CN104655072A - Oil cylinder piston stroke measurement device employing movable rectangular rods - Google Patents

Abstract

The invention discloses an oil cylinder piston stroke measurement device employing movable rectangular rods. A measurement element of the device is an angle sensor, and a piston stroke measurement mechanism is formed by end parts of a piston rod, a swing arm of the angle sensor, the oil cylinder and a connecting rod; when the piston rod moves, the connecting rod connected with the piston rod drives the swing arm of the angle sensor to rotate, a movable signal of the piston rod is converted into an angle displacement signal of the angle sensor, and the piston moving length is calculated through measurement of a geometrical relationship of the mechanism. The oil cylinder piston stroke measurement device is simple in structure and low in manufacturing cost, does not have rigorous requirements for the work environment and can adapt to working in the wet and dusty environment.

Description

Active rectangle rod oil cylinder throw of poston measurement mechanism

Technical field

The present invention relates to hydraulic machinery, particularly a kind of oil cylinder piston stroke measuring device.

Background technology

Hydraulic jack is widely used as a kind of power, in the execution unit of many machines, the throw of poston of hydraulic jack has strict control overflow, for this reason, in industry, normal displacement transducer or the electronic ruler of adopting is as the displacement transducer of hydraulic cylinder piston stroke, the extension elongation of metering piston bar, determines the displacement of piston.This method is effective, and metering is also relatively more accurate, but the price comparison of displacement transducer and electronic ruler is high, and when many machine costs require lower, it is just not too suitable that displacement transducer and electronic ruler use.In addition, in the environment of humidity, many dirt, the part that stretches out of this kind of sensor gets rusty easily and pollutes, and causes and moves back and forth difficulty.So, need a kind of price low in production, good to rugged surroundings adaptability, measuring method is more accurately measured to hydraulic cylinder piston stroke.

Summary of the invention

The object of the invention is to for the deficiencies in the prior art, a kind of active rectangle rod oil cylinder throw of poston measurement mechanism is provided.

In order to achieve the above object, the technical solution used in the present invention is: a kind of active rectangle rod oil cylinder throw of poston measurement mechanism, and it comprises U-shaped and connects bearing, connecting rod, swing arm, rotary angle transmitter, sensor support base, oil cylinder, piston rod, U-shaped web member; Wherein, described U-shaped web member is fixedly connected with piston rod, and U-shaped connects bearing and is fixedly connected with U-shaped web member, and oil cylinder is fixedly connected with by sensor support base with rotary angle transmitter, and swing arm is fixedly connected with the rotating shaft of rotary angle transmitter; One end and the swing arm of connecting rod are hinged, and it is hinged that the other end and U-shaped are connected bearing; Connecting rod is connected the pin joint O of bearing with U-shaped ₂, rotary angle transmitter center O, cross O point perpendicular to the straight line of piston rod axis and the intersection point O of piston rod axis ₄, cross O ₂point and perpendicular to the straight line of piston rod axis and the intersection point O of piston rod axis ₃these four points form a rectangle, O ₂, O ₁with O three-point shape triangularity structure; When piston rod moves, connected connecting rod drives swing arm to rotate, and the movable signal of piston rod is converted to the angular displacement signal of rotary angle transmitter; Piston rod extension elongation is calculated by following formula:

l ₁＝l-l ₂

$l=\frac{-c\±\sqrt{c^2+4a}}{2}$

$a=l_4^2-l_3^2$

In formula, l is O ₃and O ₄distance between 2, l ₁for piston rod extension elongation, l ₂for O ₄point arrives the distance in the piston rod exit of oil cylinder, l ₃for the length of swing arm, i.e. O and O ₁distance between 2, O ₁for the pin joint of connecting rod and swing arm, l ₄for the length of connecting rod, i.e. O ₁and O ₂distance between 2, for the angle that rotary angle transmitter rotates, i.e. swing arm and O and O ₂the angle of these 2 lines.

Compared with prior art, the beneficial effect had is in the present invention:

1, adopt rotary angle transmitter as measuring element, reduce the cost of oil cylinder piston stroke measurment;

2, rod member mechanism driving is adopted, low cost of manufacture, not harsh to operating environment requirements, strong to environmental suitability that is moist, many dirt;

Accompanying drawing explanation

Fig. 1 is active rectangle rod oil cylinder throw of poston measurement mechanism sketch of the present invention;

In figure 1, U-shaped connects bearing, and 2, connecting rod, 3, swing arm, 4, rotary angle transmitter, 5, sensor support base, 6, oil cylinder, 7, piston rod, 8, U-shaped connects.

Embodiment

Below in conjunction with drawings and Examples, the present invention is further illustrated.

As shown in Figure 1, the present invention includes U-shaped and connect bearing 1, connecting rod 2, swing arm 3, rotary angle transmitter 4, sensor support base 5, oil cylinder 6, piston rod 7, U-shaped web member 8.

U-shaped web member 8 is fixedly connected with piston rod 7, U-shaped connects bearing 1 and is fixedly connected with U-shaped web member 8, sensor support base 5 is fixed together oil cylinder 6 and rotary angle transmitter 4, swing arm 3 is fixedly connected with the rotating shaft of rotary angle transmitter 4, one end and the swing arm 3 of connecting rod 2 are hinged, and the other end is connected bearing 1 with U-shaped hinged.Cross the center O of the rotary angle transmitter 4 and vertical line intersection point O of piston rod 7 axis ₄, connecting rod 2 is connected the pin joint O of bearing 1 with U-shaped ₂, cross O ₂put the vertical line intersection point O with piston rod 7 axis ₃, rotary angle transmitter 4 center O 4 form a rectangle, the pin joint O of connecting rod 2 and U-shaped web member 8 ₂, connecting rod 2 and swing arm 3 pin joint O ₁with the center O three-point shape triangularity structure of rotary angle transmitter 4.When piston rod 7 stressed displacement, be delivered in swing arm 3 by four-bar mechanism by displacement, swing arm 3 corner is measured by rotary angle transmitter 4 and is obtained, so can calculate the extension elongation of piston rod 7 by the geometric relationship measuring four-bar mechanism.

Piston rod extension elongation is calculated as follows:

l ₁＝l-l ₂

$l=\frac{-c\±\sqrt{c^2=4a}}{2}$

$a=l_4^2-l_3^2$

In formula, l-O ₃and O ₄distance between 2,

L ₁-piston rod extension elongation, i.e. O ₁and O ₃distance between 2,

L ₂-O ₄point arrives the distance in the piston rod exit of oil cylinder,

L ₃the length of-swing arm, i.e. O and O ₁distance between 2,

L ₂the length of-connecting rod, i.e. O ₁and O ₂distance between 2,

the angle that-rotary angle transmitter rotates, i.e. swing arm and O and O ₂the angle of 2 lines.

Claims (1)

1. an active rectangle rod oil cylinder throw of poston measurement mechanism, it is characterized in that, it comprises U-shaped and connects bearing (1), connecting rod (2), swing arm (3), rotary angle transmitter (4), sensor support base (5), oil cylinder (6), piston rod (7), U-shaped web member (8) etc.; Wherein, described U-shaped web member (8) is fixedly connected with piston rod (7), U-shaped connects bearing (1) and is fixedly connected with U-shaped web member (8), oil cylinder (6) is fixedly connected with by sensor support base (5) with rotary angle transmitter (4), and swing arm (3) is fixedly connected with the rotating shaft of rotary angle transmitter (4); One end and the swing arm (3) of connecting rod (2) are hinged, and the other end is connected bearing (1) with U-shaped hinged; Connecting rod (2) is connected the pin joint O of bearing (1) with U-shaped ₂, rotary angle transmitter (4) center O, cross O point perpendicular to the straight line of piston rod (7) axis and the intersection point O of piston rod (7) axis ₄, cross O ₂point and perpendicular to the straight line of piston rod (7) axis and the intersection point O of piston rod (7) axis ₃these four points form a rectangle, O ₂, O ₁with O three-point shape triangularity structure; When piston rod (7) is mobile, connected connecting rod (2) drives swing arm (3) to rotate, and the movable signal of piston rod (7) is converted to the angular displacement signal of rotary angle transmitter (4); Piston rod (7) extension elongation is calculated by following formula:

l ₁＝l-l ₂

$l=\frac{-c\±\sqrt{c^2+4a}}{2}$

$a=l_4^2-l_3^2$

In formula, l is O ₃and O ₄distance between 2, l ₁for piston rod extension elongation, l ₂for O ₄point arrives the distance in the piston rod exit of oil cylinder, l ₃for the length of swing arm, i.e. O and O ₁distance between 2, O ₁for connecting rod (2) and the pin joint of swing arm, l ₄for the length of connecting rod, i.e. O ₁and O ₂distance between 2, for the angle that rotary angle transmitter (4) rotates, i.e. swing arm and O and O ₂the angle of these 2 lines.