Pressure detection device

Claims

1. A pressure detection device to be attached to a tire valve having a valve stem housing a valve core, The pressure detection device is A housing fastened to one end of the valve stem, A pressure sensor for detecting the pressure inside the housing, A sealing member that seals the space between the valve stem and the housing, The valve core is provided with a pressing part that opens the valve core by pressing the shaft end of the valve core, The aforementioned enclosure is An outer wall provided to cover the outer surface of the valve stem, The wall portion that contacts one end of the valve stem, It comprises a cylindrical inner wall that protrudes from the wall portion toward the interior of the valve stem, The sealing member is provided so as to be located between the outer circumferential surface of the inner wall and the inner circumferential surface of the valve stem. The outer wall has an outer wall end having an opening for receiving the valve stem, The pressing portion has a contact surface that contacts the shaft end, In the state before fastening the housing to the valve stem, where one end of the valve stem and the housing are aligned in the axial direction of the valve stem, the distance from the sealing member to the one end of the valve stem is shorter than the distance from the contact surface to the shaft end. A pressure detection device in which the distance from the outer wall end to the sealing member is shorter than the distance from the outer wall end to the contact surface.

2. A pressure detection device to be assembled to a valve having a valve stem housing a valve core, The pressure detection device is A housing fastened to one end of the valve stem, A pressure sensor for detecting the pressure inside the housing, A sealing member that seals the space between the valve stem and the housing, A pressing part that opens the valve core by pressing the shaft end of the valve core, The system includes a holder for holding the sealing member, The housing includes an outer wall provided to cover the outer circumferential surface of the valve stem, The pressing portion has a contact surface that contacts the shaft end, The pressure detection device further comprises a spring that biases the holder toward the valve stem, thereby sliding the holder and the sealing member and bringing the sealing member into close contact with the outer wall. In the state before fastening the housing to the valve stem, where one end of the valve stem and the housing are aligned in the axial direction of the valve stem, the distance from the sealing member to the one end of the valve stem is shorter than the distance from the contact surface to the shaft end. A pressure detection device in which, when the sealing member is in close contact with the outer wall, the distance from the sealing member to one end of the valve stem is shorter than the distance from the contact surface to the shaft end.