passage to allow gas to flow between the gas inlet channel and the gas outlet channel through the passage. The invention also relates to a method for controlling flow of a pressurised gas with a shut-off valve and a method for activating an emergency stop of a shut-off valve.

Claims

1. A shut-off valve for controlling flow of a pressurised gas, comprising: a body defining a passage extending between a gas inlet channel and a gas outlet channel; a sealing element arranged to, in a first position, close the passage, and in a second position, open the passage to allow a pressurised gas to flow between the gas inlet channel and the gas outlet channel through the passage; and an emergency stop mechanism configured to immediately move the sealing element into the first position upon actuation, thereby closing the passage to prevent the pressurised gas from flowing between the gas inlet channel and the gas outlet channel wherein the emergency stop mechanism comprises: a sliding spindle connected to the sealing element; a biasing element for biasing the sealing element in a direction towards the sliding spindle; a rotation spindle in rotational engagement with the sliding spindle; and an engagement member configured to prevent axial movement of the sliding spindle in relation to the rotation spindle when the shut-off valve is in a normal state and to allow axial movement of the sliding spindle in relation to the rotation spindle when the shut-off valve is in an emergency state.

2. The shut-off valve according to claim 1, wherein: the sliding spindle comprises a through hole for holding the engagement member; the rotation spindle comprises a recess adapted for receiving a portion of the engagement member when the shut-off valve is in the normal state; and the shut-off valve further comprises a pin member movably arranged in the sliding spindle and comprising a recess adapted for receiving a portion of the engagement member when the shut-off valve is in the emergency state.

3. The shut-off valve according to claim 2, wherein when the sealing element moves to the second position, the pin member moves in an axial direction to align its recess with the through hole of the sliding spindle and the recess of the rotation spindle, so that the engagement member moves out of the recess of the rotation spindle and into the recess of the pin member, thereby activating the emergency state of the shut-off valve by allowing axial movement of the sliding spindle and movement of the sealing element into the first position.

4. The shut-off valve according to claim 2, further comprising: a hand wheel connected to the pin member and the sliding spindle.

5. The shut-off valve according to claim 1, further comprising: a pin element at least partly arranged in the passage that connects the sliding spindle with the sealing element, wherein the biasing element is arranged for biasing a first end of the sealing element such that a second end of the sealing element is in contact with the pin element.

6. The shut-off valve according to claim 5, wherein the pin element comprises: a guide for guiding the pressurised gas between the gas inlet channel and the gas outlet channel when the sealing element is in the second position, the guide extending in a longitudinal direction of the pin element and being arranged to allow the pressurised gas to leave the passage in a radial direction of the pin element.

7. The shut-off valve according to claim 6, wherein the guide comprises a longitudinally extending recess formed in an outer surface of the pin element, the outer surface extending between a first axial end and a second axial end of the pin element.

8. The shut-off valve according to claim 5, wherein the pin element comprises a restrictor at its axial end, which is in contact with the sealing element.

9. The shut-off valve according to claim 8, wherein the restrictor surrounds the pin element in a circumferential direction and is tapering in an axial direction from the axial end, which is in contact with the sealing element.

10. The shut-off valve according to claim 5, wherein: the body comprises an inner threading; the rotation spindle is connected to the pin element via the sliding spindle and has an outer threading in engagement with the inner threading of the body; rotation of the sliding spindle rotates the rotation spindle in a first direction to move the sealing element from the first position to the second position via the pin element; and rotation of the sliding spindle in a second direction allows the sealing element to move from the second position to the first position via the biasing element.

11. The shut-off valve according to claim 10, wherein the inner threading and the outer threading each include high-pitched threading.

12. The shut-off valve according to claim 1, further comprising: a hand wheel connected to the sliding spindle.

13. The shut-off valve according to claim 1, further comprising: a lower spindle housing the sealing element and in connection with the biasing element.

14. The shut-off valve according to claim 1, wherein the gas inlet channel and the passage are arranged essentially perpendicular to each other, the gas outlet channel and the passage are arranged essentially perpendicular to each other, and the gas inlet channel and the gas outlet channel are arranged in parallel with a distance between them, the distance being bridged by the passage.

15. The shut-off valve according to claim 1, further comprising: a status indicator adapted to indicate a state of the shut-off valve.

16. A method for controlling flow of the pressurised gas with the shut-off valve according to claim 1, the method comprising: moving the sealing element from the first position to the second position to allow the pressurised gas to flow between the gas inlet channel and the gas outlet channel through the passage; and moving the sealing element from the second position to the first position to prevent the pressurised gas from flowing between the gas inlet channel and the gas outlet channel through the passage.

17. A method for activating the emergency stop mechanism of the shut-off valve according to claim 1, the method comprising: activating the emergency stop mechanism to cause the sealing element to immediately move into the first position, thereby closing the passage to prevent the pressurised gas from flowing between the gas inlet channel and the gas outlet channel.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above, as well as additional objects, features and advantages of the present invention, will be better understood through the following illustrative and non-limiting detailed description of embodiments of the present invention, with reference to the appended drawings, where the same reference numerals may be used for similar elements, and wherein:

(2) FIG. 1 is a top view of a hand wheel for a shut-off valve according to one exemplary embodiment of a first aspect of the invention.

(3) FIG. 2 is an overall cross sectional view of the shut-off valve.

(4) FIG. 3a is a cross sectional view of a portion of the shut-off valve, when in an open state.

(5) FIG. 3b is a cross sectional view of a portion of the shut-off valve, when in a closed state.

(6) FIG. 4a is a cross sectional view of a portion of the shut-off valve, when in the closed state.

(7) FIG. 4b is a cross sectional view of a portion of the shut-off valve, when in an emergency state.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

(8) FIG. 1 illustrates a hand wheel 1 for a shut-off valve 2 for controlling flow of a pressurised gas according to one exemplary embodiment of the invention. By rotating the hand wheel 1, the shut-off valve 2 is placed in an opened or a closed state. The shut-off valve 2 also has an emergency state which is triggered by pushing the hand wheel 1 downwardly in an axial direction thereof and which immediately places the shut-off valve 2 in the closed state.

(9) FIG. 2 gives a complete overview of the shut-off valve 2. The shut-off valve 2 comprises a body 3 defining a passage 4 which extends between a gas inlet channel 5 and a gas outlet channel 6, and a sealing element 7 arranged to, in a first position, close the passage 4, and in a second position, open the passage 4 to allow gas to flow between the gas inlet channel 5 and the gas outlet channel 6 through the passage 4. The shut-off valve 2 further comprises an emergency stop mechanism which upon actuation is adapted to immediately move the sealing element 7 into the first position, thereby closing the passage 4 to prevent gas from flowing between the gas inlet channel 5 and the gas outlet channel 6.

(10) The emergency stop mechanism comprises a sliding spindle 9 which is connected to the sealing element 7, a biasing element 10 for biasing the sealing element 7 in a direction towards the sliding spindle 9, a rotation spindle 11 in rotational engagement with the sliding spindle 9, and an engagement means 12 adapted to prevent axial movement of the sliding spindle 9 in relation to the rotation spindle 11 in a normal state and to allow axial movement of the sliding spindle 9 in relation to the rotation spindle 11 in the emergency state. Further, the shut-off valve 2 has a lower spindle 13 housing the sealing element 7. The lower spindle 13 is in direct connection with the biasing element 10.

(11) The sliding spindle 9 is constituted by a hollow cylinder and is adapted to receive a pin member 14, which is movably arranged in the sliding spindle 9. The sliding spindle 9 comprises a through hole 22 for holding the engagement means 12. The rotation spindle 11 comprises a recess 15 adapted for receiving a portion of the engagement means 12 in the normal state of the shut-off valve 2. The pin member 14 comprising a recess 16 adapted for receiving a portion of the engagement means 12 in the emergency state of the shut-off valve 2.

(12) In the specific embodiment disclosed in FIG. 2, the engagement means 12 comprises two ball members, Therefore, the sliding spindle 9 comprises one through hole 22 on each side thereof for holding the ball members 12. Further, the rotation spindle 11 comprises one recess 15 on each side thereof adapted for receiving a portion of the ball members 12 when the shut-off valve 2 is in the normal state, and the pin member 14 comprises one recess 16 one each side thereof adapted for receiving a portion of the ball members 12 when the shut-off valve 2 is in the emergency state.

(13) The shut-off valve 2 further comprises a pin element 17 arranged in the passage 4 which connects the sliding spindle 9 with the sealing element 7. Thus, the biasing element 10 is arranged for biasing a first end 18 of the sealing element 7 such that a second end 19 of the sealing element 7 is in contact with the pin element 17. The rotation spindle 11 is connected to the pin element 17 via the sliding spindle 9.

(14) The pin element 17 comprises guiding means 8 for guiding a gas flow between the gas inlet channel 4 and the gas outlet channel 5 when the sealing element 7 is in the second position. The guiding means 8 extends in the longitudinal direction of the pin element 17 and is arranged to allow gas to leave the passage 4 in a radial direction of the pin element 17.

(15) The guiding means 8 comprises a longitudinally extending recess formed in an outer surface of the pin element 17. The outer surface of the pin element 17 extends between a first 24 and a second 20 axial end of the pin element 17.

(16) The pin element 17 comprises restriction means 21 at the first axial end 24 which is in contact with the sealing element 7. The restriction means 21 surrounds the pin element 17 in a circumferential direction and is tapering in an axial direction from the first axial end 24 towards the second axial end 20 in a concave manner.

(17) The valve body 3 comprises an inner threading and the rotation spindle 11 has an outer threading in engagement with the inner threading of the valve body 2. Therefore, rotation of the sliding spindle 9 and thus the rotation spindle 11 in a first direction moves the sealing element 7 from the first position to the second position via the pin element 17, and rotation of the sliding spindle 9 in a second direction allows the sealing element 7 to move from the second position to the first position by means of the biasing element 10.

(18) Both the gas inlet channel 5 and the passage 4, and gas outlet channel 6 and the passage 4 are arranged essentially perpendicular to each other. The gas inlet channel 5 and the gas outlet channel 6 are further arranged in parallel with a distance between them, where the distance is bridged by the passage 4.

(19) The following passages describes normal operation of the shut-off valve 2 and relates to FIG. 3a and FIG. 3b.

(20) Opening and closing of the shut-off valve 2 is realised through the hand wheel 1, which is joined by a nut and square plate with the sliding spindle 9. The sliding spindle 9 matches with the rotation spindle 11 through grooving and will ensure a rotational joint between the two components while only allowing axial movement upon activation of the emergency stop mechanism.

(21) When the hand wheel 1 is rotated anticlockwise, the rotation spindle 11 together with the sliding spindle 9 is rotated as well and consequently moves together with the pin element 17 in the axial direction. Subsequently, the sealing element 7 is moved into the second position via the pin element 17 such that the passage 4 between the inlet channel 5 and the outlet channel 6 is open to allow medium to pass through (FIG. 3a).

(22) When the hand wheel 18 is rotated clockwise, the rotation spindle 11 together with the sliding spindle 9 is rotated as well and consequently moves together with the pin element 17 in the opposite axial direction so that the sealing element 7 is allowed to move back into the first position by means of the biasing force from the biasing element 10 acting upon the lower spindle 13, which houses the sealing element 7. Here, in the first position, the sealing element 7 is in engagement with the valve body 2 and thus the passage 4 between the inlet channel 5 and the outlet channel 6 is closed to stop medium from passing through (FIG. 3b).

(23) The following passages describes operation of the shut-off valve 2 during an emergency and relates to FIG. 4a and FIG. 4b.

(24) When valve is in fully or partially open position (FIG. 3a or FIG. 4a), it is possible to activate emergency stop state by pushing the hand wheel 1 in the axial direction and thus immediately close the shut-off valve 2. When the hand wheel 1 is pushed, it moves the pin member 14 in axial direction accordingly. When the pin member 14 movement is so big that the recesses 16 of the pin member 14 are aligned with the through holes 22, the ball members 12 will shrink in the radial direction out of engagement with the recesses 15 of the rotation spindle 11 and into engagement with the recesses 16 of the pin member 14. As a consequence, the sliding spindle 9 will be free from engagement with the rotation spindle 11 in the axial direction. Thus, the biasing element 10 will move the lower spindle 13 and thus the sealing element 7 into the first position, thereby activating the emergency state of the shut-off valve 2. Simultaneously, the pin element 17 and the sliding spindle 9 will be moved into their idle positions since both components are connected to the sealing element 7.

(25) Once the emergency state is activated (FIG. 4b), the shut-off valve 2 stays in the closed position until the emergency stop mechanism is reset. For reset of the emergency stop mechanism it is necessary rotate the hand wheel 1 in clockwise direction. Consequently, the rotation spindle will be rotated and moved as well. When the movement of the rotation spindle 11 is so big that the recesses 15 are aligned with the ball members 12, the ball members will expand in the radial direction. Thereafter, the pin member 14 and the hand wheel 1 is moved by spring 23 into the idle position.

(26) The shut-off valve 2 is also fitted by a status indicator 25 which comprises a sliding indicator 26, an indicator guide 27 and an indicator spring 28. In addition to that, the hand wheel 1 is equipped with a window 29 which is located around outer cylindrical surface of the shut-off valve 2 and through which the status is indicated for the user.

(27) The sliding indicator 26 is rotating together with the hand wheel 1. The indicator guide 27 is not rotatable because of ribs matching grooves in the valve body 3. As the hand wheel 1 is rotated clockwise or anticlockwise, the sliding indicator 26 is moved against the window 29 of the hand wheel 1 since the axial movement of the sliding indicator 26 is driven by the indicator 27. Consequently, the colour indicated in the window 29 of the hand wheel 1 is changed in accordance with the direction of hand wheel rotation and the status of the shut off valve 2.

(28) The sliding indicator 26 is able to indicate three states of the shut-off valve 2—opened, partially opened and closed. For indication of activation of the emergency stop mechanism, there are bars on the top of the hand wheel 1 which, when pushed, moves over the sliding indicator 26 in the window 29 of the hand wheel 1. These bars stay in the window 29 until emergency stop mechanism is reset.

(29) The skilled person realises that a number of modifications of the embodiments described herein are possible without departing from the scope of the invention, which is defined in the appended claims.

(30) For instance, the hand wheel 1 may be directly connected to the sliding spindle 9 and/or to the pin member 14.

(31) The inner and the outer threading, respectively, may be a high-pitched threading.

(32) The pin element connects the sliding spindle with the sealing element. However, it should be noted that in one preferred embodiment, there is no permanent connection between the sliding spindle and the pin element or between the pin element and the sealing element.