An inflating device includes a main body, an outer cylinder, an inner cylinder, a handle, an inflating tube and a switching structure. The outer cylinder is disposed within the main body and an upper portion of the outer cylinder defines a cavity which has a bottom surface defining a sliding passage. The inner cylinder is disposed within the outer cylinder. The switching structure includes a slide unit and a press cover. The slide unit is disposed slidably in left and right directions within a sliding passage. The press cover is mounted on the upper portion of the outer cylinder so as to cover the cavity and the slide unit. The inflating device can be conveniently switched between a small pump unit and a large pump unit by the switching structure.

A metering mechanism including a metering element that is translatably mounted in a jacket, the jacket being mounted in an adjusting sleeve that can cooperate with the jacket by way of a screwing movement, the screwing/unscrewing movement causing a translatory movement of the metering element; at one end, the metering element is provided with a check valve, and at the other end, same accommodates a plunger, the reciprocating translatory movement of which creates suction at the end of the element provided with the valve, followed by expulsion into a volume surrounding the other end of the metering element via a passage formed in at least one first sealing device and in a second sealing device. A proportioning pump including a metering mechanism of the type as well as to a method for using a pump of the type in at least two metering ranges.

A metering mechanism including a metering element that is translatably mounted in a jacket, the jacket being mounted in an adjusting sleeve that can cooperate with the jacket by way of a screwing movement, the screwing/unscrewing movement causing a translatory movement of the metering element; at one end, the metering element is provided with a check valve, and at the other end, same accommodates a plunger, the reciprocating translatory movement of which creates suction at the end of the element provided with the valve, followed by expulsion into a volume surrounding the other end of the metering element via a passage formed in at least one first sealing device and in a second sealing device. A proportioning pump including a metering mechanism of the type as well as to a method for using a pump of the type in at least two metering ranges.

The inflating device has a body, a large cylinder, a small cylinder, a handle, a switching mechanism, and a switching device. The large cylinder is mounted moveably in the body and has an upper input gap, an inner bottom base, and a bottom base. The upper input gap is defined between an outer surface of a bottom end of the large cylinder and an inner surface of a first chamber of the body. The bottom base is connected with the large cylinder, is located below the inner bottom base, and has a first annular holding recess and a first O-ring. The small cylinder is mounted moveably in a second chamber of the large cylinder and has a piston base. The handle is mounted on the top end of the small cylinder. The switching mechanism is mounted on the top end of the large cylinder.

The inflating device has a body, a large cylinder, a small cylinder, a handle, a switching mechanism, and a switching device. The large cylinder is mounted moveably in the body and has an upper input gap, an inner bottom base, and a bottom base. The upper input gap is defined between an outer surface of a bottom end of the large cylinder and an inner surface of a first chamber of the body. The bottom base is connected with the large cylinder, is located below the inner bottom base, and has a first annular holding recess and a first O-ring. The small cylinder is mounted moveably in a second chamber of the large cylinder and has a piston base. The handle is mounted on the top end of the small cylinder. The switching mechanism is mounted on the top end of the large cylinder.

An inflating device includes a main body, an outer cylinder, an inner cylinder, a handle, an inflating tube and a switching structure. The outer cylinder is disposed within the main body and an upper portion of the outer cylinder defines a cavity which has a bottom surface defining a sliding passage. The inner cylinder is disposed within the outer cylinder. The switching structure includes a slide unit and a press cover. The slide unit is disposed slidably in left and right directions within a sliding passage. The press cover is mounted on the upper portion of the outer cylinder so as to cover the cavity and the slide unit. The inflating device can be conveniently switched between a small pump unit and a large pump unit by the switching structure.

A reciprocating low-speed heavy-load hydraulic pump with a variable action area comprises a plurality of hydraulic cylinder units (3) and moving members (1, 2). Two ends of the hydraulic cylinder units (3) are separately connected with the moving members (1, 2) via mechanical structures. The moving members (1, 2) move relative to each other. The hydraulic cylinder unit (3) consists of a hydraulic cylinder (4), a reversing valve (5) and a one-way valve (6). The hydraulic cylinder (4), the reversing valve (5) and the one-way valve (6) are connected with each other via hydraulic pipelines. Based on different magnitudes of driving force, the hydraulic pump can proactively configure and form different combinations of hydraulic cylinder units, and further adjust the size of an equivalent action area. Therefore, even if the magnitude of the driving force changes, it can be ensured that the hydraulic pump consisting of hydraulic cylinder units outputs oil liquid with a relatively stable pressure for use by a subsequently connected system. The reciprocating low-speed heavy-load hydraulic pump with a variable action area is advantageous in high conversion efficiency, a simple system structure and good working stability.

A reciprocating low-speed heavy-load hydraulic pump with a variable action area comprises a plurality of hydraulic cylinder units (3) and moving members (1, 2). Two ends of the hydraulic cylinder units (3) are separately connected with the moving members (1, 2) via mechanical structures. The moving members (1, 2) move relative to each other. The hydraulic cylinder unit (3) consists of a hydraulic cylinder (4), a reversing valve (5) and a one-way valve (6). The hydraulic cylinder (4), the reversing valve (5) and the one-way valve (6) are connected with each other via hydraulic pipelines. Based on different magnitudes of driving force, the hydraulic pump can proactively configure and form different combinations of hydraulic cylinder units, and further adjust the size of an equivalent action area. Therefore, even if the magnitude of the driving force changes, it can be ensured that the hydraulic pump consisting of hydraulic cylinder units outputs oil liquid with a relatively stable pressure for use by a subsequently connected system. The reciprocating low-speed heavy-load hydraulic pump with a variable action area is advantageous in high conversion efficiency, a simple system structure and good working stability.

A piston pump for a traction-controlled hydraulic vehicle braking system includes a pump piston and an annular piston that is arranged as a second piston in a resiliently loaded manner on the pump piston. As the delivery pressure increases, a resilient element is compressed and a stroke of the second piston is shortened so as to reduce a delivery quantity. This configuration enables a higher delivery pressure to be achieved for a given driving force. With low delivery pressure, the pump piston and the second piston deliver together so as to achieve a rapid build-up of pressure.

A piston pump for a traction-controlled hydraulic vehicle braking system includes a pump piston and an annular piston that is arranged as a second piston in a resiliently loaded manner on the pump piston. As the delivery pressure increases, a resilient element is compressed and a stroke of the second piston is shortened so as to reduce a delivery quantity. This configuration enables a higher delivery pressure to be achieved for a given driving force. With low delivery pressure, the pump piston and the second piston deliver together so as to achieve a rapid build-up of pressure.