CN219391626U - Stretching mechanism of universal testing machine - Google Patents

Abstract

The utility model relates to a stretching mechanism of a universal testing machine, which comprises a base, wherein at least two upright posts are arranged at the peripheral edges of the base, an upper cross beam which is also used as an upper base body is arranged at the upper part of each upright post, a lower cross beam is fixed between the upper cross beam 4 and the base, a driving mechanism for driving the upper cross beam to displace is arranged in the base, through holes are respectively arranged at the central positions of the upper cross beam 4 and the lower cross beam, two ends of a steel bar test piece respectively penetrate through the through holes of the upper cross beam and the lower cross beam and are respectively anchored through an anchor, by adopting the structure, the effects that clamping and positioning are free from sliding, the tension error is small, and the characteristic tension of the steel bar displayed by the universal testing machine is equal to the real characteristic tension of the steel bar can be realized.

Description

Stretching mechanism of universal testing machine

Technical Field

The utility model relates to a stretching mechanism of a universal testing machine.

Background

The steel bar stretching clamp is an auxiliary device for testing the characteristic tension value and the characteristic elongation value which can be born by the steel bar by a universal machine. The existing stretching clamp has complex structure and complicated operation; some of the steel bar tension measuring devices are simple in structure, but the characteristic tension value of the steel bar displayed by the universal machine is higher than the true characteristic tension value of the steel bar by 20% at most due to the structure of the clamp and the contact mode of the clamp and the cross beam of the universal machine. The additional force value generated between the characteristic tension value of the steel bar displayed by the universal machine and the real characteristic tension value of the steel bar is not a fixed value, for example, a plurality of steel bar tensile test pieces with consistent length are cut out from the same straight steel bar according to the specification, the tensile test is carried out by adopting universal machines of different manufacturers or different models, or the tensile test is carried out by adopting the same universal testing machine under the condition that the maintenance degrees of the clamps are different in different time (a plurality of weeks apart), the characteristic tension value of the steel bar displayed by the universal machine is obviously different, the limit difference value is far more than the universal machine verification error specification (not more than +/-1 percent) specified by the state, and the data stability is poor. In addition, in the using stage of the universal testing machine, the internal structure of the stretching clamp is easy to wear and damage, the service life is short, the maintenance difficulty is high, and the cost is high.

Disclosure of Invention

The utility model solves the technical problem of providing the stretching clamp of the universal testing machine, which has the advantages of no slip in clamping and positioning and small stretching error and can realize that the characteristic tension of the steel bar displayed by the universal testing machine is equal to the true characteristic tension of the steel bar.

The technical scheme of the utility model is that the stretching clamp of the universal testing machine comprises a base 1 and is characterized in that at least two upright posts 2 are arranged at the peripheral edges of the base 1, an upper cross beam 4 which is also used as an upper base body is arranged at the upper part of each upright post 2, a lower cross beam 3 is fixed between the upper cross beam 4 and the base 1, a driving mechanism for driving the upper cross beam 4 to move is arranged in the base 1, through holes 11 are respectively arranged at the central positions of the upper cross beam 4 and the lower cross beam 3, two ends of a steel bar test piece 5 respectively penetrate through the through holes 11 of the upper cross beam 4 and the lower cross beam 3 and respectively clamp through an anchor 8, and multi-petal clamping pieces 10 of the anchor 8 respectively clamp the steel bar test piece 5.

The technical scheme of the utility model can also be that the driving mechanism comprises a screw rod 7 which is arranged on the base 1 and connected with an upper cross beam, and a nut of the upper cross beam 4 is sleeved on the screw rod 7 and moves along the upright post 2 under the action of a driving motor.

The technical scheme of the utility model can also be that the driving mechanism comprises a hydraulic pump arranged in the base 1, and the hydraulic pump drives the upper beam 4 to move along the upright post 2 through hydraulic pressure.

The technical scheme of the utility model can also be that a hollow cavity 9 with a trapezoid cross section is arranged at the central position of the anchor device 8, a multi-petal clamping piece 10 with a central through hole is arranged in the hollow cavity 9, and the external shape of the multi-petal clamping piece 10 is matched with the shape of the hollow cavity 9.

The technical scheme of the utility model can also be that the diameter of the through hole 11 serving as a sedimentation hole is smaller than that of the upper part of the sedimentation hole, and is about the diameter of the lower part of the sedimentation hole, a hollow cavity 9 with a trapezoid cross section is arranged at the central position of the anchor 8, a multi-petal clamping piece 10 with a central through hole is arranged in the hollow cavity 9, and the outer shape of the multi-petal clamping piece 10 is matched with the shape of the hollow cavity 9.

The utility model has the beneficial effects that at least two upright posts 2 are arranged at the peripheral edge of the base 1, an upper cross beam 4 which is also used as an upper base body is arranged at the upper part of the upright posts 2, a lower cross beam 3 is fixed between the upper cross beam 4 and the base 1, a driving mechanism for driving the upper cross beam 4 to displace is arranged in the base 1, through holes 11 are respectively arranged at the central positions of the upper cross beam 4 and the lower cross beam 3, two ends of a steel bar test piece 5 respectively pass through the through holes 11 of the upper cross beam 4 and the lower cross beam 3 and respectively clamp through an anchor 8, and multi-petal clamping pieces 10 of the anchor 8 respectively clamp the steel bar test piece 5; when the device works, a steel bar test piece with a certain length respectively passes through the through holes 11 of the upper beam 4 and the lower beam 3, then the anchorage device 8 is sleeved on the steel bar test piece, then the multi-petal clamping piece 10 is used for positioning the test length of the steel bar test piece 5, the driving system is started to drive the upper beam 4 to displace, meanwhile, the steel bar test piece is stretched and the stretching tension is transmitted to the storage through the sensor, and can be displayed in the display, as the lower part of the central position of the anchorage device 8 is concentrically provided with the hollow cavity with the trapezoid cross section, the outer edge of the hollow cavity of the anchorage device 8 is tightly contacted with the outer wall of the multi-petal clamping piece 10 while the steel bar test piece is clamped by the multi-petal clamping piece 10, the multi-petal clamping piece 10 for clamping the steel bar test piece is free from displacement, the friction force of the upper beam acting on the upright post 2 is very small, the range of verification error (+ -1%) of a specified universal machine is ignored, the clamping positioning is free, the tension error is small, and the effect that the characteristic tension of the steel bar displayed by the universal machine is equal to the real characteristic tension is realized.

Drawings

FIG. 1 is a schematic view of the structure of the present utility model

FIG. 2 is a schematic diagram of the embodiment of FIG. 1

FIG. 3 is a schematic view of another structure of FIG. 1

In fig. 1-3: 1. the device comprises a base, 2, upright posts, 3, a lower beam, 4, an upper beam, 5, a steel bar test piece, 7, a screw rod, 8, a stretching clamp, 9, a hollow cavity, 10, a multi-petal clamping piece, 11 and a through hole.

Description of the embodiments

The utility model relates to a stretching clamp of a universal testing machine, which comprises a base 1, wherein at least two upright posts 2 are arranged at the peripheral edges of the base 1, an upper cross beam 4 which is also used as an upper base body is arranged at the upper part of the upright posts 2, a lower cross beam 3 is fixed between the upper cross beam 4 and the base 1, a driving mechanism for driving the upper cross beam 4 to move is arranged in the base 1, the driving mechanism can be arranged on the base 1 and is connected with the upper cross beam to form a screw rod 7, and nuts of the upper cross beam 4 are sleeved on the screw rod 7 and move along the upright posts 2 under the action of a driving motor; the driving mechanism can also be a hydraulic pump arranged in the base 1, and the hydraulic pump drives the upper beam 4 to move along the upright post 2 through hydraulic pressure; the center positions of the upper beam 4 and the lower beam 3 are respectively provided with a through hole 11, two ends of a steel bar test piece 5 respectively pass through the through holes 11 of the upper beam 4 and the lower beam 3 and are respectively clamped by an anchor 8, and a multi-petal clamping piece 10 of the anchor 8 respectively clamps the steel bar test piece 5; the central position of the anchor device 8 is provided with a hollow cavity 9 with a trapezoid cross section, a multi-petal clamping piece 10 with a central through hole is arranged in the hollow cavity 9, and the external shape of the multi-petal clamping piece 10 is matched with the shape of the hollow cavity 9; in addition, the through hole 11 is a settling hole, the diameter of the anchor device 8 is smaller than that of the upper part of the settling hole, and is about the diameter of the lower part of the settling hole, a hollow cavity 9 with a trapezoid cross section is arranged at the central position of the anchor device 8, a multi-petal clamping piece 10 with a central through hole is arranged in the hollow cavity 9, and the external shape of the multi-petal clamping piece 10 is matched with the shape of the hollow cavity 9; when the device works, a steel bar test piece with a certain length respectively passes through the through holes 11 of the upper beam 4 and the lower beam 3, then an anchor device 8 is sleeved on the steel bar test piece, and then the multi-piece clamping piece 10 is used for positioning the test length of the steel bar test piece 5, namely, two ends of the steel bar test piece 5 respectively pass through the through holes 11 of the upper beam 4 and the lower beam 3 and are respectively anchored through the anchor device 8; the driving system is started to drive the upper beam 4 to displace, meanwhile, the steel bar test piece is stretched and the stretching tension is transmitted to the storage through the sensor, and can be displayed in the display, as the lower part of the central position of the anchorage device 8 is concentrically provided with the hollow cavity with the trapezoid cross section, the outer edge of the hollow cavity of the anchorage device 8 is tightly contacted with the outer wall of the multi-petal clamping piece 10 when the steel bar test piece is clamped through the multi-petal clamping piece 10, the multi-petal clamping piece 10 for clamping the steel bar test piece has no displacement, the friction force of the upper beam acting on the upright post 2 is very small and can be ignored, the range of the verification error (+ -1%) of the specified universal machine is far smaller, the clamping positioning non-slip is realized, the tension error is small, and the effect that the characteristic tension of the steel bar displayed by the universal machine is equal to the real characteristic tension of the steel bar can be realized.

Claims (2)

1. The stretching mechanism of the universal testing machine comprises a base (1), and is characterized in that at least two upright posts (2) are arranged at the peripheral edges of the base (1), an upper cross beam (4) which is also used as an upper base body is arranged at the upper part of the upright posts (2), a lower cross beam (3) is fixed between the upper cross beam (4) and the base (1), a driving mechanism for driving the upper cross beam (4) to displace is arranged in the base (1), through holes (11) are respectively arranged at the central positions of the upper cross beam (4) and the lower cross beam (3), two ends of a steel bar test piece (5) respectively penetrate through the through holes (11) of the upper cross beam (4) and the lower cross beam (3) and are respectively anchored through an anchor (8), the driving mechanism comprises a screw rod (7) which is arranged on the base (1) and is connected with the upper cross beam, nuts of the upper cross beam (4) are sleeved on the screw rod (7) and displace along the upright posts (2) under the action of the driving motor, the driving mechanism comprises a hydraulic pump (9) which is arranged in the base (1), a hollow cavity (9) is arranged in the hollow cavity (9) and is provided with a hollow cavity (9), the external shape of the multi-petal clamping piece (10) is matched with the shape of the hollow cavity (9).

2. The stretching mechanism of a universal testing machine according to claim 1, wherein the through hole (11) of the upper beam (4) is a sedimentation hole, the external diameter of the anchor (8) is smaller than the diameter of the upper portion of the sedimentation hole and larger than the diameter of the lower portion of the sedimentation hole, the through hole (11) of the lower beam (3) is a sedimentation hole, and the external diameter of the anchor (8) is larger than the diameter of the upper portion of the sedimentation hole and smaller than the diameter of the lower portion of the sedimentation hole.