Ventilation tube for a start-up device

Abstract

Provided is an air vent for a vibration generator that allows air to flow in or out in accordance with the pressure difference between the inside and outside of a housing, and that prevents water from entering the housing even when not in water. The air vent has a central passage (61) formed so as to extend from an inner side portion (31) to an outer side portion (32) of a vibration shaft (3); an inner side opening portion (62) formed in the outer circumferential surface of the inner side portion (31); an air intake opening portion (63) formed in the surface of the outer side portion (32); an air exhaust opening portion (64); an inner side passage (65) that communicates the central passage (61) and the inner side opening portion (62); an air intake passage (66) that communicates the central passage (61) and the air intake opening portion (63); and an air exhaust passage (67) that communicates the central passage (61) and the air exhaust opening portion (64). An air intake valve (7) that opens when negative pressure is generated in the housing is disposed in the air intake passage (66), and an air exhaust valve (8) that opens when positive pressure is generated in the housing is disposed in the air exhaust passage (67).

Description

Technical Field

[0001] This invention relates to a vent pipe for a vibration starting device installed in a vibratory compactor. Background Technology

[0002] In vibratory compactors used for compacting roadbeds, etc., models equipped with compaction discs (such as flatbed rollers or vibratory rollers) are configured such that a vibration device is installed on the compaction disc, and the vibration generated by the vibration device is transmitted to the compaction disc, thereby enabling the compaction of the roadbed, etc., on the underside of the compaction disc.

[0003] Conventional vibration starting devices typically consist of a housing, an eccentric hammer disposed within the housing, a rotating shaft (vibration starting shaft) on which the eccentric hammer is mounted or integrated with the eccentric hammer, and bearings supporting the vibration starting shaft. The vibration starting shaft comprises a portion extending inside the housing and a portion protruding outward through the housing (outer portion), and is configured such that rotational driving force is transmitted from a prime mover (internal combustion engine, electric motor, etc.) to the vibration starting shaft via a power transmission mechanism (e.g., pulleys fixed to the output shaft of the prime mover and the outer portion of the vibration starting shaft, respectively, and a V-belt wound around the pulleys), and the eccentric hammer rotates within the housing to generate vibration.

[0004] The housing contains oil for lubricating bearings and other components. Furthermore, the starting shaft, which penetrates the housing, is sealed with an oil seal to prevent lubricating oil leakage (leaking out along the circumference of the starting shaft to the outside of the housing).

[0005] Furthermore, an air passage is typically formed in the vibration device to connect the inner and outer spaces of the housing. If the housing is sealed, the oil seals sealing the vibration shaft may break or deviate from their proper installation position when a pressure difference is generated inside and outside. However, by forming an air passage that connects the inside and outside of the housing, such problems can be avoided. In addition, the air passage that connects the inside and outside of the housing to allow air to flow in and out is generally called a "vent pipe".

[0006] In the case where a vent pipe is formed in the vibrating device to connect the inside and outside of the housing, dust generated during rolling operations may enter the inner space of the housing through the vent pipe. In this case, it may damage the bearings or other moving parts. Therefore, it is considered effective to form the outer opening of the vent pipe in a location where dust is unlikely to enter or where the possibility of dust distribution is low.

[0007] For example, the outer side of the starter shaft (the part that protrudes outward through the housing) is covered by a belt cover when the pulley for the V-belt is fixed. Therefore, when an outer opening of a vent pipe is formed on the outer side of the starter shaft (more specifically, when an air passage constituting a vent pipe is formed inside the starter shaft, and one end of the passage opens on the outer side protruding outward from the housing, and the other end opens on the inner side of the housing), dust can be prevented from entering the housing from the vent pipe.

[0008] Existing technical documents

[0009] Patent documents

[0010] Patent Document 1: Japanese Patent Publication No. 56-13369 Summary of the Invention

[0011] The technical problem that the invention aims to solve

[0012] However, when an air passage forming a vent pipe is formed inside the vibrating shaft and an outer opening of the vent pipe is formed on the outer side of the vibrating shaft, there is a problem that water can easily penetrate into the housing of the vibrating device when the vibratory compactor is partially (e.g., the lower half) submerged in water.

[0013] In a typical vibratory compactor, the vibration initiator is fixed to the upper surface of the compaction disc to effectively transmit the generated vibration to the lowest part of the compaction disc. The prime mover is fixed to a support base held above the compaction disc via a vibration damping unit at a position higher than the vibration initiator. That is, when the vibratory compactor is stored outdoors in an unattended state, such as at the work site, if flooding occurs in the surrounding area due to heavy rain or sudden torrential downpours, the rising water level will, in sequence, cause the compaction disc to submerge first, followed by the vibration initiator, and then the prime mover.

[0014] While it's understood that the entire vibratory compactor needs repair if the portion below the prime mover is not submerged, if only the lower half (below the vibrating device) is submerged, the manager may not be able to detect this since the prime mover itself is functioning normally. Furthermore, when the vibrating device, whose vent pipe is formed on the vibrating shaft, is submerged, moisture can seep into the casing through the vent pipe. If the prime mover is started directly in this state to operate the vibrating device, the increased rotational load or bearing rust increases the likelihood of mechanical failure or damage.

[0015] The present invention was made in an attempt to solve the problems in the prior art, and its object is to provide a vent pipe for a vibration starter that allows air to flow in or out based on the pressure difference between the inside and outside of the housing when the starter is running, and prevents water from entering the housing when not running, even when not in water.

[0016] Technical solutions adopted to solve technical problems

[0017] The vent pipe for the vibration starting device of the present invention is formed on the vibration starting shaft, which is composed of an inner portion extending inside the housing of the vibration starting device and an outer portion protruding outward through the housing. The vent pipe for the vibration starting device is characterized by having: a central passage extending from the inner portion to the outer portion inside the vibration starting shaft; an inner opening formed on the outer peripheral surface of the inner portion of the vibration starting shaft; an intake opening formed on the surface of the outer portion of the vibration starting shaft; an exhaust opening formed on the surface of the outer portion of the vibration starting shaft; and an inner passage connecting the central passage and the inner opening. An intake passage connects the central passage and the intake opening; and an exhaust passage connects the central passage and the exhaust opening. An intake valve that opens when there is negative pressure inside the housing is disposed in the intake passage. The intake valve consists of a valve core, a valve seat disposed at a position further outward in the radial direction than the valve core, and a spring that applies force to the valve core from the central passage side toward the intake opening side. An exhaust valve that opens when there is positive pressure inside the housing is disposed in the exhaust passage. The exhaust valve consists of a valve core, a valve seat disposed at a position further inward in the radial direction than the valve core, and a spring that applies force to the valve core from the exhaust opening side toward the central passage side.

[0018] Furthermore, the ventilation pipe of the vibration device is preferably configured such that when the vibration shaft is in a non-rotating state, a negative pressure is formed inside the housing and the pressure difference between the inner and outer sides of the housing exceeds a certain value, the intake valve opens to allow air to flow into the inner side of the housing. In addition, it is preferably configured such that when a positive pressure is formed inside the housing and the pressure difference between the inner and outer sides of the housing exceeds a certain value, the exhaust valve opens to allow air to flow out to the outer side of the housing.

[0019] Furthermore, it is preferably configured such that when the starting shaft is in a rotating state, the opening pressure of the intake valve is greater than the opening pressure when the starting shaft is in a non-rotating state, and the opening pressure of the exhaust valve is less than the opening pressure when the starting shaft is in a non-rotating state, or the exhaust valve is open.

[0020] In addition, the central passage is preferably formed along the central axis of the starting shaft, and preferably, the intake opening is formed on the outer peripheral surface of the outer side of the starting shaft, and the exhaust opening is formed at the front end of the outer side of the starting shaft.

[0021] Furthermore, the vent pipe for the vibration starting device of the present invention is formed by an vibration starting shaft consisting of an inner portion extending inside the housing of the vibration starting device and an outer portion protruding outward through the housing, and a member fixed to the outer portion. The vent pipe is characterized by having: a central passage extending from the inner portion to the outer portion inside the vibration starting shaft; an inner opening formed on the outer peripheral surface of the inner portion of the vibration starting shaft; an intake opening formed on the surface of the member fixed to the outer portion of the vibration starting shaft; an exhaust opening formed on the surface of the member fixed to the outer portion of the vibration starting shaft; and an inner passage that allows the central passage to pass through... The passage is connected to the inner opening; the intake passage connects the central passage and the intake opening; and the exhaust passage connects the central passage and the exhaust opening. An intake valve that opens when there is negative pressure inside the housing is disposed in the intake passage. The intake valve consists of a valve core, a valve seat disposed at a position further outward in the radial direction than the valve core, and a spring that applies force to the valve core from the central passage side toward the intake opening side. An exhaust valve that opens when there is positive pressure inside the housing is disposed in the exhaust passage. The exhaust valve consists of a valve core, a valve seat disposed at a position further inward in the radial direction than the valve core, and a spring that applies force to the valve core from the exhaust opening side toward the central passage side.

[0022] Invention Effects

[0023] In a vibration starting device using the vent pipe of the present invention, problems such as damage to the oil seal of the vibration starting shaft can be ideally avoided. Furthermore, the intake and exhaust openings of the vent pipe of the present invention are formed on the outer side of the vibration starting shaft, and this outer side is covered by a cap, thus ideally preventing dust from entering the housing from the vent pipe.

[0024] Furthermore, in the vibration device using the vent pipe of the vibration device of the present invention, as long as the differential pressure between the inside and outside of the housing does not exceed a predetermined value, the intake valve and the exhaust valve will remain in the closed state. Therefore, even if the posture of the vibratory compactor equipped with the vibration device is changed in any direction, the problem of lubricating oil leaking from the vent pipe inside the housing can be avoided.

[0025] Furthermore, even when the vibratory compactor equipped with the vent pipe for the vibration device using the present invention is not submerged in water, water can be prevented from entering the housing by using the intake valve and exhaust valve in the closed state, thereby ideally avoiding problems such as malfunctions or damage to the vibration device caused by water intrusion. Attached Figure Description

[0026] Figure 1 This is a partial cross-sectional view of the vibration device 1 of the vent pipe 6 according to the first embodiment of the present invention.

[0027] Figure 2 yes Figure 1 An enlarged cross-sectional view of the intake valve 7 shown.

[0028] Figure 3 yes Figure 1 An enlarged sectional view of the exhaust valve 8 shown. Detailed Implementation

[0029] Hereinafter, with reference to the accompanying drawings, an embodiment of the "vent pipe for vibration starting device" of the present invention will be described. Figure 1 This is a cross-sectional view of the vibration device 1 for the vent pipe according to the first embodiment of the present invention. The vibration device 1 consists of a housing 2, a vibration shaft 3 (rotation shaft), a bearing 4 that supports the vibration shaft 3 for free rotation, and an eccentric hammer (not shown) mounted relative to the vibration shaft 3.

[0030] The starting shaft 3 consists of an inner portion 31 extending inside the housing 2 and an outer portion 32 protruding outward through the housing 2. A pulley (not shown) is fixed to the outer portion 32, and the rotational driving force is transmitted from the prime mover (internal combustion engine, electric motor, etc.) to the starting shaft 3 via a V-belt (not shown). Oil for lubricating bearings 4, etc., is stored inside the housing 2. In addition, the starting shaft 3, which penetrates the housing 2, is sealed by an oil seal 5, thereby preventing the leakage of lubricating oil.

[0031] like Figure 1 As shown, the vent 6 of the present invention is formed in the vibrating shaft 3. More specifically, inside the vibrating shaft 3, the central passage 61 constituting the vent 6 is formed to extend from the inner portion 31 side to the outer portion 32 side along the central axis of the vibrating shaft 3. Furthermore, an inner opening 62 is formed on the outer peripheral surface of the inner portion 31 of the vibrating shaft 3, and two outer openings (inhalation opening 63 and exhaust opening 64) are formed on the surface of the outer portion 32. In addition, the inhalation opening 63 is formed on the outer peripheral surface of the outer portion 32, and the exhaust opening 64 is formed at the front end of the outer portion 32.

[0032] The inner opening 62 is connected to the central passage 61 via the inner passage 65, and the intake opening 63 is connected to the central passage 61 via the intake passage 66. In addition, the exhaust opening 64 is connected to the central passage 61 via the exhaust passage 67.

[0033] An intake valve 7 is installed within the intake passage 66. For example... Figure 2 As shown, the intake valve 7 consists of a ball valve 71 (valve core), a valve seat 72, and a spring 73 that applies force to the ball valve 71 toward the valve seat 72.

[0034] Within the intake passage 66, the ball valve 71 is positioned on the central passage 61 side, which is further inward in the radial direction than the valve seat 72, while the valve seat 72 is positioned on the intake opening 63 side, which is further outward in the radial direction than the ball valve 71. Therefore, the ball valve 71 is configured to close by being pressed against the intake valve 7 from the central passage 61 side toward the intake opening 63 side by the spring 73.

[0035] When the suction valve 7 is under negative pressure inside the housing 2 and the pressure exerted on the ball valve 71 by the differential pressure between the inside and outside of the housing 2 exceeds the set opening pressure, the valve opens and the air from the outside flows into the inside of the housing 2 through the suction opening 63, the suction passage 66, the central passage 61 and the inner passage 65.

[0036] The opening pressure of the intake valve 7 when the starting shaft 3 is in a non-rotating state can be calculated based on the pressure-bearing area of ​​the ball valve 71 and the spring constant of the spring 73. Furthermore, by appropriately adjusting these values, the desired opening pressure can be achieved.

[0037] On the other hand, when the vibration device 1 is running, that is, when the vibration shaft 3 is rotating, the centrifugal force acts on the ball valve 71, causing the ball valve 71 to be located further in the radial direction than the valve seat 72. Therefore, the opening pressure of the suction valve 7 is greater than when the vibration shaft 3 is not rotating.

[0038] An exhaust valve 8 is installed in the exhaust passage 67. For example... Figure 3 As shown, the exhaust valve 8 consists of a ball valve 81 (valve core), a valve seat 82, and a spring 83 that applies force to the ball valve 81 toward the valve seat 82.

[0039] Within the exhaust passage 67, the ball valve 81 is positioned at the exhaust opening 64, which is further outward in the radial direction than the valve seat 82 (see reference). Figure 1 The valve seat 82 is positioned on the central passage 61 side, which is further in the radial direction than the ball valve 81. Therefore, it is configured such that the exhaust opening 64 (see reference 64) is accessed via the spring 83. Figure 1 The ball valve 81 of the exhaust valve 8 is pressed and closed on the side facing the central passage 61.

[0040] When the exhaust valve 8 is under positive pressure inside the housing 2 and the pressure exerted on the ball valve 81 by the differential pressure between the inside and outside of the housing 2 exceeds the set opening pressure, the air inside the housing 2 flows out from the exhaust opening 64 to the outside of the housing 2 through the inner passage 65, the central passage 61 and the exhaust passage 67.

[0041] The opening pressure of the exhaust valve 8 when the starting shaft 3 is in a non-rotating state can be calculated based on the pressure-bearing area of ​​the ball valve 81 and the spring constant of the spring 83. Furthermore, by appropriately adjusting these values, the desired opening pressure can be achieved.

[0042] On the other hand, when the starting shaft 3 is rotating, the centrifugal force acts on the ball valve 81, causing the ball valve 81 to be located further outward in the radial direction than the valve seat 82. Therefore, the opening pressure of the exhaust valve 8 is smaller than when the starting shaft 3 is not rotating, or the exhaust valve 8 is open.

[0043] As explained above, Figure 1 The vibration device 1 shown is configured such that when a differential pressure is generated inside and outside the housing 2 and its magnitude exceeds a predetermined value, the intake valve 7 or exhaust valve 8 of the vent pipe 6 opens to allow air to flow. Therefore, problems such as damage to the oil seal of the vibration shaft 3 can be ideally avoided. In addition, the outer openings of the vent pipe 6 (intake opening 63 and exhaust opening 64) are formed on the outer side 32 of the vibration shaft 3, and the outer side 32 is covered by a cover. Therefore, dust can be ideally prevented from entering the housing 2 from the vent pipe 6.

[0044] In addition, Figure 1 In the vibration device 1 shown, as long as the differential pressure between the inside and outside of the housing 2 does not exceed a predetermined value, the intake valve 7 and exhaust valve 8 of the vent pipe 6 will remain in a closed state. Therefore, even if the posture of the vibratory compactor equipped with the vibration device 1 is changed in any direction, for example, even if the machine body is tilted towards the direction where the vent pipe 6 is on the lower side, the problem of lubricating oil leaking from the vent pipe 6 inside the housing can be avoided.

[0045] In addition, even when equipped with Figure 1Even when the vibratory compactor of the vibration device 1 shown is not submerged in water, water intrusion into the housing 2 can be prevented by the closed air intake valve 7 and air exhaust valve 8. This ideally avoids problems such as malfunctions or damage to the vibration device 1 caused by water intrusion. When the vibration device 1 is not operating, even when it is not submerged in water and the pressure inside the housing 2 drops to the level where the air intake valve 7 is open, water intrusion will not occur. This is because water, as a fluid, is more difficult to pass through valves than air. Therefore, as long as the temperature inside the housing 2 does not change extremely rapidly and drastically, for example, except when the vibratory compactor is not submerged in water and the temperature rises to saturation during prolonged operation of the vibration device 1, water intrusion can be prevented.

[0046] In addition, in this embodiment, such as Figure 1 As shown, a portion of the intake passage 66, equipped with the intake valve 7, and a portion of the exhaust passage 67, equipped with the exhaust valve 8, are configured to be connected in series along the radial direction of the starting shaft 3 (i.e., configured to be positioned at 180° to the central axis of the starting shaft 3). However, it is also possible to form a portion of the exhaust passage 67 equipped with the exhaust valve 8 at a position offset from the direction of the starting shaft 3 in either the circumferential direction or the direction of the central axis (for example, a position moved 90° around the central axis of the starting shaft 3, or a position moved towards the exhaust opening 64). In this case, during assembly, a connecting hole for guiding the ball valve 71 and spring 73 of the intake valve 7 into the intake passage 66 can be formed. Figure 1 The configuration includes the location of the exhaust valve 8.

[0047] Furthermore, in the above embodiments, such as Figure 1 As shown, the intake opening 63 and the exhaust opening 64 constituting the vent pipe 6 are formed on the surface of the outer side 32 of the vibrating shaft 3. However, it is also possible that the intake opening and the exhaust opening are respectively on the surface of the "component fixed to the outer side" (a component fixed relative to the outer side 32 and rotating integrally with the outer side 32, such as a pulley or collar (not shown)). An intake passage is formed inside the "component fixed to the outer side" and inside the outer side 32 to connect the central passage 61 and the above-mentioned intake opening, and an exhaust passage is formed to connect the central passage 61 and the above-mentioned exhaust opening. An intake valve is disposed inside the intake passage (inside the "component fixed to the outer side" and / or inside the outer side 32), and an exhaust valve is disposed inside the exhaust passage (inside the "component fixed to the outer side" and / or inside the outer side 32).

[0048] (Symbol Explanation)

[0049] 1: Vibration starting device;

[0050] 2: Outer shell;

[0051] 3: Vibration shaft;

[0052] 31: Inner side;

[0053] 32: Outer side;

[0054] 4: Bearings;

[0055] 5: Oil seals;

[0056] 6: Ventilation tube;

[0057] 61: Central passageway;

[0058] 62: Inner opening;

[0059] 63: Inhalation opening;

[0060] 64: Exhaust opening;

[0061] 65: Medial pathway;

[0062] 66: Inspiratory pathway;

[0063] 67: Exhaust passage;

[0064] 7: Intake valve;

[0065] 71: Ball valve;

[0066] 72: Valve seat;

[0067] 73: Spring;

[0068] 8: Exhaust valve;

[0069] 81: Ball valve;

[0070] 82: Valve seat;

[0071] 83: Spring.

Claims

1. A breather pipe for a starting device, The breather pipe for a starting device is formed in a starting shaft composed of an inner side portion extending inside a housing of a starting device and an outer side portion protruding outside the housing, characterized by The breather pipe for a starting device has: a central passage formed to extend inside the starting shaft from the inner side portion to the outer side portion; an inner side opening portion formed in an outer peripheral surface of the inner side portion; an air intake opening portion formed in a surface of the outer side portion; an air exhaust opening portion formed in a surface of the outer side portion; an inner side passage communicating the central passage and the inner side opening portion; an air intake passage communicating the central passage and the air intake opening portion; and an air exhaust passage communicating the central passage and the air exhaust opening portion, an air intake valve opening when negative pressure is created inside the housing is disposed in the air intake passage, the air intake valve being composed of a valve core, a valve seat disposed at a position more radially outward than the valve core, and a spring applying force to the valve core from the central passage side toward the air intake opening portion side, an air exhaust valve opening when positive pressure is created inside the housing is disposed in the air exhaust passage, the air exhaust valve being composed of a valve core, a valve seat disposed at a position more radially inward than the valve core, and a spring applying force to the valve core from the air exhaust opening portion side toward the central passage side.

2. The breather pipe for a starting device according to claim 1, characterized in that when the starting shaft is in a non-rotating state, the air intake valve opens to allow air to flow into the inside of the housing when the difference in pressure between the inside and the outside of the housing exceeds a certain value while negative pressure is created inside the housing.

3. The breather pipe for a starting device according to claim 1, characterized in that when the starting shaft is in a non-rotating state, the air exhaust valve opens to allow air to flow out to the outside of the housing when the difference in pressure between the inside and the outside of the housing exceeds a certain value while positive pressure is created inside the housing.

4. The breather pipe for a starting device according to claim 1, characterized in that the air intake valve is configured to have a larger opening pressure when the starting shaft is in a rotating state than when the starting shaft is in a non-rotating state.

5. The breather pipe for a starting device according to claim 1, characterized in that the air exhaust valve is configured to have a smaller opening pressure when the starting shaft is in a rotating state than when the starting shaft is in a non-rotating state, or the air exhaust valve opens.

6. The breather pipe for a starting device according to claim 1, characterized in that the central passage is formed along a central axis of the starting shaft.

7. The breather pipe for a starting device according to claim 1, characterized in that the air intake opening portion is formed in an outer peripheral surface of the outer side portion of the starting shaft.

8. The breather pipe for a starting device according to claim 1, characterized in that the air exhaust opening portion is formed in a front end portion of the outer side portion of the starting shaft.

9. A breather pipe for a starting device formed in a starting shaft composed of an inner side portion extending inside a housing of a starting device and an outer side portion protruding outside the housing and a member fixed to the outer side portion, characterized by The oscillation starting device has: a central passage formed inside the oscillation shaft from the inner side portion to the outer side portion; an inner side opening portion formed on the outer peripheral surface of the inner side portion of the oscillation shaft; an air intake opening portion formed on the surface of a member fixed to the outer side portion of the oscillation shaft; an air exhaust opening portion formed on the surface of a member fixed to the outer side portion of the oscillation shaft; an inner side passage that communicates the central passage and the inner side opening portion; an air intake passage that communicates the central passage and the air intake opening portion; and an air exhaust passage that communicates the central passage and the air exhaust opening portion, an air intake valve that opens when negative pressure is created inside the housing is disposed in the air intake passage, the air intake valve is composed of a valve core, a valve seat disposed at a position more radially outward than the valve core, and a spring that exerts force on the valve core from the central passage side toward the air intake opening portion side, an air exhaust valve that opens when positive pressure is created inside the housing is disposed in the air exhaust passage, the air exhaust valve is composed of a valve core, a valve seat disposed at a position more radially inward than the valve core, and a spring that exerts force on the valve core from the air exhaust opening portion side toward the central passage side.

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