JP6672985B2 - In-vehicle optical sensor cleaning device - Google Patents

Description

The present invention relates to a vehicle optical sensor cleaning equipment.

  Patent Literature 1 below discloses an on-vehicle optical sensor cleaning apparatus for cleaning a lens, a cover, and the like by spraying a cleaning liquid onto a lens, a cover, and the like of an on-vehicle optical sensor such as a camera. This in-vehicle optical sensor cleaning device has an in-vehicle optical sensor and a camera washer nozzle arranged at the rear of the vehicle, and the camera washer nozzle is connected to a washer pump arranged at the front of the vehicle by a hose. I have.

JP 2012-236585 A

  By the way, in the above-mentioned in-vehicle optical sensor cleaning device, when supplying the cleaning liquid to the camera washer nozzle, the operating voltage of the washer pump may vary. In addition, variations in the temperature, concentration, and viscosity of the cleaning liquid may occur due to fluctuations in the use environment temperature. These variations may cause variations in the supply amount of the cleaning liquid to the camera washer nozzle. Therefore, the supply amount of the cleaning liquid to the camera washer nozzle is set in consideration of the variation in the supply amount of the cleaning liquid. In other words, the supply amount is set such that a sufficient amount of the cleaning liquid is supplied to the camera washer nozzle even if the supply amount of the cleaning liquid varies. As a result, there is a problem that the set supply amount of the cleaning liquid to the camera washer nozzle increases and the consumption amount of the cleaning liquid in the washer tank increases.

The present invention is, in consideration of the above circumstances, and an object thereof is to provide a vehicle optical sensor cleaning equipment which can suppress the greater the consumption of the cleaning liquid in the washer tank.

  The on-vehicle optical sensor cleaning device of the present disclosure is provided with an optical sensor cleaning nozzle having an injection port for injecting a cleaning liquid in a washer tank pressure-fed by a washer pump to an on-vehicle optical sensor, and provided between the washer pump and the injection port. A constant-volume pump for supplying a constant-volume washing liquid to the injection port when activated.

  According to the on-vehicle optical sensor cleaning device having the above-described configuration, the cleaning liquid in the washer tank, which is pressure-fed by the washer pump, is jetted from the jet of the optical sensor cleaning nozzle to the on-vehicle optical sensor. Thereby, the on-vehicle optical sensor can be cleaned.

  Here, a constant volume pump is provided between the washer pump and the ejection port of the optical sensor cleaning nozzle. Then, by operating the constant volume pump, a constant volume of the cleaning liquid is supplied to the ejection port of the optical sensor cleaning nozzle. Therefore, even if the operating voltage of the washer pump fluctuates or the temperature, concentration, and viscosity of the cleaning liquid fluctuate due to fluctuations in the operating environment temperature, a constant volume of the cleaning liquid is supplied to the injection port of the optical sensor cleaning nozzle. Can be supplied by Thus, it is possible to suppress the consumption of the cleaning liquid in the washer tank from increasing.

  Further, in the on-vehicle optical sensor cleaning device of the present disclosure, the constant displacement pump is disposed at a position closer to the optical sensor cleaning nozzle than the washer pump.

  According to the on-vehicle optical sensor cleaning device having the above configuration, it is possible to suppress a variation in the amount of the cleaning liquid supplied to the optical sensor cleaning nozzle due to air entering the cleaning liquid. That is, each of the optical sensor cleaning nozzle, the constant volume pump, and the washer pump is usually connected by a hose or the like. In this case, there is a possibility that air passing through the hose may enter the cleaning liquid. Here, the constant volume pump is arranged at a position closer to the optical sensor cleaning nozzle than the washer pump. Therefore, the length of the hose connecting between the optical sensor cleaning nozzle and the constant volume pump can be set shorter than the length of the hose connecting between the constant volume pump and the washer pump. Therefore, it is possible to prevent air from entering the cleaning liquid between the constant volume pump and the optical sensor cleaning nozzle. Therefore, it is possible to suppress a variation in the amount of the cleaning liquid supplied to the optical sensor cleaning nozzle due to air entering the cleaning liquid. As a result, the constant volume pump can satisfactorily supply a constant volume of the cleaning liquid to the ejection port of the optical sensor cleaning nozzle.

  Further, in the on-vehicle optical sensor cleaning device of the present disclosure, a gas-liquid separation device is provided between the washer pump and the optical sensor cleaning nozzle, and between the gas-liquid separation device and the optical sensor cleaning nozzle. Is provided with the constant volume pump, and the gas-liquid separation device separates the cleaning liquid pressure-fed from the washer pump from a gas contained in the cleaning liquid, and separates the separated cleaning liquid into the constant pressure. Discharge to capacity pump.

  According to the on-vehicle optical sensor cleaning device having the above configuration, since the gas-liquid separation device is provided on the upstream side of the constant volume pump, the cleaning liquid in a state where the gas is separated can be supplied to the constant volume pump. . Thus, the variation in the amount of the cleaning liquid supplied to the constant volume pump can be suppressed, and the variation in the amount of the cleaning liquid supplied to the optical sensor cleaning nozzle can be suppressed.

  Further, in the on-vehicle optical sensor cleaning device of the present disclosure, the constant-volume pump includes a cylinder having a housing portion having a bottomed cylindrical shape, and is disposed inside the housing portion, and a tip portion in the axial direction of the housing portion is provided. A piston that opposes a bottom wall of the housing, and a movement mechanism that operates to reciprocate the piston in the axial direction of the housing. The space between the bottom wall of the section and the tip of the piston is a pump chamber.

  According to the on-vehicle optical sensor cleaning device having the above configuration, the cleaning liquid in the pump chamber is pressure-fed to the optical sensor cleaning nozzle side by the reciprocating movement of the piston in the axial direction of the housing. This makes it possible to discharge the cleaning liquid from the pump chamber to a high pressure and supply the cleaning liquid to the optical sensor cleaning nozzle side.

  Further, in the vehicle-mounted optical sensor cleaning apparatus according to the present disclosure, the constant volume pump is provided in the storage section, and an inlet configured to allow a cleaning liquid from the washer pump to flow into the pump chamber, and provided in the storage section. A first check valve that allows the flow of the cleaning liquid from the inlet to the pump chamber when the piston moves forward, and suppresses the flow of the cleaning liquid from the pump chamber to the inlet when the piston moves backward; It has.

  According to the on-vehicle optical sensor cleaning device having the above configuration, the cleaning liquid from the washer pump flows into the pump chamber when the piston moves forward, and the backflow of the cleaning liquid in the pump chamber to the washer pump side is suppressed when the piston moves backward. be able to.

  In addition, in the vehicle-mounted optical sensor cleaning apparatus according to the present disclosure, the constant volume pump is provided in the storage unit, and an outlet configured to allow a cleaning liquid in the pump chamber to flow to the optical sensor cleaning nozzle side; The piston and the pump chamber are prevented from communicating with each other when the piston moves forward, and the outlet and the pump chamber are communicated with each other when the piston moves backward. A second check valve that allows the flow of the cleaning liquid to the second check valve.

  According to the on-vehicle optical sensor cleaning device having the above-described configuration, when the piston moves forward, air is suppressed from entering the pump chamber from the outlet, and when the piston returns, the cleaning liquid flows out of the pump chamber to the outlet to return to the optical sensor. It can be discharged to the cleaning nozzle side.

  Further, in the on-vehicle optical sensor cleaning device of the present disclosure, when the moving mechanism is not in operation, the distal end of the piston is in contact with the bottom wall of the housing.

  According to the in-vehicle optical sensor cleaning device having the above-described configuration, when the moving mechanism is not in operation, the distal end of the piston is in contact with the bottom wall of the housing. Can be set smaller. That is, the amount of the cleaning liquid in the pump chamber when the moving mechanism is not operated can be reduced. Thereby, it is possible to prevent the cleaning liquid from leaking from the ejection port of the optical sensor cleaning nozzle. That is, if the amount of the cleaning liquid in the pump chamber is large in the inoperative state of the moving mechanism, for example, when the constant-volume pump is exposed to a high temperature, the cleaning liquid thermally expands, and the cleaning liquid in the pump chamber becomes an optical sensor. There is a risk of leaking to the cleaning nozzle side. In this case, there is a possibility that the cleaning liquid leaks out of the ejection port of the optical sensor cleaning nozzle. On the other hand, in the vehicle-mounted optical sensor cleaning device having the above-described configuration, as described above, the amount of the cleaning liquid in the pump chamber when the moving mechanism is not operated can be reduced. Therefore, for example, even if the constant-volume pump is exposed to high temperatures, the cleaning liquid in the pump chamber can be prevented from leaking to the optical sensor cleaning nozzle, and the cleaning liquid can be prevented from leaking from the injection port of the optical sensor cleaning nozzle. can do.

  In the vehicle-mounted optical sensor cleaning device according to the present disclosure, a protrusion protruding toward the pump chamber is provided on at least one of the distal end of the piston and the bottom wall of the housing.

  According to the on-vehicle optical sensor cleaning device configured as described above, the piston can be satisfactorily reciprocated when the moving mechanism operates. That is, if the projection is omitted, the entire distal end of the piston and the entire bottom wall of the housing come into contact with each other. The tip of the piston sticks to the bottom wall of the housing due to the cleaning liquid remaining in the pump chamber, and the piston may not be able to reciprocate satisfactorily. On the other hand, a projection protruding toward the pump chamber is provided on at least one of the distal end of the piston and the bottom wall of the housing. For this reason, the contact area between the tip of the piston and the bottom wall of the housing can be reduced. This suppresses the tip of the piston from sticking to the bottom wall of the housing. Therefore, the piston can be satisfactorily reciprocated when the moving mechanism operates.

  Further, the on-vehicle optical sensor cleaning nozzle of the present disclosure is provided with an injection port for injecting the cleaning liquid in the washer tank pumped by the washer pump to the on-vehicle optical sensor, and is provided on the upstream side of the injection port and operates to have a constant volume. A constant volume pump unit for supplying the cleaning liquid to the injection port.

  According to the on-vehicle optical sensor cleaning nozzle having the above-described configuration, the cleaning liquid in the washer tank that has been pressure-fed by the washer pump is jetted from the injection port of the on-vehicle optical sensor cleaning nozzle to the on-vehicle optical sensor. Thereby, the on-vehicle optical sensor can be cleaned.

  Here, a constant displacement pump section is provided on the upstream side of the injection port. Then, by operating the constant volume pump unit, a constant volume of the cleaning liquid is supplied to the injection port. For this reason, even if the operating voltage of the washer pump fluctuates or the temperature, concentration, and viscosity of the cleaning liquid fluctuate due to fluctuations in the use environment temperature, the constant volume pump unit supplies a constant volume of the cleaning liquid to the injection port. be able to. Thus, it is possible to suppress the consumption of the cleaning liquid in the washer tank from increasing.

FIG. 1 is a configuration diagram showing the overall configuration of the on-vehicle optical sensor cleaning device according to the present embodiment. FIG. 2 is a perspective view showing the gas-liquid separation device shown in FIG. FIG. 3 is an exploded perspective view showing the gas-liquid separation device shown in FIG. FIG. 4 is a plan view showing a state where a liquid level sensor is attached to the tank of the gas-liquid separation device shown in FIG. FIG. 5 is a vertical cross-sectional view (cross-sectional view along line 5-5 in FIG. 2) of the gas-liquid separation device shown in FIG. FIG. 6 is a longitudinal sectional view (a sectional view taken along line 6-6 in FIG. 2) of the gas-liquid separation device shown in FIG. 2 as viewed from a first direction. FIG. 7 is a perspective view showing the constant displacement pump shown in FIG. FIG. 8 is an exploded perspective view showing the constant displacement pump shown in FIG. 9 is a longitudinal sectional view (a sectional view along line 9-9 in FIG. 7) of the constant displacement pump shown in FIG. 7 as viewed from the second direction. FIG. 10 is a perspective view showing the inside of the piston accommodating portion in the cylinder shown in FIG. FIG. 11 is a longitudinal sectional view showing the optical sensor cleaning nozzle shown in FIG. FIG. 12 is an exploded perspective view showing a main part of a modification of the constant displacement pump shown in FIG. FIG. 13 is a longitudinal sectional view showing the entire constant displacement pump shown in FIG. 12 as viewed from a second direction. FIG. 14 is a longitudinal sectional view showing the on-vehicle optical sensor cleaning nozzle according to the present embodiment.

  Hereinafter, a vehicle-mounted optical sensor cleaning device 10 according to the present embodiment will be described with reference to the drawings. As shown in FIG. 1, the on-vehicle optical sensor cleaning device 10 includes a washer tank 12, a gas-liquid separation device 30, a constant displacement pump 80, and an optical device for cleaning the on-vehicle camera 16 as an “on-vehicle optical sensor”. And a sensor cleaning nozzle 150. Further, the on-vehicle optical sensor cleaning device 10 has a control unit 20 for controlling the operation of the on-vehicle optical sensor cleaning device 10. Hereinafter, first, the overall configuration of the on-vehicle optical sensor cleaning device 10 will be described, and then the gas-liquid separation device 30, the constant volume pump 80, and the optical sensor cleaning nozzle 150 will be described.

<Overall configuration of in-vehicle optical sensor cleaning device>
The washer tank 12 is provided in an engine room (power unit room) arranged in a front portion of a vehicle (not shown), and a washing liquid (liquid) is sealed in the washer tank 12. A washer pump 14 is provided in the washer tank 12, and one end of a first hose H1 is connected to the washer pump 14. Further, the control unit 20 is electrically connected to the washer pump 14, and the washer pump 14 is operated under the control of the control unit 20. Then, when the washing switch (not shown) of the vehicle is turned on, the washer pump 14 is operated, and the washing liquid is pumped through the first hose H1, and the gas-liquid separator 30 and the constant volume pump 80, which will be described later. It is configured to be supplied to

  The gas-liquid separation device 30 and the constant displacement pump 80 are provided on a back door (not shown) arranged at the rear of the vehicle. The other end of the first hose H1 is connected to the gas-liquid separator 30, and one end of the second hose H2 is connected. Further, the other end of the second hose H2 is connected to the constant displacement pump 80, and one end of the third hose H3 is connected thereto. Then, the cleaning liquid (liquid) that has been pressure-fed in the first hose H1 from the washer pump 14 flows into the gas-liquid separator 30 and is supplied to the constant volume pump 80 via the gas-liquid separator 30. Has become. Further, the constant displacement pump 80 is electrically connected to the control unit 20, and is configured to operate the constant displacement pump 80 under the control of the control unit 20.

  The on-vehicle camera 16 is provided, for example, at the center in the vehicle width direction above the back door of the vehicle. The vehicle-mounted camera 16 is configured to be able to photograph the rear side of the vehicle. The optical sensor cleaning nozzle 150 is arranged close to the vehicle-mounted camera 16 and fixed to the vehicle-mounted camera 16. The other end of the third hose H3 is connected to the optical sensor cleaning nozzle 150. The air pump 18 is connected to the optical sensor cleaning nozzle 150 via a fourth hose H4. The air pump 18 is electrically connected to the control unit 20. The air pump 18 operates under the control of the control unit 20 to supply high-pressure air (air) to the optical sensor cleaning nozzle 150. By operating the constant volume pump 80 and the air pump 18, the cleaning liquid mixed with air is jetted from the optical sensor cleaning nozzle 150 toward the lens of the vehicle-mounted camera 16 to clean the lens. I have. Further, the on-vehicle optical sensor cleaning device 10 has a check valve 22 in front (upstream side) of the gas-liquid separation device 30 to prevent the cleaning liquid in the gas-liquid separation device 30 from flowing to the washer pump 14. It is configured to be suppressed by the stop valve 22.

  As described above, the constant displacement pump 80 and the optical sensor cleaning nozzle 150 are provided on the back door of the vehicle, and the washer pump 14 is provided in the engine room at the front of the vehicle. Therefore, in the in-vehicle optical sensor cleaning device 10, the constant volume pump 80 is disposed at a position closer to the optical sensor cleaning nozzle 150 than the washer pump 14, and the length of the third hose H3 is equal to that of the first hose H1 and the third hose H1. The length is set significantly shorter than the total length of the two hoses H2.

<About gas-liquid separator>
The gas-liquid separation device 30 will be described with reference to FIGS. 2 to 6, an arrow A1 indicates an upper side of the gas-liquid separator 30, and an arrow B1 indicates a lower side of the gas-liquid separator 30. The vertical direction of the gas-liquid separation device 30 and the vehicle vertical direction of the vehicle match. 2 to 6, a first direction orthogonal to the vertical direction is indicated by an arrow C1 and an arrow D1, and in FIGS. 2 to 6, a second direction orthogonal to the vertical direction and the first direction is an arrow E1 and an arrow. This is indicated by F1. In the present embodiment, when the back door of the vehicle is closed, one side in the second direction (the arrow E1 side in FIGS. 2 to 6) coincides with the front side of the vehicle (in other words, the inside of the vehicle body). The other side of the direction (the arrow F1 side in FIGS. 2 to 6) coincides with the rear side of the vehicle (in other words, the outside of the vehicle body). Also, one side in the first direction (the arrow C1 side in FIGS. 2 to 6) coincides with the vehicle right side, and the other side in the first direction (the arrow D1 side in FIGS. 2 to 6) coincides with the vehicle left side.

  As shown in FIG. 2, the gas-liquid separation device 30 is formed in a substantially columnar shape extending vertically as a whole. The gas-liquid separation device 30 includes a tank 32, a discharge mechanism 60, and a liquid level sensor 70 that detects a liquid level of the cleaning liquid in the tank 32. Hereinafter, a specific description will be given.

(About tank 32)
As shown in FIGS. 3 to 6, the tank 32 is formed in a substantially bottomed cylindrical shape opened upward. A tank inlet 34 is formed integrally with the upper end of the side wall of the tank 32. The tank inlet 34 is formed in a substantially cylindrical shape, and is radially outside the tank 32 from the side wall of the tank 32 (specifically, (In one direction). The other end of the first hose H1 is connected to the tank inlet 34. Thus, the cleaning liquid pumped through the first hose H1 flows into (injects) into the tank 32.

  At the center of the bottom wall of the tank 32, a tank outlet 36 (in a broad sense, an element grasped as an "outflow portion") is integrally formed, and the tank outlet 36 is formed in a substantially cylindrical shape. And protrudes downward from the bottom wall of the tank 32. One end of the second hose H2 described above is connected to the tank outlet 36. Thus, the cleaning liquid in the tank 32 is pressure-fed in the second hose H2 and supplied to the constant volume pump 80.

  As shown in FIG. 4, inside the tank 32, at a position radially outward with respect to the tank outlet 36 (specifically, at a position between the tank outlet 36 and the tank inlet 34 in plan view), The wall 38 is formed integrally. The first wall portion 38 projects upward from the bottom wall of the tank 32 with the substantially first direction being the plate thickness direction, and is curved along the circumferential direction of the tank 32 in plan view. Then, in the radial direction of the tank 32 (specifically, the projecting direction of the tank inlet 34), the upper end of the first wall portion 38 and the tank inlet 34 are arranged to face each other. Thus, when the cleaning liquid flows (injects) from the tank inlet 34 into the tank 32, the cleaning liquid hits the first wall portion 38, and a liquid level sensor 70 described below is configured not to be directly wetted by the cleaning liquid.

  Further, inside the tank 32, a first connection rib 40A for connecting the first wall portion 38, the side wall of the tank 32, and the bottom wall of the tank 32 is integrally formed. The first connection rib 40A is arranged with the second direction as the plate thickness direction, extends along the radial direction of the tank 32 in plan view, and is arranged below the tank inlet 34. Further, inside the tank 32, a second connection rib 40B that connects the first wall portion 38 and the bottom wall of the tank 32 is integrally formed at a position between the tank outlet 36 and the first wall portion 38. ing. The second connecting ribs 40B are arranged with the second direction as the plate thickness direction, and extend along the radial direction of the tank 32 in plan view. Thus, the first wall portion 38 to which the cleaning liquid is applied is reinforced by the first connection rib 40A and the second connection rib 40B. Further, similarly to the second wall portions 42A, 42B, 42C and the third wall portion 44 described later, the first connection rib 40A and the second connection rib 40B also suppress the fluctuation of the liquid level of the cleaning liquid in the tank 32. It has a configuration.

  Further, a plurality of (three in this embodiment) second wall portions 42A, 42B, and 42C that connect the side wall and the bottom wall of the tank 32 are integrally provided inside the tank 32. The second wall portions 42A to 42C extend radially in the radial direction of the tank 32 from the center of the bottom wall of the tank 32 in a plan view, and at regular intervals (every 90 °) in the circumferential direction of the tank 32. ). Specifically, in plan view, the second wall portions 42A and 42C extend along the second direction, and the second wall portion 42B extends along the first direction. As a result, the second wall portions 42A to 42C are disposed on the opposite side (the other side in the first direction) to the tank inlet 34 with respect to the first wall portion 38, and the inside of the tank 32 becomes the second wall portion 42A. The tank 32 is partitioned in the circumferential direction by -42C. The height of the second wall portions 42 and 42C is set to be substantially the same as the height of the first wall portion 38, and the second wall portion 42B is disposed below the tank inlet 34.

  Further, inside the tank 32, a pair of third wall portions 44 connecting the side wall and the bottom wall of the tank 32 are integrally provided. The pair of third wall portions 44 has a plate thickness direction as a second direction so as to connect the side wall and the bottom wall of the tank 32 at one side and the other side of the second wall portion 42B in the second direction. It protrudes upward from the bottom wall of the tank 32. The height of the third wall portion 44 is set to be substantially the same as the height of the first wall portion 38, and the position of the third wall portion 44 in the second direction is the same as the position of the groove portion 50 described later. Is set to

  Further, a pair of ribs 44A is integrally formed at the tip of the third wall portion 44 as viewed from above. The ribs 44A extend from the third wall portion 44 to one side and the other side in the second direction. Therefore, when viewed from above, the tip of the third wall portion 44 is formed in a cross shape.

  Further, a cylindrical wall portion 46 is provided in the tank 32 at a substantially central portion. The cylindrical wall portion 46 is erected substantially at the center of the bottom wall of the tank 32 and is concentric with the flow path of the tank outlet 36 outside the flow path inside the tank outlet 36 in the radial direction. It is formed in a substantially cylindrical shape. In addition, three slits 46A extending in the vertical direction are formed in the cylindrical wall portion 46, and the slits 46A are arranged at predetermined intervals in the circumferential direction of the cylindrical wall portion 46. . Thus, the cylindrical wall portion 46 is divided in the circumferential direction by the slit 46A, and the inside and the outside of the cylindrical wall portion 46 are communicated by the slit 46A. The height of the cylindrical wall 46 is set to be substantially the same as the height of the first wall 38. Further, an outer peripheral portion at an upper portion of the cylindrical wall portion 46 is cut out in a stepped shape in a longitudinal sectional view. That is, the thickness of the upper portion of the cylindrical wall portion 46 is set to be smaller than the thickness of the lower portion of the cylindrical wall portion 46.

  Further, a pair of ribs 48A and 48B extending to one side and the other side in the second direction are formed on the outer peripheral portion of the cylindrical wall portion 46, respectively. One rib 48A is spaced apart from the second wall 42A toward the other side in the second direction, and the other rib 48B is spaced apart from the second wall 42C toward the other side in the second direction. It is arranged. Thus, a groove 50 is formed between the rib 48A (48B) and the second wall 42A (42B). The third wall portion 44 and the groove portion 50 are arranged so as to overlap in the first direction.

  Further, as shown in FIGS. 3 and 5, a liquid level sensor 70 described later is attached to the outer peripheral surface of the side wall of the tank 32 at a position opposite to the tank inlet 34 (the other side in the first direction). Sensor mounting part 52 is formed integrally. The sensor mounting portion 52 is formed in a substantially rectangular parallelepiped shape having the second direction as a longitudinal direction, and protrudes from the tank 32 to the other side in the first direction. In addition, an insertion hole 52A (see FIGS. 3 and 5) penetrated in the first direction is formed at a central portion in the longitudinal direction of the sensor mounting portion 52. The insertion hole 52A is formed in a substantially rectangular shape with the second direction as a longitudinal direction, and the vertical position of the insertion hole 52A is set to a position substantially coincident with the vertical position of the tank inlet 34. In addition, concave portions 52B (see FIGS. 3 and 4) that are open to the other side in the first direction are formed at both ends in the longitudinal direction of the sensor mounting portion 52.

  As shown in FIGS. 3, 5, and 6, a vehicle attachment portion for attaching the gas-liquid separation device 30 to a vehicle (back door) is provided on the outer peripheral portion of the tank 32 at one side in the second direction. 54 are formed integrally. The vehicle mounting portion 54 is formed in a substantially C-shape that is open to one side in the second direction when viewed from above. An engagement protrusion 56 (see FIGS. 4 and 6) protruding outward in the radial direction of the tank 32 is formed integrally with the outer periphery of the tank 32 at the position of the vehicle mounting portion 54.

  A plate-like mounting plate 58 for mounting the gas-liquid separator 30 to the back door is fitted into the vehicle mounting portion 54. A substantially rectangular engaging hole 58A (see FIG. 3) is formed through the mounting plate 58. When the mounting plate 58 is fitted into the vehicle mounting portion 54, the engaging protrusion 56 of the tank 32 is disposed in the engaging hole 58A, and the engaging protrusion 56 and the engaging hole 58A are engaged in the vertical direction. Have been combined. Thus, the upward movement of the mounting plate 58 is restricted.

(About the discharge mechanism 60)
As shown in FIGS. 3 and 6, the discharge mechanism 60 is configured to include a lid 62 that closes the opening of the tank 32, and a gas discharge outlet 64 formed integrally with the lid 62. ing. The lid portion 62 is configured to include a substantially disk-shaped lid body portion 62A whose vertical direction is a plate thickness direction, and a flange portion 62B extending downward from the outer peripheral portion of the lid body portion 62A. I have. The flange 62B is formed over the entire circumference of the lid body 62A, and the upper end of the tank 32 is fitted inside the flange 62B. The flange 62B is fixed to the upper end of the tank 32 by welding or the like. As a result, the opening of the tank 32 is closed by the lid 62.

  The gas outlet 64 is formed integrally with the lid 62 on the other side in the second direction. The gas discharge outlet 64 is formed in a substantially cylindrical shape, protrudes upward from the lid portion 62, and is bent toward the other side in the second direction (that is, the vehicle rear side). The inside of the gas discharge outlet 64 is a gas discharge passage 64A, and the inside and the outside of the tank 32 are communicated with each other by the gas discharge passage 64A. Thus, the gas separated inside the tank 32 is discharged from the gas discharge passage 64A to the outside of the tank 32.

(About the liquid level sensor 70)
As shown in FIGS. 3 to 6, the liquid level sensor 70 includes a sensor main body 72 and a pair of electrodes 74A and 74B.

  The sensor main body 72 is made of resin and is bent in a substantially inverted L-shape in a side view. Further, a pair of electrode holding portions 72A are integrally formed at one longitudinal end of the sensor main body 72. A sensor-side flange 72B extending outward in the width direction (second direction) is integrally formed at a middle portion in the longitudinal direction of the sensor main body 72, and both ends of the sensor-side flange 72B in the width direction (second direction). Has a fixing hole 72C penetrated in the first direction.

  Then, with the sensor main body 72 inserted into the insertion hole 52A of the sensor mounting portion 52 of the tank 32, the screw S1 is inserted into the fixing hole 72C, and the screw S1 is inserted into the concave portion 52B of the sensor mounting portion 52. The sensor main body 72 is fixed to the tank 32 by being screwed. Accordingly, the liquid level sensor 70 is disposed on the other side in the first direction (outside the vehicle body) with respect to the tank outlet 36. When the sensor main body 72 is fixed to the tank 32, a spacer 76 is interposed between the sensor side flange 72B and the sensor mounting portion 52 of the tank 32, and the electrode holding portion 72A is located inside the tank 32. Are located in The other end in the longitudinal direction of the sensor main body 72 is a connector 72D that is bent downward and opened downward.

  The electrodes 74A and 74B are bent in a substantially inverted L-shape in a side view. Then, a portion on one side in the longitudinal direction of the electrodes 74A and 74B is formed integrally with the electrode holding portion 72A, and one ends of the electrodes 74A and 74B protrude from the electrode holding portion 72A. That is, the tips of the electrodes 74A and 74B are arranged inside the tank 32. Further, a portion on one side in the longitudinal direction of the electrodes 74A and 74B is disposed inside the connector portion 72D. The electrodes 74A and 74B are connected to a connector (not shown) inserted into the connector 72D. When the electrodes 74A and 74B are connected to the connector, one electrode 74A is grounded to the vehicle and the other electrode 74B is connected to the power supply of the vehicle. Further, the control unit 20 is electrically connected to the liquid level sensor 70, and based on a detection signal from the liquid level sensor 70, the control unit 20 controls the liquid level of the cleaning liquid in the tank 32 to a predetermined height or more. Is determined.

  Specifically, the control unit 20 measures the voltage at both ends of the resistor provided on the lead wire of the connector connected to the electrode 74A, and determines whether the voltage is higher than a predetermined voltage. The level of the cleaning liquid is determined. That is, when the liquid level of the cleaning liquid in the tank 32 is higher than the electrodes 74A and 74B, the cleaning liquid flows between the pair of electrodes 74A and 74B, and a current flows through the resistor. For this reason, the control unit 20 detects that the voltage across the resistor is higher than the predetermined voltage. Thus, the control unit 20 determines that the liquid level of the cleaning liquid in the tank 32 is equal to or higher than the predetermined height. On the other hand, when the liquid level of the cleaning liquid in the tank 32 is lower than the electrodes 74A and 74B, no current flows between the pair of electrodes 74A and 74B. For this reason, the control unit 20 detects that the voltage across the resistor is equal to or lower than the predetermined voltage. Thus, the control unit 20 determines that the liquid level of the cleaning liquid in the tank 32 is lower than the predetermined height.

<About constant volume pump>
The constant displacement pump 80 will be described with reference to FIGS. 7 to 10, the arrow A2 indicates the upper side of the constant displacement pump 80, and the arrow B2 indicates the lower side of the constant displacement pump 80. 7 to 10, a pump first direction orthogonal to the pump vertical direction is indicated by arrows C2 and D2, and a pump second direction orthogonal to the pump vertical direction and the pump first direction is indicated by arrows E2 and F2. Is shown.

  As shown in FIG. 7, the constant displacement pump 80 is formed in a substantially cylindrical shape extending in the pump second direction as a whole. The constant displacement pump 80 includes a cylinder 82, and a piston 104 (see FIG. 8) and a moving mechanism 110 (see FIG. 8) provided in the cylinder 82. The constant displacement pump 80 includes a pump inlet 130 as an “inlet”, a pump outlet 132 as an “outlet”, a first check valve 134 (see FIG. 8), and a second check valve 142 (FIG. 8). See). Hereinafter, a specific description will be given.

(About cylinder)
As shown in FIGS. 8 and 9, the cylinder 82 is formed in a substantially cylindrical shape with the pump second direction as the axial direction. A portion on one axial side (arrow F2 side) of the cylinder 82 is a piston housing portion 84 as a “housing portion” for housing the piston 104, which will be described later. The portion (E2 side) is a solenoid housing portion 86 for housing a solenoid 114 described later. Further, inside the cylinder 82, a partition wall 88 (see FIG. 9) that partitions the inside of the piston housing portion 84 and the inside of the solenoid housing portion 86 is provided. Thus, the piston housing portion 84 is formed in a substantially bottomed cylindrical shape that is open to one axial side of the cylinder 82, and the partition wall 88 forms the bottom wall of the piston housing portion 84. Further, the solenoid housing portion 86 is set to have a larger diameter than the piston housing portion 84, and the lower portion of the solenoid housing portion 86 extends downward when viewed from the axial direction of the cylinder 82. It is formed in a substantially U-shape opened upward when viewed from the axial direction.

  As shown in FIG. 9, in the center of the partition wall 88, on the surface on the side of the solenoid housing 86, a seal housing 88 </ b> A having a concave shape and open to the other axial side of the cylinder 82 (direction of arrow E <b> 2). The seal accommodating portion 88 </ b> A is formed in a circular shape when viewed from the other axial side of the cylinder 82. A substantially annular seal member 90 is provided in the seal accommodating portion 88A. Further, a circular insertion hole 88B is formed through the bottom surface of the seal accommodating portion 88A at the center thereof. Then, an end of a plunger 114B of the solenoid 114 described later is inserted into the inside of the seal member 90 and the insertion hole 88B. Thereby, the space between the inside of the piston housing 84 and the inside of the solenoid housing 86 is sealed by the seal member 90. Further, as shown in FIG. 10, a plurality of (two in the present embodiment) protrusions 88 </ b> C are formed on the surface of the partition wall 88 on the piston housing portion 84 side. The projection 88C is formed in a substantially columnar shape having a relatively low height.

  As shown in FIGS. 8 and 9, a pair of upper and lower first fixing portions 84 </ b> A for fixing a first cap 100, which will be described later, are integrally formed on the outer peripheral portion of the opening end of the piston housing portion 84. ing. The first fixing portion 84A is formed in a substantially cylindrical shape extending in the axial direction of the piston accommodating portion 84, and is opened to one axial side of the cylinder 82 at the center of the first fixing portion 84A. A first fixing recess 84A1 is formed.

  A substantially cylindrical inflow cylindrical portion 84B is formed integrally with the side wall forming the outer peripheral portion of the piston housing portion 84 at the base end side (the partition wall 88 side) of the piston housing portion 84 and below the pump. The inflow cylinder portion 84B projects from the piston housing portion 84 to the lower side of the pump. As shown in FIG. 9, a spring housing portion 84C for housing an end portion of a valve urging spring 140 described later is formed on the side wall of the piston housing portion 84 inside the inflow cylinder portion 84B. The spring accommodating portion 84C is formed in a concave shape that is open to the lower side of the pump (that is, the inner side of the inflow cylindrical portion 84B). A substantially circular inflow hole 84D is vertically penetrated through the bottom surface of the spring housing portion 84C. Thus, the inside of the piston housing portion 84 and the inside of the inflow cylinder portion 84B are communicated by the inflow hole 84D. The opening of the inflow hole 84D on the inner side of the piston housing portion 84 is disposed adjacent to the partition wall 88.

  As shown in FIGS. 8 and 9, on the side wall of the piston accommodating portion 84, at the base end side (the partition wall 88 side) of the piston accommodating portion 84 and at a position above the pump, a substantially cylindrical outflow cylindrical portion 84E is formed. Are formed integrally, and the outflow tube portion 84E projects from the piston housing portion 84 toward the upper side of the pump. Further, as shown in FIG. 9, an outflow hole 84F communicating between the inside of the piston housing 84 and the inside of the outflow cylinder 84E is formed through the side wall of the piston housing 84 inside the outflow cylinder 84E. Have been. The outflow hole 84F is formed in a circular cross section, and is set so that the inner diameter of the outflow hole 84F becomes smaller toward the radially inner side of the piston housing portion 84. The opening of the outflow hole 84F on the inner side of the piston housing portion 84 is arranged adjacent to the partition wall 88.

  As shown in FIG. 8, a plurality of (four in the present embodiment) second fixing portions 86 </ b> A for fixing a second cap 102, which will be described later, are provided on the outer peripheral portion at the open end of the solenoid housing portion 86. It is formed integrally (only three second fixing portions 86A are shown in FIG. 8). The second fixing portion 86A is formed in a substantially cylindrical shape extending in the axial direction of the solenoid accommodating portion 86, and is opened to the other axial side of the cylinder 82 at the center of the second fixing portion 86A. A second fixing recess 86A1 is formed.

  As shown in FIG. 9, a seal groove 86 </ b> B is formed on the open end surface of the solenoid housing 86, and the seal groove 86 </ b> B is formed over the entire circumference of the open end of the solenoid housing 86 in the circumferential direction. ing. A seal member 92 is arranged inside the seal groove 86 </ b> B, and the seal member 92 is formed in a frame shape corresponding to the shape of the open end of the solenoid housing 86.

  As shown in FIG. 8, a pump mounting portion 82A is integrally formed on a side wall that constitutes the outer peripheral portion of the solenoid housing portion 86 at a portion on one side in the pump first direction. The pump mounting portion 82A is formed in a substantially C shape that is open to one side in the pump first direction when viewed from above. Further, on the side wall of the solenoid accommodating portion 86, an engagement projection 82B protruding outside the solenoid accommodating portion 86 is integrally formed at the position of the pump mounting portion 82A.

  The constant displacement pump 80 is mounted on the back door via the pump mounting plate 94 at the position of the pump mounting portion 82A. Specifically, the pump mounting plate 94 is formed in a substantially T-shaped plate shape with the pump first direction being the plate thickness direction, and the lower end of the pump mounting plate 94 is fitted into the inside of the pump mounting portion 82A. I have. A substantially rectangular engagement hole 94A is formed through the lower end of the pump mounting plate 94. When the pump mounting plate 94 is fitted into the pump mounting portion 82A, the engagement projection 82B of the constant displacement pump 80 is disposed in the engagement hole 94A, and the engagement hole 94A and the engagement projection 82B are moved in the vertical direction of the pump. Is engaged. Thus, upward movement of the pump mounting plate 94 is restricted.

  The opening of the piston housing portion 84 is closed by the first cap 100. The first cap 100 includes a substantially disk-shaped first cap body 100A in which the axial direction of the piston accommodating portion 84 is a plate thickness direction. A pair of flange portions 100B projecting upward and downward from the pump are formed integrally with the outer peripheral portion of the first cap body 100A, and a first fixing hole 100C is formed through the flange portion 100B. I have. The first fixing hole 100C is arranged coaxially with the first fixing concave portion 84A1 of the piston accommodating portion 84, and the screw S2 is inserted into the first fixing hole 100C and screwed into the first fixing concave portion 84A1. Thus, the first cap 100 is fixed to the piston housing portion 84 (cylinder 82). Thus, the opening of the piston housing portion 84 is closed by the first cap 100.

  As shown in FIG. 9, a substantially cylindrical rib 100 </ b> D is integrally formed on the outer peripheral portion of the first cap main body 100 </ b> A on a surface on the side of the piston housing portion 84. It is fitted inside the opening edge. On the outer peripheral surface of the rib 100D, a seal groove 100E extending along the circumferential direction of the rib 100D is formed, and the seal groove 100E extends over the entire circumference of the rib 100D. A substantially annular seal member 96 is provided in the seal groove 100E, and the space between the first cap 100 and the piston housing portion 84 is sealed by the seal member 96.

  As shown in FIG. 8, a communication portion 100 </ b> F that connects the inside and the outside of the piston housing portion 84 is formed on a surface of the first cap body 100 </ b> A on the side opposite to the piston housing portion 84, The portion 100F extends in the up-down direction. Further, a pump communication passage 100G is formed inside the communication portion 100F. The pump communication passage 100G extends upward from the lower end of the communication portion 100F to the pump and is bent toward the piston housing portion 84. Thus, the inside and the outside of the piston housing portion 84 are communicated by the pump communication passage 100G.

  On the other hand, the opening of the solenoid housing 86 is closed by the second cap 102. The second cap 102 includes a cylindrical second cap body 102A having a shallow bottom and open to the solenoid housing 86 side. The outer shape of the second cap body 102A is the open end of the solenoid housing 86. It has a shape corresponding to the part. As shown in FIG. 8, four flange portions 102B are formed integrally on the outer peripheral portion of the second cap body 102A so as to protrude to the outside of the second cap body 102A. Has a second fixing hole 102C formed therethrough (in FIG. 8, only three flange portions 102B and the second fixing hole 102C are shown). The second fixing hole 102C is arranged coaxially with the second fixing recess 86A1 of the solenoid housing 86, and the screw S3 is inserted into the second fixing hole 102C and screwed into the second fixing recess 86A1. As a result, the second cap 102 is fixed to the solenoid housing portion 86 (cylinder 82). Thus, the opening of the solenoid housing 86 is closed by the second cap 102, and the gap between the opening end of the solenoid housing 86 and the second cap 102 is sealed by the seal member 92.

  Further, a rib 102D is integrally formed on the outer peripheral portion of the second cap 102 on the surface on the side of the solenoid housing portion 86, and the rib 102D is formed over the entire circumference of the second cap 102 in the circumferential direction. I have. The rib 102D is fitted into the opening edge of the solenoid housing 86 (see FIG. 9).

  Further, a pair of arms 102E is integrally formed at the tip of the rib 102D, and the arm 102E protrudes from the rib 102D toward the solenoid housing 86. The arm portion 102E is formed in a curved plate shape that is curved in a substantially arc shape when viewed from the axial direction of the cylinder 82, and holds a solenoid main body 114A described later from the outside and is housed in a solenoid housing portion 86. I have. Further, a slit 102F is formed at the tip of the arm portion 102E, and the slit 102F extends along the circumferential direction of the second cap 102.

(About piston)
As shown in FIGS. 8 and 9, the piston 104 is formed in a substantially bottomed cylindrical shape that is open to one axial side of the cylinder 82 (in other words, the opening side of the piston housing portion 84). The outer diameter of the piston 104 is set slightly smaller than the inner diameter of the piston accommodating portion 84, and the piston 104 is disposed coaxially with the piston accommodating portion 84 of the cylinder 82, and is located inside the piston accommodating portion 84. Is housed. Accordingly, the piston 104 is configured to be able to reciprocate in the piston housing portion 84 in the axial direction of the cylinder 82 (piston 104). In the following description, the movement of the piston 104 in one axial direction (the direction of the arrow F2 in FIGS. 8 and 9) is defined as the forward movement, and the other axial direction of the piston 104 (the arrow E2 in FIGS. 8 and 9). The movement in the direction (direction side) is a return movement.

  Further, the bottom wall portion 104A of the piston 104 corresponds to the “tip portion of the piston” of the present invention, and the bottom wall portion 104A and the partition wall 88 face each other in the axial direction (moving direction) of the piston 104. Have been. A region (space) between the bottom wall portion 104A of the piston 104 and the partition wall 88 in the piston housing portion 84 is a pump chamber 106. Further, when the constant displacement pump 80 is not operating, the bottom wall portion 104A of the piston 104 is in contact with the projection 88C of the partition wall 88 described above. In the following description, the position of the piston 104 is set as the initial position. At the initial position, a small gap is formed between the bottom wall 104A of the piston 104 and the partition wall 88. .

  Further, in a state where the piston 104 is located at the initial position, the open end of the piston 104 is arranged to face the tip of the rib 100D of the first cap 100 in the axial direction of the piston 104, and is located at the tip of the rib 100D. On the other hand, it is separated to the other axial side of the piston 104. Thus, the stroke St (see FIG. 9) when the piston 104 reciprocates between the open end of the piston 104 and the tip of the rib 100 </ b> D, and the open end of the piston 104 is The position at which the rib 100D is in contact with the tip is the stroke end of the piston 104.

  Further, a piston seal groove 104B is formed in the outer peripheral portion of the piston 104 at a position on one side in the axial direction. The piston seal groove 104 </ b> B extends along the circumferential direction of the piston 104 and is formed over the entire circumference of the piston 104. A substantially annular seal member 98 (see FIG. 9) is provided inside the piston seal groove 104B, and the seal member 98 seals between the piston 104 and the piston housing portion 84. Thereby, the inside of the pump chamber 106 is kept airtight. The space inside the piston 104 and the outside of the piston housing portion 84 are communicated with each other by the pump communication passage 100G of the first cap 100 described above. Thereby, the pressure of the air inside the piston 104 is prevented from increasing during the reciprocating movement of the piston 104.

  Further, inside the piston 104, a piston urging spring 112 constituting a moving mechanism 110 described later is provided. The piston urging spring 112 is configured as a compression coil spring, and is arranged coaxially with the piston 104. Then, in a state where the piston urging spring 112 is compressed and deformed, one end of the piston urging spring 112 abuts on the first cap 100 on the radially inner side of the rib 100D, and the other end of the piston urging spring 112 Is in contact with the bottom wall 104A of the piston 104. Accordingly, when the constant displacement pump 80 is not operated, the piston 104 is biased toward the backward movement side and is arranged at the initial position.

(About moving mechanism)
As shown in FIGS. 8 and 9, the moving mechanism 110 includes the above-described piston urging spring 112 and a solenoid 114 (in a broad sense, an element grasped as a “driving member”). Have been.

  The solenoid 114 is housed in the solenoid housing 86 of the cylinder 82 described above. The solenoid 114 is configured as, for example, a DC solenoid, and includes a substantially cylindrical solenoid main body 114A, a plunger 114B forming an axial center portion of the solenoid 114, a pressing spring 120 for biasing the plunger 114B, It is comprised including.

  An outer shell of the solenoid main body 114A is constituted by a substantially bottomed cylindrical frame, and a fixed iron core (not shown) and a wound coil are arranged inside the frame. Then, a lead wire 116 connected to a terminal of the coil extends to the outside of the cylinder 82 via a bush 118 attached to a lower end portion of the solenoid housing 86 and is connected to the control unit 20. Thus, the solenoid 114 operates under the control of the control unit 20.

  A substantially circular plate 114C is fixed to one axial side of the solenoid body 114A. At the center of the plate 114C, there is formed a plate recess 114C1 that is open to one side in the axial direction of the solenoid main body 114A. The plate recess 114C1 is integrally formed with a cylindrical support portion 114C2. When the solenoid 114 is housed in the solenoid housing 86, the tip of the support 114C2 is disposed in the seal housing 88A and presses the seal member 90. In this state, the solenoid body 114A is held from the radial outside by the pair of arms 102E of the second cap 102, and the plate 114C is pressed toward the partition wall 88 by the tip of the arm 102E.

  The plunger 114B is arranged at the axis of the solenoid main body 114A, and is arranged coaxially with the piston 104. One end of the plunger 114B in the axial direction is inserted into the support portion 114C2 of the plate 114C, the seal member 90, and the insertion hole 88B of the partition wall 88, and one end of the plunger 114B in the axial direction is a bottom wall of the piston 104. It is in contact with the portion 104A. A stopper 114B1 is provided at the other end of the plunger 114B in the axial direction, and the stopper 114B1 is arranged on the other axial side with respect to the solenoid body 114A. When the solenoid 114 is actuated (turned on), the plunger 114 </ b> B moves to one side in the axial direction against the urging force of the piston urging spring 112, and presses the piston 104.

  The pressing spring 120 is provided between the stopper 114B1 of the plunger 114B and the second cap 102. The pressing spring 120 is configured as a compression coil spring. One end of the pressing spring 120 is in contact with the stopper 114B1, and the other end of the pressing spring 120 is in contact with the second cap 102. Thus, when the constant displacement pump 80 is not operated, one end of the plunger 114B and the bottom wall portion 104A of the piston 104 are in contact with each other.

(About pump inlet)
The pump inlet 130 is formed in a substantially cylindrical shape whose axial direction is the pump vertical direction, and the inside of the pump inlet 130 is an inflow passage 130A. The upper end (base end) of the pump inlet 130 is integrally formed with an inlet mounting portion 130B having an enlarged diameter, and the inlet mounting portion 130B is formed inside the opening end of the inflow cylindrical portion 84B of the cylinder 82. It is inserted in. Thereby, the inside of the inflow cylinder portion 84B and the outside of the pump inlet 130 are communicated by the inflow passage 130A. The other end of the second hose H2 described above is connected to the pump inlet 130. Thus, when the constant volume pump 80 is operated, the cleaning liquid in a state where the gas is separated by the gas-liquid separation device 30 is sucked into the pump chamber 106 via the pump inlet 130.

(About pump outlet)
The pump outlet 132 is formed in a substantially cylindrical shape whose axial direction is the pump vertical direction, and the inside of the pump outlet 132 is an outflow passage 132A. At the lower end (base end) of the pump outlet 132, an outlet mounting portion 132B having an enlarged diameter is integrally formed, and the outlet mounting portion 132B is formed inside the opening end of the outflow tube portion 84E of the cylinder 82. It is inserted in. Thus, the inside of the outflow tube portion 84E and the outside of the pump outlet 132 are communicated by the outflow passage 132A. The pump outlet 132 is connected to one end of the third hose H3 described above. Thus, when the constant volume pump 80 is operated, the cleaning liquid discharged from the pump chamber 106 is supplied to the optical sensor cleaning nozzle 150 described later. At the lower end of the pump outlet 132, a spring accommodating portion 132C (see FIG. 9) for accommodating an end of a valve urging spring 148 described later is formed. It is formed in a concave shape open to the side.

(About the first check valve)
The first check valve 134 is provided in the inflow cylinder portion 84B (that is, between the pump inlet 130 and the inflow hole 84D of the piston housing portion 84). Further, the first check valve 134 is configured to include a valve body 136 and a seal portion 138. The valve body 136 is formed in a substantially columnar shape with the vertical direction as the axial direction. On the upper surface of the valve body 136, an annular groove 136A opened upward is formed. The seal portion 138 is formed in a substantially bottomed cylindrical shape opened upward, and the lower end portion of the valve body 136 is inserted into the seal portion 138 so that the seal portion 138 is mounted on the valve body 136. . Thereby, the first check valve 134 is formed in a substantially columnar shape with the vertical direction as the axial direction as a whole. Further, a part of the outer peripheral portion of the first check valve 134 is cut away, and the outer shape of the first check valve 134 is formed in a substantially D-shape when viewed from the axial direction. As a result, a gap is formed between the notched portion of the first check valve 134 and the inner peripheral surface of the inflow cylinder 84B.

  Further, a valve urging spring 140 for urging the first check valve 134 is provided in the inflow cylinder portion 84B, and the valve urging spring 140 is a compression coil spring whose axial direction is the vertical direction. It is configured. One end (lower end) of the valve urging spring 140 is inserted into the groove 136A of the valve body 136 in a state where the valve urging spring 140 is compressed and deformed. The end (upper end) is housed in a spring housing 84C of the cylinder 82 (see FIG. 9). As a result, the first check valve 134 is urged toward the pump inlet 130 by the valve urging spring 140, and when the constant displacement pump 80 is not in operation, the pump portion is turned by the seal portion 138 of the first check valve 134. Inlet 130A of inlet 130 is closed.

(About the second check valve)
The second check valve 142 is provided inside the outflow tube portion 84E (that is, between the pump outlet 132 and the outflow hole 84F of the piston housing portion 84). The second check valve 142 has the same configuration as the first check valve 134. That is, the second check valve 142 is configured to include the valve main body 144 and the seal portion 146. The valve body 144 is formed in a substantially columnar shape with the vertical direction as the axial direction. On the upper surface of the valve body 144, an annular groove 144A opened upward is formed. On the other hand, the seal portion 146 is formed in a substantially bottomed cylindrical shape opened upward, and the lower end portion of the valve body 144 is inserted into the seal portion 138 so that the seal portion 146 is mounted on the valve body 144. ing. Thereby, the second check valve 142 is formed in a substantially columnar shape with the vertical direction as the axial direction as a whole. Further, a part of the outer peripheral portion of the second check valve 142 is cut out, and the outer shape of the second check valve 142 is formed in a substantially D-shape when viewed from the axial direction. As a result, a gap is formed between the notched portion of the second check valve 142 and the inner peripheral surface of the outflow tube portion 84E.

  Further, a valve urging spring 148 for urging the second check valve 142 is provided in the inflow cylindrical portion 84B, and the valve urging spring 148 is a compression coil spring whose axial direction is the vertical direction. It is configured. One end (lower end) of the valve urging spring 148 is inserted into the groove 136A of the valve main body 136 in a state where the valve urging spring 148 is compressed and deformed. The end (upper end) is housed in the spring housing 132C of the pump outlet 132. As a result, the first check valve 134 is urged toward the piston accommodating portion 84 by the valve urging spring 148, and when the constant displacement pump 80 is not operated, the piston is actuated by the seal portion 146 of the second check valve 142. Outflow hole 84F of accommodation part 84 is closed.

<About the optical sensor cleaning nozzle>
Next, the optical sensor cleaning nozzle 150 will be described with reference to FIG. As shown in this figure, the optical sensor cleaning nozzle 150 is formed in a substantially columnar shape as a whole. In FIG. 11, the tip side (one side in the axial direction) of the optical sensor cleaning nozzle 150 is indicated by an arrow B3, and the base end side (the other side in the axial direction) of the optical sensor cleaning nozzle 150 is indicated by an arrow A3.

  The optical sensor cleaning nozzle 150 includes a cylinder housing 152 that configures a distal portion of the optical sensor cleaning nozzle 150, and a proximal housing 160 that configures a proximal portion of the optical sensor cleaning nozzle 150. Have been. The optical sensor cleaning nozzle 150 has a piston unit 170 disposed inside the optical sensor cleaning nozzle 150. Hereinafter, each configuration will be described.

(About cylinder housing)
The cylinder housing 152 is formed in a substantially cylindrical shape extending in the axial direction of the optical sensor cleaning nozzle 150. A substantially cylindrical spring holder 154 for holding a return spring 178 to be described later is mounted on a distal end portion of the cylinder housing 152.

(About the proximal housing)
The proximal housing 160 includes an inlet member 162, a cap member 164, a check valve 166 for cleaning liquid, and a check valve 168 for air. The inlet member 162 has a substantially cylindrical inlet main body 162A. The outer diameter of the proximal end portion of the inlet main body 162A is set substantially equal to the outer diameter of the cylinder housing 152, and the distal end portion of the inlet main body 162A is located on the proximal end side of the inlet main body 162A. It is formed to have a larger diameter than the portion. Then, the base end of the cylinder housing 152 is fitted from the distal end side of the inlet main body 162A, and the inlet member 162 and the cylinder housing 152 are integrated.

  The distal end portion of the inlet member 162 is constituted by a cylindrical inlet portion 162B. The inlet portion 162B is disposed inside the inlet main body portion 162A (cylinder housing 152) and is connected to the cylinder housing 152. They are arranged coaxially. The base end of the inlet 162B is connected to an axially intermediate portion of the inlet main body 162A by a substantially cylindrical connecting portion 162C. Further, the inner peripheral surface of the connecting portion 162C is formed in a substantially conical shape so as to become wider toward the base end side of the inlet member 162. Thereby, the internal space of the inlet member 162 is narrowed by the connecting portion 162C, and the inner diameter of the inlet portion 162B is set smaller than the inner diameter of the inlet member 162 on the base end side.

  The cap member 164 has a substantially bottomed cylindrical cap body 164A that is open to the distal end side of the optical sensor cleaning nozzle 150, and the base end of the inlet member 162 is fitted inside the cap body 164A. I have. The cap member 164 has a pair of substantially cylindrical inlets. The inlet extends from the top wall of the cap body 164A to the tip side of the optical sensor cleaning nozzle 150. One of the pair of inlets is a cleaning liquid inlet 164B, and a communication path 164B1 that connects the outside of the cleaning liquid inlet 164B and the inside of the inlet member 162 is formed inside the cleaning liquid inlet 164B. I have. Specifically, the communication path 164B1 extends substantially linearly from the tip of the cleaning liquid inlet 164B toward the inlet member 162, and is obliquely bent at the top wall of the cap body 164A. The other end of the third hose H3 is connected to the cleaning liquid inlet 164B. Accordingly, the cleaning liquid discharged from the constant volume pump 80 is pressure-fed to the inside of the inlet member 162 via the cleaning liquid inlet 164B.

  The other of the pair of inlets described above is an air inlet 164C. Inside the air inlet 164C, there is formed a communication passage 164C1 for communicating the outside of the air inlet 164C with the inside of the inlet member 162. Specifically, the communication passage 164C1 extends substantially linearly from the tip of the air inlet 164C to the inlet member 162 side. One end of a fourth hose H4 is connected to the air inlet 164C, and the other end of the fourth hose H4 is connected to the air pump 18. Thus, high-pressure air from the air pump 18 is supplied to the inside of the inlet member 162 via the air inlet 164C.

  The cleaning liquid check valve 166 is arranged in the base end of the inlet member 162 so that the inside of the cleaning liquid inlet 164 </ b> B communicates with the inside of the inlet member 162. Further, the air check valve 168 is disposed in the base end of the inlet member 162 so that the inside of the air inlet 164 </ b> C communicates with the inside of the inlet member 162. The check valve 166 for the cleaning liquid and the check valve 168 for the air are formed in a cylindrical shape whose axial direction is the vertical direction, and are configured as duckbill check valves whose lower ends are narrowed.

(About piston unit)
The piston unit 170 includes a piston nozzle member 172, a piston outer member 174, and a lip packing 176. The piston nozzle member 172 is formed in a substantially cylindrical shape, and is arranged inside the cylinder housing 152. The inner diameter of the base end portion of the piston nozzle member 172 is set to be larger than the outer diameter of the inlet portion 162B, and the inlet portion 162B is loosely fitted inside the piston nozzle member 172. Thus, the piston nozzle member 172 is configured to be movable in the axial direction of the optical sensor cleaning nozzle 150.

  In addition, a nozzle portion 172A is formed at the tip of the piston nozzle member 172, and an injection port 172B that is opened radially outward of the piston nozzle member 172 is formed in the nozzle portion 172A. Further, a common introduction chamber 172C is formed inside the piston nozzle member 172 on the upstream side of the injection port 172B, and the common introduction chamber 172C is supplied with air supplied from the air pump 18 and supplied from the constant volume pump 80. It is a shared introduction chamber into which the cleaning liquid is introduced.

  The piston outer member 174 is formed in a substantially cylindrical shape. Then, the base end side portion of the piston nozzle member 172 is fitted into the piston outer member 174, and the piston nozzle member 172 and the piston outer member 174 are integrated. In addition, a substantially annular flange 174A extending outward in the radial direction is integrally formed at the base end of the piston outer member 174. The outer diameter of the flange 174A is smaller than the inner diameter of the cylinder housing 152. Is set slightly smaller. Further, a substantially cylindrical packing mounting portion 174B protruding toward the base end side of the optical sensor cleaning nozzle 150 is integrally formed with the flange portion 174A. A retaining groove 174C that is opened radially outward of the packing mounting portion 174B is formed on an outer peripheral portion of the packing mounting portion 174B. Is formed.

  The lip packing 176 is formed in a substantially cylindrical shape extending in the axial direction of the optical sensor cleaning nozzle 150, and is mounted on the packing mounting section 174B radially outside the packing mounting section 174B. An annular retaining rib 176A protruding radially inward is integrally formed at the tip of the lip packing 176, and the retaining rib 176A is disposed in the retaining groove 174C. Thereby, the relative movement of the piston outer member 174 of the lip packing 176 in the axial direction of the optical sensor cleaning nozzle 150 is restricted. The outer peripheral portion of the lip packing 176 is slidably in contact with the inner periphery of the cylinder housing 152.

  Further, a return spring 178 for urging the piston unit 170 is provided inside the cylinder housing 152, and the return spring 178 is configured as a compression coil spring. Then, in a state where the return spring 178 is compressed and deformed, one end of the return spring 178 is in contact with the spring holder 154, and the other end of the return spring 178 is in contact with the flange 174A of the piston outer member 174. I have. As a result, the piston unit 170 is urged toward the base end side of the optical sensor cleaning nozzle 150, and the piston outer member 174 is in contact with the connecting portion 162C of the inlet member 162 (the piston unit 170 shown in FIG. 11). (Hereinafter, this position is referred to as a non-cleaning position).

  When the constant volume pump 80 operates, the cleaning liquid is stored in the common introduction chamber 172C. When the air pump 18 operates, high-pressure air is supplied to the common introduction chamber 172C. Thereby, the optical sensor cleaning nozzle 150 operates. Specifically, the piston unit 170 extends from the non-cleaning position to the tip side of the optical sensor cleaning nozzle 150 by the supply pressure of the air when the air is supplied to the shared introduction chamber 172C. The cleaning liquid is sprayed toward the lens when approaching the lens.

  Next, the operation and effect of the present embodiment will be described.

  In the on-vehicle optical sensor cleaning device 10 configured as described above, the washer tank 12 (washer pump 14) and the gas-liquid separator 30 are connected by the first hose H1, and the gas-liquid separator 30 and the constant volume pump are connected. 80 are connected by a second hose H2. As a result, when the washer pump 14 is operated by the control unit 20, the cleaning liquid pumped by the washer pump 14 flows into the gas-liquid separator 30 via the first hose H1, and is also discharged from the gas-liquid separator 30. The gas flows into the pump inlet 130 (in the inflow passage 130A) of the constant displacement pump 80 via the second hose H2.

  Further, the control unit 20 determines whether or not the liquid level of the cleaning liquid in the tank 32 is at a predetermined height based on a detection signal from the liquid level sensor 70 of the gas-liquid separation device 30. Then, when the liquid level of the cleaning liquid in the tank 32 is lower than the predetermined height, the control unit 20 operates the washer pump 14 so that the liquid level of the cleaning liquid becomes the predetermined height. Specifically, the cleaning liquid pumped by the washer pump 14 flows into the gas-liquid separator 30 via the first hose H1, and when the liquid level of the cleaning liquid in the tank 32 reaches a predetermined height, the liquid level increases. The electrodes 74A and 74B of the sensor 70 are energized by the cleaning liquid. Thus, the control unit 20 determines that the level of the cleaning liquid in the tank 32 has reached the predetermined height, and stops the operation of the washer pump 14. As a result, the interior of the tank 32 is filled with the cleaning liquid at a predetermined height.

  Further, when air (gas) in the atmosphere passes through the first hose H1 and is mixed into the cleaning liquid in the first hose H1, the cleaning liquid having bubbles flows into the tank 32 of the gas-liquid separator 30. However, in the tank 32, the cleaning liquid and the air are separated. Specifically, the separated cleaning liquid is filled in the lower part of the tank 32, and the separated air is discharged from the upper part of the tank 32 to the outside of the tank 32 via the gas discharge outlet 64. Thus, the cleaning liquid from which the air has been separated is supplied from the gas-liquid separator 30 to the constant volume pump 80.

  Then, when cleaning the on-vehicle camera 16, by turning on the cleaning switch of the vehicle, the constant displacement pump 80 operates and the air pump 18 operates. As a result, the optical sensor cleaning nozzle 150 is operated, and the cleaning liquid is ejected from the optical sensor cleaning nozzle 150 toward the vehicle-mounted camera 16. Hereinafter, the operation of the constant volume pump 80 and the operation of the optical sensor cleaning nozzle 150 will be described separately.

(Operation of constant displacement pump)
When the constant displacement pump 80 is not operated, the piston 104 is located at an initial position where the piston 104 is in contact with the projection 88C of the piston housing portion 84. The first check valve 134 is urged downward by the valve urging spring 140 to close the inflow passage 130A of the pump inlet 130. Further, the second check valve 142 is biased downward by the valve biasing spring 148 to close the outflow hole 84F of the piston housing portion 84.

  When the washing switch of the vehicle is turned on, the solenoid 114 of the constant displacement pump 80 operates under the control of the control unit 20. Specifically, when the solenoid 114 is turned on, the plunger 114B moves to one axial side of the cylinder 82 against the urging force of the piston urging spring 112. For this reason, the piston 104 is pushed to one side in the axial direction of the cylinder 82 by the plunger 114B and moves to the forward movement side, and is arranged at the stroke end position. At this time, the pressure in the pump chamber 106 becomes negative, and the first check valve 134 moves upward of the pump against the urging force of the valve urging spring 140. As a result, the inflow path 130A of the pump inlet 130 is opened, and the cleaning liquid in the inflow path 130A is sucked into the pump chamber 106, and the pump chamber 106 is filled with the cleaning liquid. At this time, the closed state of the piston housing portion 84 to the outflow hole 84F by the second check valve 142 is maintained.

  On the other hand, when the piston 104 reaches the stroke end position and the solenoid 114 is turned off, the plunger 114B is moved to the reversing side by the urging force of the piston urging spring 112 and is located at the initial position. . At this time, the cleaning liquid in the pump chamber 106 is compressed, and the pressure of the cleaning liquid causes the second check valve 142 to move upward of the pump against the urging force of the valve urging spring 148. Therefore, the outflow hole 84F of the piston housing portion 84 is opened, and the cleaning liquid in the pump chamber 106 is discharged at a high pressure from the outflow passage 132A of the pump outlet 132. Thus, a constant volume of the cleaning liquid is pumped from the constant volume pump 80 to the cleaning liquid inlet 164B of the optical sensor cleaning nozzle 150 via the third hose H3. At this time, the pressure of the cleaning liquid acts on the first check valve 134, but the first check valve 134 closes the inflow passage 130 </ b> A of the pump inlet 130. Backflow from 130 to the second hose H2 side is suppressed. By repeating the reciprocating movement of the piston 104 a plurality of times, a constant volume of the cleaning liquid is supplied from the constant volume pump 80 to the optical sensor cleaning nozzle 150.

(Operation of the optical sensor cleaning nozzle 150)
When the cleaning liquid is pumped into the cleaning liquid inlet 164B of the optical sensor cleaning nozzle 150 by operating the constant volume pump 80, the cleaning liquid is supplied to the inside of the inlet member 162 via the cleaning liquid check valve 166. Further, the cleaning liquid supplied to the inside of the inlet member 162 is stored in the shared introduction chamber 172C so as to close the injection port 172B of the piston nozzle member 172.

  On the other hand, the control unit 20 operates the air pump 18 after the operation of the constant displacement pump 80. Thus, high-pressure air is sent from the air pump 18 to the air inlet 164C of the optical sensor cleaning nozzle 150 via the fourth hose H4. The air fed to the air inlet 164 </ b> C is supplied to the inside of the inlet member 162 via the check valve for air 168, and is also supplied to the inside of the piston nozzle member 172. As a result, the cleaning liquid and air stored in the shared introduction chamber 172C are mixed, and the cleaning liquid and air are injected from the injection port 172B as a gas-liquid mixed fluid.

  Also, at this time, the piston unit 170 extends from the non-cleaning position to the tip side of the optical sensor cleaning nozzle 150 due to the air supply pressure when air is supplied to the shared introduction chamber 172C, and is transmitted to the lens of the vehicle-mounted camera 16. When approaching, the cleaning liquid is sprayed toward the lens. Thereby, the lens of the in-vehicle camera 16 is cleaned.

  Here, in the in-vehicle optical sensor cleaning device 10, as described above, the constant displacement pump 80 is provided between the washer pump 14 and the injection port 172B of the optical sensor cleaning nozzle 150. Is activated, a constant volume of the cleaning liquid is supplied to the injection port 172B of the optical sensor cleaning nozzle 150. Therefore, even if the operating voltage of the washer pump 14 fluctuates or the temperature, concentration, and viscosity of the cleaning liquid fluctuate due to fluctuations in the use environment temperature, the constant volume pump 80 applies a constant volume of the cleaning liquid to the optical sensor cleaning nozzle. It can be supplied to 150 injection ports 172B. Thus, it is possible to suppress the consumption of the cleaning liquid in the washer tank 12 from increasing.

  Further, in the on-vehicle optical sensor cleaning device 10, the constant volume pump 80 is disposed at a position closer to the optical sensor cleaning nozzle 150 than the washer pump 14, and the length of the third hose H3 is equal to the length of the first hose H1 and the second hose H2. It is set to be significantly shorter than the total length of the hose H2. For this reason, it is possible to suppress a variation in the amount of the cleaning liquid supplied to the optical sensor cleaning nozzle 150 due to air entering the cleaning liquid. That is, with the connection of the optical sensor cleaning nozzle 150, the constant volume pump 80, and the washer pump 14, there is a possibility that air that has passed through the hoses enters the cleaning liquid in the first hose H1, the second hose H2, and the third hose H3. There is. By arranging the constant volume pump 80 closer to the optical sensor cleaning nozzle 150 than the washer pump 14, the length of the third hose H3 connecting the constant volume pump 80 and the optical sensor cleaning nozzle 150 can be reduced. The length can be shorter than the total length of the first hose H1 and the second hose H2 connecting the constant displacement pump 80 and the washer pump 14. Therefore, intrusion of air into the cleaning liquid between the constant volume pump 80 and the optical sensor cleaning nozzle 150 can be suppressed. Therefore, it is possible to suppress a variation in the amount of the cleaning liquid supplied to the optical sensor cleaning nozzle 150 due to air entering the cleaning liquid. As a result, the constant volume pump 80 can satisfactorily supply a constant volume of the cleaning liquid to the injection port 172B of the optical sensor cleaning nozzle 150.

  Further, a gas-liquid separator 30 is provided between the washer pump 14 and the optical sensor cleaning nozzle 150, and a constant volume pump 80 is provided between the gas-liquid separator 30 and the optical sensor cleaning nozzle 150. Have been. Therefore, after the cleaning liquid and the gas contained in the cleaning liquid are separated by the gas-liquid separator 30 on the upstream side of the constant volume pump 80, the cleaning liquid can be supplied to the constant volume pump 80. Thus, the variation in the amount of the cleaning liquid supplied to the constant displacement pump 80 can be suppressed, and the variation in the amount of the cleaning liquid supplied to the optical sensor cleaning nozzle 150 can be suppressed.

  In the constant displacement pump 80, the cleaning liquid in the pump chamber 106 is pumped toward the optical sensor cleaning nozzle 150 by reciprocating movement of the piston 104 in the axial direction. Thus, the cleaning liquid discharged from the pump chamber 106 can be set at a high pressure, and the cleaning liquid can be supplied to the optical sensor cleaning nozzle 150 side.

  Further, the constant displacement pump 80 has a first check valve 134. When the piston 104 moves forward, the first check valve 134 opens the inflow passage 130A of the pump inlet 130 to allow the flow of the cleaning liquid from the pump inlet 130 to the pump chamber 106. Therefore, when the piston 104 moves forward, the first check valve 134 allows the cleaning liquid to flow into the pump chamber 106 satisfactorily. On the other hand, when the piston 104 moves backward, the first check valve 134 closes the inflow path 130A of the pump inlet 130 to suppress the flow of the cleaning liquid from the pump chamber 106 to the washer pump 14 side. Therefore, it is possible to prevent the cleaning liquid in the pump chamber 106 from flowing backward to the washer pump 14 when the piston 104 moves backward.

  Further, the constant displacement pump 80 has a second check valve 142. Then, when the piston 104 moves forward, the second check valve 142 closes the outflow hole 84F of the piston housing portion 84. Therefore, when the piston 104 moves forward, the second check valve 142 can prevent air from entering the pump chamber 106 through the outflow hole 84F. Further, when the piston 104 moves backward, the second check valve 142 opens the outflow hole 84F of the piston housing portion 84 to allow the flow of the cleaning liquid from the pump chamber 106 to the optical sensor cleaning nozzle 150 side. Therefore, when the piston 104 moves backward, the cleaning liquid in the pump chamber 106 can be satisfactorily discharged to the optical sensor cleaning nozzle 150 side.

  In the constant displacement pump 80, the bottom wall portion 104A of the piston 104 is in contact with the partition wall 88 of the cylinder 82 when the moving mechanism 110 (solenoid 114) is not operated. For this reason, the capacity of the pump chamber 106 when the moving mechanism 110 is not operated can be set small. That is, when the moving mechanism 110 is not operated, the residual amount of the cleaning liquid in the pump chamber 106 can be reduced. Accordingly, it is possible to prevent the cleaning liquid from leaking from the injection port 172B of the optical sensor cleaning nozzle 150. In other words, if the amount of the cleaning liquid remaining in the pump chamber 106 is large in the inoperative state of the moving mechanism 110, for example, when the constant volume pump 80 is exposed to a high temperature, the cleaning liquid thermally expands, The cleaning liquid in the chamber 106 may leak to the optical sensor cleaning nozzle 150. In this case, the cleaning liquid may leak out from the injection port 172B of the optical sensor cleaning nozzle 150. On the other hand, in the in-vehicle optical sensor cleaning device 10 having the above configuration, as described above, the residual amount of the cleaning liquid in the pump chamber 106 can be reduced when the moving mechanism 110 is not operating. Therefore, for example, even if the constant volume pump 80 is exposed to a high temperature, the cleaning liquid in the pump chamber 106 can be prevented from leaking to the optical sensor cleaning nozzle 150, and the cleaning liquid can be prevented from being injected into the injection port 172B of the optical sensor cleaning nozzle 150. Can be suppressed from leaking out.

  In the constant displacement pump 80, a protrusion 88C is formed on the surface of the partition wall 88 on the piston housing portion 84 side. Therefore, the piston 104 can be satisfactorily reciprocated when the moving mechanism 110 operates. That is, if the projection 88C is omitted from the partition wall 88, the bottom wall portion 104A of the piston 104 abuts against the partition wall 88. For this reason, there is a possibility that the bottom wall portion 104A of the piston 104 adheres to the partition wall 88 due to the cleaning liquid remaining in the pump chamber 106, and the piston 104 cannot be moved reciprocally well. On the other hand, in the present embodiment, a projection 88C is formed on the surface of the partition wall 88 on the piston housing portion 84 side. Therefore, the contact area between the bottom wall portion 104A of the piston 104 and the partition wall 88 can be reduced. This can prevent the bottom wall portion 104A of the piston 104 from sticking to the partition wall 88. Therefore, the piston 104 can be satisfactorily reciprocated when the moving mechanism 110 operates.

(Modification of constant displacement pump)
Next, a constant displacement pump 200 according to a modified example will be described with reference to FIGS. The present modified example has the same configuration as the constant displacement pump 80 of the present embodiment, except for the following points. In FIGS. 12 and 13, members and portions that are configured similarly to the constant displacement pump 80 of the present embodiment are denoted by the same reference numerals. In the constant displacement pump 200 of FIG. 12, the first cap 100, the second cap 102, and the moving mechanism 110 are not shown.

  In the constant displacement pump 200 of the modified example, the inflow cylinder portion 84B of the cylinder 82 (piston accommodating portion 84) is formed to have a larger diameter than in the present embodiment. Further, in the piston housing portion 84, the inflow hole 84D of the present embodiment is omitted, and the inside of the inflow tube portion 84B and the inside of the piston housing portion 84 communicate with each other (see FIG. 13). Further, as shown in FIG. 13, in the inflow cylinder portion 84B, the inner diameter on the distal end side is set to be larger than the inner diameter on the proximal end side. That is, a step surface 84G is formed on the inner peripheral surface of the inflow tube portion 84B at an axially intermediate portion of the inflow tube portion 84B, and the step surface 84G extends along a direction orthogonal to the pump vertical direction. Are located.

  The outflow cylinder portion 84E of the cylinder 82 (piston accommodating portion 84) is also formed to have a larger diameter than in the present embodiment. In the piston housing portion 84, the outflow hole 84F of the present embodiment is omitted, and the inside of the outflow tube portion 84E and the inside of the piston housing portion 84 are communicated. In the outflow tube portion 84E, the inner diameter on the distal end side is set to be larger than the inner diameter on the proximal end side. That is, a step surface 84H is formed on the inner peripheral surface of the outflow tube portion 84E at an axially intermediate portion of the outflow tube portion 84E, and the step surface 84H extends along a direction orthogonal to the pump vertical direction. Are located.

  An inflow-side cap 202 is provided in the inflow cylinder 84B. This inflow side cap 202 is formed in a substantially bottomed cylindrical shape opened to the lower side of the pump. Then, the inflow side cap 202 is fitted into the inflow cylinder portion 84B, and the top surface of the inflow side cap 202 is in contact with the step surface 84G (see FIG. 13). Thereby, in this modification, the pump chamber 106 is expanded to the inflow-side cap 202 in the inflow cylinder 84B.

  As shown in FIG. 12, a circular insertion hole 202A is formed through the center of the top wall of the inflow-side cap 202. A plurality (three in this embodiment) of inflow holes 202B are formed through the top wall of the inflow-side cap 202 outside the insertion hole 202A in the radial direction. The inflow holes 202B are arranged at equal intervals (every 120 °) in the circumferential direction of the inflow side cap 202.

  Further, as shown in FIG. 13, an outflow side cap 204 is provided in the outflow tube portion 84E. The outflow side cap 204 is configured symmetrically with the inflow side cap 202 in the vertical direction of the pump. That is, the outflow side cap 204 is formed in a substantially bottomed cylindrical shape opened to the upper side of the pump. Then, the outflow side cap 204 is fitted into the outflow cylinder portion 84E, and the bottom surface of the outflow side cap 204 is in contact with the step surface 84H. Thereby, in this modification, the pump chamber 106 is expanded to the outflow side cap 204 in the outflow cylinder portion 84E.

  As shown in FIG. 12, a circular insertion hole 204 </ b> A is formed through the center of the bottom wall of the outflow side cap 204. In the bottom wall of the outflow side cap 204, a plurality of (three in this embodiment) outflow holes 204B are formed to penetrate radially outside the insertion holes 204A. The outflow holes 204B are arranged at equal intervals (every 120 °) in the circumferential direction of the outflow side cap 204.

  As shown in FIGS. 12 and 13, in the present modification, the first check valve 206 and the second check valve 208 are configured as so-called umbrella valves. Since the first check valve 206 and the second check valve 208 have the same configuration, in the following description, the configuration of the first check valve 206 will be described, and the configuration of the second check valve 208 will be described. Description is omitted. In addition, each configuration of the second check valve 208 is the same as that of the first check valve 206 except that the reference numeral of each configuration is replaced with 208.

  The first check valve 206 is made of an elastic material such as rubber or elastomer. The first check valve 206 is configured to include a substantially disk-shaped valve body 206A and a shaft portion 206B protruding downward from the center of the valve body 206A. A bulging portion 206C slightly bulging radially outward is formed at an axially intermediate portion of the shaft portion 206B. Further, a tapered portion 206D is formed on the outer peripheral portion of the upper surface of the valve main body 206A, and the tapered portion 206D is inclined toward the shaft portion 206B toward the outside in the radial direction of the valve main body 206A. Thus, the thickness of the outer peripheral portion of the valve body 206A is set to be smaller than the thickness of the other portions.

  In the first check valve 206, the shaft portion 206B is inserted into the insertion hole 202A of the inflow-side cap 202 from above the pump. Specifically, the swelling portion 206C is inserted into the insertion hole 202A while being elastically deformed so as to be reduced in diameter inward in the radial direction, and is expanded and arranged below the top wall of the inflow-side cap 202. I have. This suppresses the shaft portion 206B from coming out of the insertion hole 202A of the inflow-side cap 202. In this state, the valve body 206A is disposed above the inflow hole 202B of the inflow side cap 202. Accordingly, when the constant displacement pump 200 is not operated, the inflow hole 202B of the inflow side cap 202 is closed by the valve body 206A. In addition, when the inflow side cap 202 is operated, the outer periphery of the valve body 206A is elastically deformed toward the pump chamber 106 due to a negative pressure in the pump chamber 106, and the inflow hole 202B of the inflow side cap 202 is opened. It has become.

  In the second check valve 208, the shaft portion 208 </ b> B is inserted into the insertion hole 204 </ b> A of the outflow-side cap 204 from the upper side of the pump, and the bulging portion 208 </ b> C is disposed below the bottom wall of the outflow-side cap 204. In this state, the valve body 208A is disposed above the outflow hole 204B of the outflow side cap 204. Accordingly, when the constant displacement pump 200 is not operated, the outflow hole 204B of the outflow side cap 204 is closed by the valve body 208A. Further, when the constant volume pump 200 is operated, the cleaning liquid in the pump chamber 106 is compressed, so that the pressure of the cleaning liquid causes the outer peripheral portion of the valve body 208A to be elastically deformed to the opposite side to the pump chamber 106 and flow out. The outflow hole 204B of the side cap 204 is opened.

  Further, as shown in FIG. 13, in the present modification, the central portion of the partition wall 88 of the cylinder 82 protrudes toward the piston accommodating portion 84, and the protruding portion is a projection 88C.

  Further, in the pump inlet 130, an inlet mounting portion 130B constituting the base end of the pump inlet 130 is formed in a substantially bottomed cylindrical shape opened to the upper side of the pump. Specifically, a substantially annular rib 130D protruding upward from the pump is formed integrally with the inlet mounting portion 130B, and the rib 130D is fitted into the distal end portion of the inflow tubular portion 84B. Further, the pump inlet 130 is projected downward from the inlet mounting portion 130B and is bent toward the solenoid housing portion 86.

  In the pump outlet 132, an outlet mounting portion 132B constituting a base end of the pump outlet 132 is formed in a substantially bottomed cylindrical shape opened to the lower side of the pump. Specifically, a substantially annular rib 132D protruding downward from the pump is formed integrally with the outlet mounting portion 132B, and the rib 132D is fitted into the distal end of the outflow tube portion 84E. The pump outlet 132 projects upward from the outlet mounting portion 132B and is bent to the opposite side of the solenoid housing 86.

  When the solenoid 114 of the constant displacement pump 200 is turned on under the control of the control unit 20, the plunger 114B moves to one axial side of the cylinder 82 against the urging force of the piston urging spring 112. Therefore, the piston 104 is pushed to one side in the axial direction of the cylinder 82 by the plunger 114B, moves to the forward movement side, and moves to the stroke end position. At this time, the inside of the pump chamber 106 becomes a negative pressure, the outer peripheral portion of the valve body 206A of the first check valve 206 is elastically deformed toward the pump chamber 106, and the inflow hole 202B of the inflow side cap 202 is opened. Become. As a result, the cleaning liquid in the inflow path 130A of the pump inlet 130 is sucked into the pump chamber 106, and the pump chamber 106 is filled with the cleaning liquid. At this time, the closed state of the outflow hole 204B of the outflow side cap 204 by the valve body 208A of the second check valve 208 is maintained.

  On the other hand, when the piston 104 reaches the stroke end position and the solenoid 114 is turned off, the plunger 114B is moved to the reversing side by the urging force of the piston urging spring 112 and is located at the initial position. At this time, the cleaning liquid in the pump chamber 106 is compressed, and the pressure of the cleaning liquid deforms the outer periphery of the valve body 208A to the opposite side to the pump chamber 106, so that the outlet hole 204B of the outlet cap 204 is opened. Become. Therefore, the cleaning liquid in the pump chamber 106 is discharged at a high pressure from the outflow passage 132A of the pump outlet 132. Thus, a constant volume of the cleaning liquid is pumped from the constant volume pump 80 to the cleaning liquid inlet 164B of the optical sensor cleaning nozzle 150 via the third hose H3. At this time, the pressure of the cleaning liquid acts on the first check valve 206, but the valve body 206A of the first check valve 206 is pressed toward the inflow side cap 202, so that the valve body 206A flows in. The hole 202B is closed. As described above, even in the constant-volume pump 200 of the modified example, a constant-volume cleaning liquid can be supplied to the optical sensor cleaning nozzle 150. Therefore, also in the present modification, the same operation and effect as in the present embodiment can be obtained.

  In the on-vehicle optical sensor cleaning device 10 of the present embodiment, the constant volume pump 80 and the optical sensor cleaning nozzle 150 are configured as separate devices. Alternatively, the optical sensor cleaning nozzle may be a vehicle-mounted optical sensor cleaning nozzle 210 in which the constant volume pump 80 and the optical sensor cleaning nozzle 150 are integrated. Hereinafter, an example of the in-vehicle optical sensor cleaning nozzle 210 will be described with reference to FIG.

  The on-vehicle optical sensor cleaning nozzle 210 shown in FIG. 14 includes a constant volume pump unit 212 configured similarly to the constant volume pump 80 and an optical sensor cleaning nozzle unit 214 configured similar to the optical sensor cleaning nozzle 150. It is comprised including. That is, the constant displacement pump section 212 includes the cylinder 82, the first cap 100, the second cap 102, the piston 104, the moving mechanism 110, the pump inlet 130, the pump outlet 132, and the first check valve 134. And a second check valve 142. The optical sensor cleaning nozzle 214 includes a cylinder housing 152, a proximal housing 160, a piston unit 170, and a return spring 178. In the optical sensor cleaning nozzle section 214, a portion corresponding to the cleaning liquid inlet 164B of the optical sensor cleaning nozzle 150 is a pump outlet 132, and the cleaning liquid discharged from the pump outlet 132 is supplied to the optical sensor cleaning nozzle section 214. It is configured to be directly pressure-fed. Accordingly, in the on-vehicle optical sensor cleaning nozzle 210, since the third hose H3 of the present embodiment is omitted, air enters the cleaning liquid supplied from the constant volume pump section 212 to the optical sensor cleaning nozzle section 214. Can be effectively suppressed.

  Further, in this embodiment, the on-vehicle optical sensor cleaning device 10 includes the gas-liquid separation device 30, but the on-vehicle optical sensor cleaning device 10 may omit the gas-liquid separation device 30.

  Further, in the present embodiment, a projection 88C is formed on the partition wall 88 of the cylinder 82, and the projection 88C is configured to contact the bottom wall 104A of the piston 104. Alternatively, a configuration may be adopted in which a projection 88C is formed on the bottom wall 104A of the piston 104, and the projection 88C is brought into contact with the partition wall 88 of the cylinder 82.

  Further, in the present embodiment, the projection 88C is formed in a columnar shape with a small height, but the shape of the projection 88C is not limited to this. For example, a dimple-shaped depression may be formed on the surface of the partition wall 88 on the piston housing portion 84 side, and a portion where the depression is not formed may be used as the projection 88C. Further, the projection 88C may be formed in a substantially spherical shape.

DESCRIPTION OF SYMBOLS 10 ... In-vehicle optical sensor cleaning device, 12 ... Washer tank, 14 ... Washer pump, 16 ... In-vehicle camera (in-vehicle optical sensor), 30 ... Gas-liquid separation device, 80 ... Constant volume pump, 82 ... Cylinder, 84 ... Piston housing part (Accommodating portion), 88: Partition wall (bottom wall of accommodating portion), 88C: Projection, 104: Piston, 104A: Bottom wall (tip of piston), 106: Pump chamber, 110: Moving mechanism, 130: Pump Inlet (inlet), 132: Pump outlet (outlet), 134: First check valve, 142: Second check valve, 150: Optical sensor cleaning nozzle, 172B: Injection port, 210: In-vehicle optical sensor cleaning nozzle, 212 … Constant displacement pump

Claims (7)

An optical sensor cleaning nozzle having an injection port for injecting the cleaning liquid in the washer tank pumped by the washer pump to the on-vehicle optical sensor,
A constant volume pump that is provided between the washer pump and the injection port and supplies a constant volume of the cleaning liquid to the injection port by operating.
Equipped with a,
A gas-liquid separator is provided between the washer pump and the optical sensor cleaning nozzle, and the constant volume pump is provided between the gas-liquid separator and the optical sensor cleaning nozzle,
The gas-liquid separation device is a vehicle-mounted optical sensor cleaning device that separates a cleaning solution pumped from the washer pump from a gas contained in the cleaning solution and causes the separated cleaning solution to flow to the constant volume pump . An optical sensor cleaning nozzle having an injection port for injecting the cleaning liquid in the washer tank pumped by the washer pump to the on-vehicle optical sensor,
A constant volume pump that is provided between the washer pump and the injection port and supplies a constant volume of the cleaning liquid to the injection port by operating.
With
The constant displacement pump,
A cylinder having a housing having a cylindrical shape with a bottom,
A piston disposed inside the housing portion, and having a distal end portion facing the bottom wall of the housing portion in the axial direction of the housing portion;
By operating, a moving mechanism that reciprocates the piston in the axial direction of the storage unit,
And including
An on- vehicle optical sensor cleaning apparatus , wherein a pump chamber is provided between a bottom wall of the housing portion and a tip portion of the piston inside the housing portion . The constant displacement pump,
An inlet provided in the housing portion, configured to be capable of flowing a cleaning liquid from the washer pump into the pump chamber;
A first portion provided in the housing portion for allowing a flow of the cleaning liquid from the inlet to the pump chamber when the piston moves forward, and suppressing a flow of the cleaning liquid from the pump chamber to the inlet when the piston moves backward; A check valve;
The on- vehicle optical sensor cleaning device according to claim 2, comprising: The constant displacement pump,
An outlet provided in the housing portion, configured to be capable of flowing out the cleaning liquid in the pump chamber to the optical sensor cleaning nozzle side,
The pump chamber is provided in the housing portion and makes communication between the outlet and the pump chamber impossible when the piston moves forward, and establishes communication between the outlet and the pump chamber when the piston moves backward. A second check valve allowing the flow of the cleaning liquid from the outlet to the outlet;
The on- vehicle optical sensor cleaning device according to claim 2 or 3 , further comprising: In the inoperative condition of the moving mechanism, vehicle optical sensor cleaning apparatus according to any one of the piston tip the housing section bottom in contact with the wall Tei Ru claims 2 4. The on-vehicle optical sensor cleaning device according to claim 5 , wherein a projection protruding toward the pump chamber is provided on at least one of a tip portion of the piston and a bottom wall of the housing portion . The in-vehicle optical sensor cleaning device according to any one of claims 1 to 6, wherein the constant displacement pump is disposed at a position closer to the optical sensor cleaning nozzle than the washer pump .

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